US20140116785A1 - Turbodrill Using a Balance Drum - Google Patents
Turbodrill Using a Balance Drum Download PDFInfo
- Publication number
- US20140116785A1 US20140116785A1 US13/843,684 US201313843684A US2014116785A1 US 20140116785 A1 US20140116785 A1 US 20140116785A1 US 201313843684 A US201313843684 A US 201313843684A US 2014116785 A1 US2014116785 A1 US 2014116785A1
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- US
- United States
- Prior art keywords
- housing
- turbodrill
- coupled
- drum assembly
- drum
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B4/00—Drives for drilling, used in the borehole
- E21B4/02—Fluid rotary type drives
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
- E21B7/04—Directional drilling
- E21B7/06—Deflecting the direction of boreholes
- E21B7/068—Deflecting the direction of boreholes drilled by a down-hole drilling motor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03B—MACHINES OR ENGINES FOR LIQUIDS
- F03B13/00—Adaptations of machines or engines for special use; Combinations of machines or engines with driving or driven apparatus; Power stations or aggregates
- F03B13/02—Adaptations for drilling wells
Definitions
- Drilling motors are commonly used to provide rotational force to a drill bit when drilling earth formations. Drilling motors used for this purpose are typically driven by drilling fluids pumped from surface equipment through a drill string. This type of motor is commonly referred to as a mud motor. In use, the drilling fluid is forced through the mud motor, which extracts energy from the flow to provide rotational force to a drill bit located below the mud motor.
- mud motors positive displacement motors (“PDM”) and turbodrills. The following disclosure focuses primarily on turbodrills; however, one of ordinary skill in the art will appreciate that balance drums disclosed herein may be similarly used in PDMs.
- FIG. 1 illustrates a cross-sectional view of a turbodrill 100 in connection with implementations of various techniques described herein.
- a housing 110 includes an uphole connection 115 to connect to the drill string.
- Turbine stages 120 are disposed within the housing 110 and may be used to rotate a shaft 130 .
- a drill bit (not shown) may be attached to the shaft 130 by a downhole connection 125 .
- stabilizers (not shown) may be disposed on the housing 110 to help keep the turbodrill centered within the wellbore.
- the turbodrill 100 may use turbine stages 120 to provide rotational force to the drill bit.
- the turbine stages 120 may consist of one or more non-moving stator vanes and a rotor assembly having rotating vanes mechanically linked to the shaft 130 .
- the turbine stages 120 may be designed such that the vanes of the stator stages direct the flow of drilling fluid into corresponding rotor blades to provide rotation to the shaft 130 , where the shaft 130 ultimately connects to and drives the drill bit.
- the high-speed drilling fluid flowing into the rotor vanes may cause the rotor and the drill bit to rotate with respect to the housing 110 .
- the turbine stages 120 may also include radial bearings provided between the shaft 130 and the housing 110 .
- the turbine stages 120 may also produce a downhole axial force, or thrust, from the drilling fluid.
- the downhole thrust may produce a higher weight on bit (WOB) than required for operation of the turbodrill 100 .
- thrust bearings 140 may be provided.
- the thrust bearings 140 may include steel roller bearings, polycrystalline diamond compact (“PDC”) surface bearings, or any other implementation known to those skilled in the art.
- a balance drum (not shown) may be used in a turbodrill to reduce axial loading on thrust bearings resulting from the downhole thrust, where the balance drum may be coupled to an uphole end of the shaft.
- the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string.
- the turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit.
- the turbodrill may further include a balance drum assembly coupled to the shaft within the housing.
- the turbodrill may include a compliant mounting disposed between the balance drum assembly and the housing, where the compliant mounting is configured to allow displacement of the balance drum assembly within the housing.
- the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string.
- the turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit.
- the turbodrill may further include a balance drum assembly coupled to the shaft within the housing.
- the turbodrill may include an elastomeric mounting disposed between the balance drum assembly and the housing, where the elastomeric mounting is configured to allow displacement of the balance drum assembly within the housing.
- the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string.
- the turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit.
- the turbodrill may further include a balance drum assembly coupled to the shaft within the housing.
- the turbodrill may include a compliant rod mechanism coupled to an uphole end of the balance drum assembly, where the compliant rod mechanism is configured to allow displacement of the balance drum assembly within the housing.
- the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string.
- the turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit.
- the turbodrill may further include a balance drum assembly coupled to the shaft within the housing.
- the turbodrill may include a rod with one or more compliant joints coupled to an uphole end of the balance drum assembly, where the rod with one or more compliant joints is configured to allow displacement of the balance drum assembly within the housing.
- the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string.
- the turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit.
- the turbodrill may further include a balance drum assembly coupled to the shaft within the housing.
- the turbodrill may include a flex shaft having an uphole end coupled to the balance drum assembly and a downhole end coupled to the rotatable shaft, where the flex shaft is configured to allow displacement of the balance drum assembly within the housing.
- the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string.
- the turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit.
- the turbodrill may further include a balance drum assembly coupled to the shaft within the housing.
- the turbodrill may include a spherical bearing assembly disposed between the balance drum assembly and the housing, where the spherical bearing assembly is configured to allow displacement of the balance drum assembly within the housing.
- FIG. 1 illustrates a cross-sectional view of a turbodrill in connection with implementations of various techniques described herein.
- FIG. 2 illustrates a cross-sectional view of a turbodrill using a balance drum assembly.
- FIGS. 3-5 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with a coil spring in accordance with implementations of various techniques described herein.
- FIG. 6 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with one or more Belleville springs and one or more rotational inhibitors in accordance with implementations of various techniques described herein.
- FIG. 7 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a rubber mounting in accordance with implementations of various techniques described herein.
- FIG. 8 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a spherical bearing assembly in accordance with implementations of various techniques described herein
- FIG. 9 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with an axial bearing cage and one or more rotational inhibitors in accordance with implementations of various techniques described herein.
- FIG. 10 illustrates a cross-sectional view of a turbodrill, using a balance drum assembly with an axial bearing cage, a spring mechanism, and one or more rotational inhibitors in accordance with implementations of various techniques described herein.
- FIG. 11 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a flex rod and a rod retainer in accordance with implementations of various techniques described herein.
- FIG. 12 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a rod, a lower universal joint, and an upper universal joint in accordance with implementations of various techniques described herein.
- FIG. 13 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with an internal flex shaft in accordance with implementations of various techniques described herein.
- FIG. 14 illustrates a cross-sectional view of the turbodrill using a balance drum assembly with an external flex shaft in accordance with implementations of various techniques described herein.
- FIG. 15 illustrates a cross-sectional view of the turbodrill using the balance drum assembly with the internal flex shaft in accordance with implementations of various techniques described herein.
- first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.
- a first object or step could be termed a second object or step, and, similarly, a second object or step could be termed a first object or step, without departing from the scope of the invention.
- the first object or step, and the second object or step are both objects or steps, respectively, but they are not to be considered the same object or step.
- the terms “up” and “down”; “upper” and “lower”; “upwardly” and downwardly”; “below” and “above”; and other similar terms indicating relative positions above or below a given point or element may be used in connection with some implementations of various technologies described herein. However, when applied to equipment and methods for use in wells that are deviated or horizontal, or when applied to equipment and methods that when arranged in a well are in a deviated or horizontal orientation, such terms may refer to a left to right, right to left, or other relationships as appropriate.
- the turbodrill may use a balance drum assembly with a compliant mounting, where the compliant mounting may be a spring mechanism, such as a coil spring.
- a balance drum assembly may be disposed within a main flow area of the turbodrill and may include a drum stator and a drum rotor.
- the drum stator may also include a cap and a sleeve, where the drum rotor may be movably disposed within the sleeve.
- the balance drum assembly may be coupled to the coil spring, which may in turn be coupled to the housing. Space may exist between the cap and an inner wall of the housing such that the coil spring may allow for a lateral displacement and an angular displacement of the balance drum assembly within the housing.
- the lateral and angular displacement via coil spring may reduce the likelihood of point loading caused by canting within the balance drum assembly, thereby avoiding wear along (e.g., in the vicinity of) a radial gap formed between an inner diameter of the sleeve and an outer diameter of the drum rotor.
- the spring mechanism may be one or more Belleville springs.
- one or more rotational inhibitors may be used to resist rotation of the drum stator within the housing in response to the flow of drilling fluid.
- the rotational inhibitors may be coupled to an inner wall of the housing and may be linked to the cap such that rotation of the drum stator is restrained.
- the turbodrill may use a balance drum assembly with a compliant mounting, which may be constructed of a solid material.
- the compliant mounting may be an elastomeric mounting.
- the balance drum assembly may be coupled to the elastomeric mounting, which may in turn be coupled to the housing.
- the elastomeric mounting may include a top portion coupled to a bottom portion. The top portion may be disposed between an inner wall of the housing and the cap. The bottom portion may be disposed between an inner shoulder of the housing and the downhole ends of the cap and the top portion.
- the top portion and the bottom portion of the elastomeric mounting may possess sufficient flexibility to allow for a lateral displacement and an angular displacement of the balance drum assembly within the housing.
- the turbodrill may use a balance drum assembly with axial bearings, such as an axial bearing cage, and one or more rotational inhibitors.
- the balance drum assembly may rest on the axial bearing cage, where the axial bearing cage may also rest on an inner shoulder of the housing.
- the one or more rotational inhibitors may be used to resist rotation of the drum stator within the housing in response to a flow of drilling fluid. Bearings of the axial bearing cage may freely rotate and allow for the lateral displacement of the balance drum assembly within the housing.
- the turbodrill may use a balance drum assembly with axial bearings, a spring mechanism, and one or more rotational inhibitors.
- the balance drum assembly may rest on the axial bearing cage, where the axial bearing cage may rest on a spring mechanism.
- the spring mechanism may rest on an inner shoulder of the housing.
- the one or more rotational inhibitors may be used to resist rotation of the drum stator within the housing in response to a flow of drilling fluid.
- Bearings of the axial bearing cage may freely rotate and allow for the lateral displacement of the balance drum assembly within the housing.
- the spring mechanism may also allow for the lateral and angular displacement of the balance drum assembly.
- the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a flex rod and rod retainer.
- the balance drum assembly may be coupled to the flex rod, where the flex rod is coupled to the rod retainer. Essentially, the balance drum assembly hangs from the rod retainer via the flex rod.
- the flex rod may allow for a lateral displacement and an angular displacement of the balance drum assembly within the housing.
- the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a rod and one or more compliant joints.
- the one or more compliant joints may include a universal joint.
- the balance drum assembly may be coupled to the rod via a lower universal joint, where the rod is coupled to the rod retainer via an upper universal joint. Essentially, the balance drum assembly hangs from the rod retainer via the rod, the lower universal joint, and the upper universal joint. Lateral and angular displacement of the balance drum assembly may be performed via the lower universal joint and the upper universal joint.
- the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a flex shaft.
- a drum rotor may be coupled to an uphole end of an internal flex shaft, such that the drum rotor may be configured to rotate in conjunction with the internal flex shaft.
- the internal flex shaft may be coupled to the drum rotor within a drum rotor annulus and within a sleeve.
- the internal flex shaft may be coupled to the main shaft, where the main shaft may extend in a down hole direction through the turbodrill.
- the internal flex shaft may allow for the lateral and angular displacement of the main shaft via binding of the internal flex shaft.
- FIG. 2 illustrates a cross-sectional view of a turbodrill 200 using a balance drum assembly 210 in connection with implementations of various techniques described herein.
- the turbodrill 200 may include a housing 202 , where the housing 202 may have an upper connection 204 for engaging with uphole members of a drill string.
- the housing 202 may further include turbine stages 240 , which may be used to rotate a shaft 230 using a flow of drilling fluid.
- Drilling fluid may include drilling mud or any other implementation known to those skilled in the art.
- the turbodrill 200 may use turbine stages 240 to provide rotational force to a drill bit (not shown).
- the turbine stages 240 may include one or more stator components, rotor components, radial bearings, or any other implementation known to those skilled in the art.
- the drill bit (not shown) may be attached to the shaft 230 by a downhole connection 250 .
- stabilizers (not shown) may be disposed on the housing 202 to help keep the turbodrill 200 centered within a wellbore.
- one or more thrust bearings 260 may be disposed proximate to the downhole end of the turbodrill 200 .
- the thrust bearings 260 may be coupled to the housing 202 and the shaft 230 .
- the thrust bearings 260 may include various components, such as steel roller bearings, polycrystalline diamond compact (“PDC”) surface bearings, or any other implementation known to those skilled in the art.
- the balance drum assembly 210 may be disposed within a main flow area 220 of the turbodrill 200 and may include a drum stator 212 and a drum rotor 214 .
- the drum stator 212 may include a cap 215 fixed to an inner wall of the housing 202 and have one or more flow ports 224 , where the one or more flow ports 224 allow drilling fluid to pass through the main flow area 220 .
- the drum stator 212 may also include a sleeve 217 descending from the cap 215 in a downhole direction 201 , where the drum rotor 214 may be movably disposed within the sleeve 217 .
- the drum rotor 214 may define a microannulus 219 within the sleeve 217 .
- the drum stator 212 may be stationary within the housing 202 .
- the drum rotor 214 may be hollow and configured to rotate within the housing 202 . Specifically, the drum rotor 214 may be configured to rotate within the sleeve 217 . The drum rotor 214 may be coupled to an uphole end of shaft 230 , such that the drum rotor 214 may be configured to rotate in conjunction with the shaft 230 .
- the shaft 230 may also be hollow such that a channel 232 may be formed with the drum rotor 214 , where the channel 232 may begin at the microannulus 219 and terminate at a vent 234 of the shaft 230 proximate to a downhole end of the shaft 230 .
- the vent 234 may open to the main flow area 220 at a location between the turbine stages 240 and the thrust bearings 260 . In another implementation, the vent 234 may open to the main flow area 220 at a location downhole from the thrust bearings 260 .
- the turbodrill 200 may receive drilling fluid 270 from an uphole member of the drill string, where the drilling fluid 270 may pass downhole through the one or more flow ports 224 . Most of the drilling fluid 270 may pass through the turbine stages 240 , whereby the drilling fluid 270 may lose fluid pressure as it reaches a portion of the main flow area 220 proximate to the vent 234 . A small amount of the drilling fluid 270 may leak through a channel or microannulus 219 formed by a radial gap 280 between an inner diameter of the sleeve 217 and an outer diameter of the drum rotor 214 .
- the radial gap 280 provides a channel or microannulus 219 for the drilling fluid 270 to leak from the main flow area 220 into the channel 232 . Further, a leak flow path may be defined from main flow area 220 through the microannulus 219 , through the channel 232 and through the vent 234 . In one implementation, the radial gap 280 may have a maximum width and a minimum width.
- the radial gap 280 may also be of a width such that there is a fluid pressure differential across the microannulus 219 between the channel 232 and the main flow area 220 outside of the sleeve 217 .
- the radial gap 280 may be of a size such that the drilling fluid 270 is inhibited from exerting significant downhole thrust on an uphole end of the shaft 230 .
- the fluid pressure inside the channel 232 may be nearly equal to the fluid pressure of the portion of the main flow area 220 proximate to the vent 234 , thereby producing the fluid pressure differential across the microannulus 219 between the channel 232 and the main flow area 220 outside of the sleeve 217 .
- This fluid pressure differential may cause an uphole axial force to act on the shaft 230 , offsetting the downhole thrust, and thereby approximately balancing an axial load applied to the shaft 230 .
- the balance drum assembly 210 may reduce axial loading on the thrust bearings 260 .
- the one or more radial bearings and/or the one or more thrust bearings 260 may each have a clearance with the shaft 230 that is greater than the radial gap 280 .
- each radial bearing and each thrust bearing 260 may have a clearance with the shaft 230 of about 0.004-0.005 inches, while the radial gap 280 may be about 0.001 inches.
- the turbodrill 200 may be forced to flex, such as when it passes through high doglegs. This flexing may force the components of the balance drum assembly 210 to behave as a bearing, such as by inducing a load within the drum stator 212 and possibly canting the drum rotor 214 within the drum stator 212 . The drum rotor 214 and/or the drum stator 212 may then wear due to friction, causing the balance drum assembly 210 to lose effectiveness in maintaining the fluid pressure differential across the microannulus 219 between the channel 232 and the main flow area 220 outside of the sleeve 217 . Various implementations may be used to minimize the canting of the drum rotor 214 within the drum stator 212 .
- FIGS. 3-8 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with a compliant mounting in accordance with implementations of various techniques described herein.
- the compliant mounting may allow for some movement of the balance drum assembly.
- the turbodrill may use a balance drum assembly with a compliant mounting, where the compliant mounting may be a spring mechanism.
- the spring mechanism may be a coil spring, one or more Belleville springs, a machine spring, a wave spring, or any other spring mechanism known to those skilled in the art.
- FIG. 3 illustrates a cross-sectional view of a turbodrill 300 using a balance drum assembly 310 with a coil spring 390 in accordance with implementations of various techniques described herein.
- the turbodrill 300 may include a housing 302 , where the housing 302 may have an upper connection for engaging with uphole members of a drill string.
- the balance drum assembly 310 may be similar to the balance drum assembly 210 , where the balance drum assembly 310 may be disposed within a main flow area 320 of the turbodrill 300 and may include a drum stator 312 and a drum rotor 314 .
- the drum stator 312 may also include a cap 315 having one or more flow ports 324 , where the one or more flow ports 324 allow drilling fluid to pass through the main flow area 320 .
- the drum stator 312 may also include a sleeve 317 descending from the cap 315 in a downhole direction 301 , where the drum rotor 314 may be movably disposed within the sleeve 317 .
- the drum rotor 314 may be hollow and configured to rotate within the housing 302 . Specifically, the drum rotor 314 may be configured to rotate within the sleeve 317 .
- the drum rotor 314 may be coupled to an uphole end of a shaft (not shown), such that the drum rotor 314 may be configured to rotate in conjunction with the shaft.
- the shaft may also be hollow such that a channel 332 may be formed with the drum rotor 314 .
- a radial gap 380 similar to the radial gap 280 may be formed between an inner diameter of the sleeve 317 and an outer diameter of the drum rotor 314 . In one implementation, the radial gap 380 may be about 0.001 inches to about 0.01 inches.
- the balance drum assembly 310 may not be fixed to the housing 302 . Instead, the balance drum assembly 310 may be coupled to the coil spring 390 , where the coil spring 390 may be coupled to the housing 302 .
- a downhole end of the cap 315 may be coupled to an uphole end of the coil spring 390 .
- the cap 315 may be coupled to the coil spring 390 through bonding, clamping, bolting, or any other implementation known to those skilled in the art.
- a downhole end of the coil spring 390 may be coupled to an inner shoulder 360 of the housing 302 .
- the coil spring 390 may be coupled to the inner shoulder 360 through bonding, clamping, bolting, or any other implementation known to those skilled in the art.
- the inner shoulder 360 may include an internal nut, bolt, or screw attached to the housing 302 .
- an outer diameter of the cap 315 may be less than an internal diameter of the main flow area 320 .
- An outer diameter of the coil spring 390 may also be less than the internal diameter of the main flow area 320 .
- space may exist between the cap 315 and an inner wall of the housing 302 such that the coil spring 390 may allow for a lateral displacement and an angular displacement of the balance drum assembly 310 within the housing 302 .
- lateral displacement of the balance drum assembly 310 may occur when a central axis of the balance drum assembly 310 is misaligned from a central axis of the housing 302 by a uniform distance.
- the coil spring 390 may allow for the lateral displacement of the balance drum assembly 310 via lateral shifting of coils in the coil spring 390 .
- angular displacement of the balance drum assembly 310 may occur when the central axis of the balance drum assembly 310 is misaligned from the central axis of the housing 302 by non-uniform distances, such that the central axis of the balance drum assembly 310 forms an angle with the central axis of the housing 302 .
- the coil spring 390 may allow for the angular displacement of the balance drum assembly 310 by compressing one side of the coil spring 390 more than the other.
- the lateral and angular displacement via coil spring 390 may lessen the likelihood of point loading due to canting within the balance drum assembly 310 , thereby avoiding wear along the radial gap 380 .
- the turbodrill 300 may allow for up to about 10 millimeters in lateral displacement of the balance drum assembly 310 within the housing 302 . In another implementation, the turbodrill 300 may allow for up to about 10 degrees of angular displacement of the balance drum assembly 310 within the housing 302 .
- the cap 315 and the coil spring 390 may be designed such that they are placed further downhole along the sleeve 317 .
- FIGS. 4 and 5 illustrate cross-sectional views of the turbodrill 300 using the balance drum assembly 310 with the coil spring 390 , where the caps 315 and the coil springs 390 are placed further downhole along the sleeve 317 in comparison to FIG. 3 .
- the cap 315 may be coupled to the coil spring 390 such that torsion of the coil spring 390 resists rotation of the drum stator 312 within the housing 302 in response to a flow of the drilling fluid.
- the drum rotor 314 may rotate in conjunction with the shaft, the drum stator 312 may remain largely stationary within the housing 302 .
- the coil spring 390 may also be configured to resist a downhole thrust resulting from the flow of the drilling fluid.
- the turbodrill may use a balance drum assembly having one or more rotational inhibitors in addition to the spring mechanism.
- the spring mechanism may be a coil spring, one or more Belleville springs, a machine spring, a wave spring, or any other spring mechanism known to those skilled in the art.
- FIG. 6 illustrates a cross-sectional view of a turbodrill 600 using a balance drum assembly 610 with one or more Belleville springs 690 and one or more rotational inhibitors 695 in accordance with implementations of various techniques described herein.
- the turbodrill 600 may include a housing 602 , where the housing 602 may have an upper connection for engaging with uphole members of a drill string.
- the balance drum assembly 610 may include the same/similar components and configuration as the balance drum assembly 310 described with reference to FIG. 3 , e.g., a drum rotor 614 , a drum stator 612 having a cap 615 and a sleeve 617 .
- the balance drum assembly 610 may rest on the one or more Belleville springs 690 , which in turn rest on an inner shoulder 660 of the housing 602 .
- a downhole end of the cap 615 may rest on an uphole end of the one or more Belleville springs 690 .
- a downhole end of the one or more Belleville springs 690 may rest on the inner shoulder 660 of the housing 602 .
- the inner shoulder 660 is similar to the inner shoulder 360 .
- the one or more Belleville springs 690 may be configured to resist a downhole thrust resulting from a flow of drilling fluid.
- One or more rotational inhibitors 695 may be used to resist rotation of the drum stator 612 within the housing 602 in response to the flow of drilling fluid.
- the rotational inhibitors 695 may be coupled to an inner wall of the housing 602 and may be linked to the cap 615 such that rotation of the drum stator 612 is restrained.
- the rotational inhibitors 695 may include one or more pins or springed pins having a first end coupled to the housing 602 and a second end engaging the cap 615 , e.g., resting within a respective gap of the cap 615 .
- the turbodrill 600 may be configured such that each pin or springed pin would rest within a particular gap of the cap 615 .
- the cap 615 may rotate a minimal distance until a pin or springed pin comes into contact with an edge of its particular gap.
- the rotational inhibitors 695 may include one or more cables having a first end coupled to the housing 602 and a second end coupled to the cap 615 . Rotation of the cap 615 would be limited by a length of the one or more cables.
- the one or more cables may be made using steel or any other implementation known to those skilled in the art.
- a lateral displacement and an angular displacement of the balance drum assembly 610 within the housing 602 may be achieved similarly to the lateral displacement and the angular displacement of the balance drum assembly 310 within the housing 302 , as the rotational inhibitors 695 may be configured to offer no resistance to the lateral and angular displacement of the balance drum assembly 610 .
- the lateral and angular displacement via the one or more Belleville springs 690 may lessen the likelihood of point loading caused by canting within the balance drum assembly 610 , thereby avoiding wear along a radial gap formed between the inner diameter of the sleeve 617 and the outer diameter of the drum rotor 614 .
- lateral displacement of the balance drum assembly 610 may occur when a central axis of the balance drum assembly 610 is misaligned from a central axis of the housing 602 by a uniform distance.
- the one or more Belleville springs 690 may allow for the lateral displacement of the balance drum assembly 610 via lateral shifting of springs in the one or more Belleville springs 690 .
- angular displacement of the balance drum assembly 610 may occur when the central axis of the balance drum assembly 610 is misaligned from the central axis of the housing 602 by non-uniform distances, such that the central axis of the balance drum assembly 610 forms an angle with the central axis of the housing 602 .
- the one or more Belleville springs 690 may allow for the angular displacement of the balance drum assembly 610 by compressing one side of the one or more Belleville springs 690 more than the other.
- the turbodrill may use a balance drum assembly with a compliant mounting constructed of a solid material.
- the compliant mounting may be an elastomeric mounting, such as a rubber mounting, a mounting composed of polytetrafluoroethylene (PTFE), or any other elastomeric mounting known to those skilled in the art.
- FIG. 7 illustrates a cross-sectional view of a turbodrill 700 using a balance drum assembly 710 with an elastomeric mounting 790 in accordance with implementations of various techniques described herein.
- the elastomeric mounting 790 may be composed of rubber.
- the turbodrill 700 may include a housing 702 , where the housing 702 may have an upper connection for engaging with uphole members of a drill string.
- the balance drum assembly 710 may include the same/similar components and configurations as the balance drum assembly 310 , e.g., a drum rotor 714 and a drum stator 712 having a cap 715 and a sleeve 717 .
- the balance drum assembly 710 may be coupled to the elastomeric mounting 790 , where the elastomeric mounting 790 is coupled to the housing 702 .
- the elastomeric mounting 790 may include a top portion 791 coupled to a bottom portion 792 .
- the elastomeric mounting 790 may be oriented such that the top portion 791 is uphole relative to the bottom portion 792 .
- the top portion 791 may be disposed between an inner wall of the housing 702 and the cap 715 .
- the top portion 791 may be coupled to the housing 702 and to the cap 715 using a bonding or any other implementation known to those in the art.
- the bottom portion 792 may be disposed between an inner shoulder 760 of the housing 702 and the downhole ends of the cap 715 and the top portion 791 .
- a downhole end of the bottom portion 792 may be coupled to the inner shoulder 760
- an uphole end of the bottom portion 792 may be coupled to the downhole ends of the cap 715 and the top portion 791 .
- the bottom portion 792 may be coupled using a bonding or any other implementation known to those in the art.
- the coupling of the top portion 791 and the bottom portion 792 to the cap 715 may help resist rotation of the drum stator 712 within the housing 702 in response to a flow of drilling fluid.
- the top portion 791 may have more compliance and/or flexibility than the bottom portion 792 .
- the top portion 791 and the bottom portion 792 may constitute one piece and may consist of material having the same compliance and/or flexibility.
- the inner shoulder 760 may include an internal nut, bolt, or screw attached to the housing.
- the top portion 791 and the bottom portion 792 of the elastomeric mounting 790 may possess sufficient compliance and/or flexibility to allow for a lateral displacement and an angular displacement of the balance drum assembly 710 within the housing 702 . Similar to the coil spring 390 , the lateral and angular displacement via the elastomeric mounting 790 may lessen the likelihood of point loading caused by canting within the balance drum assembly 710 , thereby avoiding wear along the radial gap.
- lateral displacement of the balance drum assembly 710 may occur when a central axis of the balance drum assembly 710 is misaligned from a central axis of the housing 702 by a uniform distance.
- the elastomeric mounting 790 may allow for the lateral displacement of the balance drum assembly 710 via compression of the top portion 791 and/or the bottom portion 792 .
- angular displacement of the balance drum assembly 710 may occur when the central axis of the balance drum assembly 710 is misaligned from the central axis of the housing 702 by non-uniform distances, such that the central axis of the balance drum assembly 710 forms an angle with the central axis of the housing 702 .
- the elastomeric mounting 790 may allow for the angular displacement of the balance drum assembly 710 by compressing one side of the top portion 791 and/or the bottom portion 792 more than the other.
- the turbodrill may use a balance drum assembly with a compliant mounting, where the compliant mounting is a spherical bearing assembly.
- the spherical bearing assembly may be constructed of steel, or any other implementation known to those skilled in the art.
- FIG. 8 illustrates a cross-sectional view of a turbodrill 800 using a balance drum assembly 810 with a spherical bearing assembly 890 in accordance with implementations of various techniques described herein.
- the turbodrill 800 may include a housing 802 , where the housing 802 may have an upper connection for engaging with uphole members of a drill string.
- the balance drum assembly 810 may include the same/similar components and configurations as the balance drum assembly 310 , e.g., a drum rotor 814 and a drum stator 812 having a cap 815 and a sleeve 817 .
- a ring 851 and/or a snap ring 852 may be coupled to an inner wall of the housing 802 , and may be positioned uphole relative to the cap 815 such that uphole movement of the drum stator 812 may be relatively minimized within the housing 802 .
- the spherical bearing assembly 890 may include a top spherical seat 891 configured to mate to a bottom spherical seat 892 .
- the top spherical seat 891 has an uphole end which may couple with the downhole end of the cap 815 .
- the top spherical seat 891 has an outer diameter which may be smaller than an inner diameter of the housing 802 , such that a clearance 871 may be formed.
- the top spherical seat 891 may be coupled to the cap 815 using threads or any other coupling means known to those skilled in the art.
- the top spherical seat 891 and the cap 815 may constitute one piece and may be composed of the same material.
- the top spherical seat 891 may also have a portion which may be disposed between the inner wall of the housing 802 and the cap 815 .
- a downhole end of the top spherical seat 891 may be generally convex in shape and may be configured to mate with an uphole end of the bottom spherical seat 892 , where the uphole end of the bottom spherical seat 892 may be generally concave in shape.
- a downhole end of the bottom spherical seat 892 may rest on an inner shoulder 860 of the housing 802 .
- An outer diameter of the bottom spherical seat 892 may be smaller than the inner diameter of the housing 802 , such that a clearance 872 may be formed. In one implementation, the clearance 872 may range from about 0.03 inches to 0.05 inches.
- Lateral displacement of the balance drum assembly 810 may occur when a central axis of the balance drum assembly 810 is misaligned from a central axis of the housing 802 by a uniform distance.
- clearance 872 may allow for the lateral displacement of the balance drum assembly 810 via lateral movement of the spherical bearing assembly 890 .
- the bottom spherical seat 892 may be configured to move laterally along the inner shoulder 860 , thereby allowing the spherical bearing assembly 890 and the balance drum assembly 810 to also move laterally.
- the outer diameter of the bottom spherical seat 892 may be larger than the outer diameter of the top spherical seat 891 , such that lateral displacement of the top spherical seat 891 and the balance drum assembly 810 may be limited to the lateral displacement experienced by the bottom spherical seat 892 .
- Angular displacement of the balance drum assembly 810 may occur when the central axis of the balance drum assembly 810 is misaligned from the central axis of the housing 802 by non-uniform distances, such that the central axis of the balance drum assembly 810 forms an angle with the central axis of the housing 802 .
- the convex shape of the downhole end of the top spherical seat 891 and the concave shape of the uphole end of the bottom spherical seat 892 may allow for the angular displacement of the balance drum assembly 810 .
- the top spherical seat 891 and the bottom spherical seat 892 may be configured to rotate with respect to one another, thereby allowing for angular displacement of the balance drum assembly 810 .
- FIGS. 9-10 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with axial bearings in accordance with implementations of various techniques described herein.
- the turbodrill may use a balance drum assembly with axial bearings and one or more rotational inhibitors.
- the axial bearings may be configured in an axial bearing cage having ball bearings, spherical contact bearings, tungsten carbide bearings, brass bearings, PDC surface bearings, or any other axial bearings known to those skilled in the art.
- FIG. 9 illustrates a cross-sectional view of a turbodrill 900 using a balance drum assembly 910 with an axial bearing cage 985 and one or more rotational inhibitors 995 in accordance with implementations of various techniques described herein.
- the turbodrill 900 may include a housing 902 , where the housing 902 may have an upper connection for engaging with uphole members of a drill string.
- the balance drum assembly 910 may include the same/similar components and configurations as the balance drum assembly 310 described in FIG. 3 , e.g., a drum rotor 914 and a drum stator 912 having a cap 915 and a sleeve 917 .
- the balance drum assembly 910 may rest on the axial bearing cage 985 , where the axial bearing cage 985 may also rest on an inner shoulder 960 of the housing 902 .
- a downhole end of the cap 915 may rest on an uphole end of the axial bearing cage 985 .
- a downhole end of the axial bearing cage 985 may rest on the inner shoulder 960 of the housing 902 .
- the sleeve 917 may pass through an inner ring 986 of the axial bearing cage 985 , such that the inner ring 986 may be in contact with the sleeve 917 .
- one or more rotational inhibitors 995 may be used to resist rotation of the drum stator 912 within the housing 902 in response to a flow of drilling fluid.
- the rotational inhibitors 995 may be coupled to an inner wall of the housing 902 and may be linked to the cap 915 such that rotation of the drum stator 912 is restrained.
- the rotational inhibitors 995 may include one or more pins or springed pins having a first end coupled to the housing 902 and a second end engaging the cap 915 , e.g., resting within a respective gap of the cap 915 .
- the rotational inhibitors 995 may include one or more cables having a first end coupled to the housing 902 and a second end coupled to the cap 915 .
- lateral displacement of the balance drum assembly 910 may occur when a central axis of the balance drum assembly 910 is misaligned from a central axis of the housing 902 by a uniform distance.
- bearings of the axial bearing cage 985 may freely rotate and allow for the lateral displacement of the balance drum assembly 910 within the housing 902 .
- the rotational inhibitors 995 may be configured to offer no resistance to the lateral displacement of the balance drum assembly 910 .
- the arrangement of the axial bearing cage 985 and the inner shoulder 960 may prevent angular displacement of the balance drum assembly 910 within the housing 902 .
- the lateral displacement via the axial bearing cage 985 may still lessen the likelihood of point loading resulting from canting within the balance drum assembly 910 .
- the turbodrill may use a balance drum assembly with axial bearings, a spring mechanism, and one or more rotational inhibitors.
- the axial bearings may be configured in an axial bearing cage having ball bearings, tungsten carbide bearings, brass bearings, PDC surface bearings, or any other axial bearings known to those skilled in the art.
- the spring mechanism may be a coil spring, one or more Belleville springs, a machine spring, a wave spring, or any other spring mechanism known to those skilled in the art.
- FIG. 10 illustrates a cross-sectional view of a turbodrill 1000 , using a balance drum assembly 1010 with an axial bearing cage 1085 , a spring mechanism 1090 , and one or more rotational inhibitors 1095 in accordance with implementations of various techniques described herein.
- the turbodrill 1000 may include a housing 1002 , where the housing 1002 may have an upper connection for engaging with uphole members of a drill string.
- the balance drum assembly 1010 may include the same/similar components and configurations as the balance drum assembly 310 described in FIG. 3 , e.g., a drum rotor 1014 and a drum stator 1012 having a cap 1015 and a sleeve 1017 .
- the balance drum assembly 1010 may rest on the axial bearing cage 1085 , where the axial bearing cage 1085 may rest on a spring mechanism 1090 .
- the spring mechanism 1090 may rest on an inner shoulder 1060 of the housing 1002 .
- a downhole end of the cap 1015 may rest on an uphole end of the axial bearing cage 1085 .
- a downhole end of the axial bearing cage 1085 may rest on an uphole end of the spring mechanism 1090 , where a downhole end of the spring mechanism 1000 may rest on the inner shoulder 1060 of the housing 1002 .
- the sleeve 1017 may pass through an inner ring 1086 of the axial bearing cage 1085 , such that the inner ring 1086 may be in contact with the sleeve 1017 .
- one or more rotational inhibitors 1095 may be used to resist rotation of the drum stator 1012 within the housing 1002 in response to a flow of drilling fluid.
- the rotational inhibitors 1095 may be coupled to an inner wall of the housing 1002 and may be linked to the cap 1015 such that rotation of the drum stator 1012 is restrained.
- the rotational inhibitors 1095 may include one or more pins or springed pins having a first end coupled to the housing 1002 and a second end engaging the cap 1015 , e.g., resting within a respective gap of the cap 1015 .
- the rotational inhibitors 1095 may include one or more cables having a first end coupled to the housing 1002 and a second end coupled to the cap 1015 .
- lateral displacement of the balance drum assembly 1010 may occur when a central axis of the balance drum assembly 1010 is misaligned from a central axis of the housing 1002 by a uniform distance.
- bearings of the axial bearing cage 1085 may freely rotate and allow for the lateral displacement of the balance drum assembly 1010 within the housing 1002 .
- the spring mechanism 1090 may allow for the lateral displacement of the balance drum assembly 1010 via lateral shifting of springs in the spring mechanism 1090 . Similar to the rotational inhibitors 695 , the rotational inhibitors 1095 may be configured to offer little or no resistance to the lateral displacement of the balance drum assembly 1010 .
- angular displacement of the balance drum assembly 1010 may occur when the central axis of the balance drum assembly 1010 is misaligned from the central axis of the housing 1002 by non-uniform distances, such that the central axis of the balance drum assembly 1010 forms an angle with the central axis of the housing 1002 .
- the spring mechanism 1090 may allow for the angular displacement of the balance drum assembly 1010 by compressing one side of the spring mechanism 1090 more than the other.
- the lateral and angular displacement via the spring mechanism 1090 and/or the axial bearing cage 1085 may lessen the likelihood of point loading caused by canting within the balance drum assembly 1010 , thereby avoiding wear along the radial gap.
- FIGS. 11-15 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with a compliant rod mechanism in accordance with implementations of various techniques described herein.
- the compliant rod mechanism may allow for some movement of the balance drum assembly.
- the compliant rod mechanism includes a flex rod and rod retainer.
- FIG. 11 illustrates a cross-sectional view of a turbodrill 1100 using a balance drum assembly 1110 with a flex rod 1190 and a rod retainer 1191 in accordance with implementations of various techniques described herein.
- the turbodrill 1100 may include a housing 1102 , where the housing 1102 may have an upper connection for engaging with uphole members of a drill string.
- a balance drum assembly 1110 may be disposed within a main flow area 1120 of the turbodrill 1100 and may include a drum stator 1112 and a drum rotor 1114 .
- the drum rotor 1114 may be movably disposed within the drum stator 1112 .
- the drum rotor 1114 may also be hollow and configured to rotate within the housing 1102 .
- the drum rotor 1114 may be configured to rotate within the drum stator 1112 .
- the drum rotor 1114 may be coupled to an uphole end of a shaft (not shown), such that the drum rotor 1114 may be configured to rotate in conjunction with the shaft.
- the shaft may also be hollow such that a channel 1132 may be formed with the drum rotor 1114 .
- a radial gap 1180 similar to the radial gap 280 may be formed between an inner diameter of the drum stator 1112 and an outer diameter of the drum rotor 1114 .
- the balance drum assembly 1110 may not be fixed to the housing 1102 . Instead, the balance drum assembly 1110 may be coupled to the flex rod 1190 , where the flex rod 1190 is coupled to the rod retainer 1191 . Essentially, the balance drum assembly 1110 hangs from the rod retainer 1191 via the flex rod 1190 . In particular, a downhole end of the flex rod 1190 may be coupled to an uphole end of the drum stator 1112 . The flex rod 1190 may be coupled to the drum stator 1112 through bonding, clamping, bolting, welding, threading, pinning, or any other implementation known to those skilled in the art.
- an uphole end of the flex rod 1190 may be coupled to a downhole end of the rod retainer 1191 .
- the flex rod 1190 may be coupled to the rod retainer 1191 through bonding, clamping, bolting, welding, threading, or any other implementation known to those skilled in the art.
- the rod retainer 1191 may have one or more flow ports 1124 for allowing drilling fluid to pass through the main flow area 1120 .
- the downhole end of the rod retainer 1191 may be disposed on an inner shoulder 1160 of the housing 1102 .
- the inner shoulder 1160 may include an internal nut, bolt, or screw attached to the housing 1102 .
- an outer diameter of the drum stator 1112 may be less than an internal diameter of the main flow area 1120 .
- space may exist between the drum stator 1112 and an inner wall of the housing 1102 such that the flex rod 1190 may allow for a lateral displacement and an angular displacement of the balance drum assembly 1110 within the housing 1102 .
- the flex rod 1190 may be a cable attachment, a coil spring, a rod composed of titanium, flexible steel, or any other compliant material known to those skilled in the art which would allow displacement of the balance drum assembly 1110 within the housing 1102 .
- the flex rod 1190 in order to maximize compliance and/or flexibility of the flex rod 1190 , the flex rod 1190 may be designed to be as long and as thin as allowed under the design constraints for the turbodrill 1100 .
- lateral displacement of the balance drum assembly 1110 may occur when a central axis of the balance drum assembly 1110 is misaligned from a central axis of the housing 1102 by a uniform distance. Accordingly, the flex rod 1190 may allow for the lateral displacement of the balance drum assembly 1110 via bending of the flex rod 1190 .
- angular displacement of the balance drum assembly 1110 may occur when the central axis of the balance drum assembly 1110 is misaligned from the central axis of the housing 1102 by non-uniform distances, such that the central axis of the balance drum assembly 1110 forms an angle with the central axis of the housing 1102 .
- the flex rod 1190 may allow for the angular displacement of the balance drum assembly 1110 via bending of the flex rod 1190 .
- the lateral and angular displacement via the flex rod 1190 may lessen the likelihood of point loading caused by canting within the balance drum assembly 1110 , thereby avoiding wear along the radial gap 1180 .
- torsion of the flex rod 1190 may resist rotation of the drum stator 1112 within the housing 1102 in response to a flow of the drilling fluid.
- the rod retainer 1191 may be largely stationary within the housing 1102 .
- the drum stator 1112 may remain largely stationary within the housing 1102 .
- the flex rod 1190 may also be configured to handle a downhole thrust resulting from the flow of the drilling fluid.
- one or more rotational inhibitors such as those discussed with respect to FIG. 6 , may be used to restrain rotation of the drum stator 1112 .
- the compliant rod mechanism includes a rod, a rod retainer, and one or more compliant joints.
- the one or more compliant joints may include a universal joint, a constant-velocity (CV) joint, or any other compliant joint known to those skilled in the art.
- FIG. 12 illustrates a cross-sectional view of a turbodrill 1200 using a balance drum assembly 1210 with a rod 1290 , a lower universal joint 1293 , and an upper universal joint 1295 in accordance with implementations of various techniques described herein.
- the turbodrill 1200 may include a housing 1202 , where the housing 1202 may have an upper connection for engaging with uphole members of a drill string.
- the balance drum assembly 1210 may be disposed within the housing 1202 , and may include a drum rotor 1214 and a drum stator 1212 . It should be understood that the housing 1202 is similar to the housing 1002 , and the balance drum assembly 1210 is similar to the balance drum assembly 1010 . In particular, the drum rotor 1214 is similar to the drum rotor 1114 , and the drum stator 1212 is similar to the drum stator 1112 .
- the turbodrill 1200 may also include a rod retainer 1291 similar to the rod retainer 1191 .
- the balance drum assembly 1210 may be coupled to the rod 1290 via the lower universal joint 1293 , where the rod 1290 is coupled to the rod retainer 1291 via the upper universal joint 1295 . Essentially, the balance drum assembly 1210 hangs from the rod retainer 1291 via the rod 1090 , the lower universal joint 1293 , and the upper universal joint 1295 . In particular, a downhole end of the rod 1290 may be coupled to an uphole end of the drum stator 1212 via the lower universal joint 1293 .
- an uphole end of the rod 1290 may be coupled to a downhole end of the rod retainer 1291 via the upper universal joint 1295 .
- the downhole end of the rod retainer 1291 may also be disposed on an inner shoulder 1260 of the housing 1202 .
- the inner shoulder 1260 may be similar to the inner shoulder 1160 .
- the rod 1290 may be composed of any material known to those skilled in the art which would support the configuration of the balance drum assembly 1210 within the housing 1202 as described herein.
- lateral displacement of the balance drum assembly 1210 may occur when a central axis of the balance drum assembly 1210 is misaligned from a central axis of the housing 1202 by a uniform distance. Accordingly, the balance drum assembly 1210 may be laterally displaced through pivoting of both the lower universal joint 1293 and the upper universal joint 1295 .
- angular displacement of the balance drum assembly 1210 may occur when the central axis of the balance drum assembly 1210 is misaligned from the central axis of the housing 1202 by non-uniform distances, such that the central axis of the balance drum assembly 1210 forms an angle with the central axis of the housing 1202 . Accordingly, the balance drum assembly 1210 may be angularly displaced through pivoting of either the lower universal joint 1293 or the upper universal joint 1295 .
- the lateral and angular displacement via the lower universal joint 1293 and the upper universal joint 1295 may lessen the likelihood of point loading caused by canting within the balance drum assembly 1210 , thereby avoiding wear along the radial gap formed between an inner diameter of the drum stator 1212 and an outer diameter of the drum rotor 1214 .
- the rod 1290 , the lower universal joint 1293 , and the upper universal joint 1295 may be configured to resist rotation of the drum stator 1212 within the housing 1202 in response to a flow of the drilling fluid.
- the rod 1290 , the lower universal joint 1293 , and the upper universal joint 1295 may also be configured to handle a downhole thrust resulting from the flow of the drilling fluid.
- the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a flex shaft.
- FIG. 13 illustrates a cross-sectional view of a turbodrill 1300 using a balance drum assembly 1310 with an internal flex shaft 1390 in accordance with implementations of various techniques described herein.
- the turbodrill 1300 may include a housing 1302 , where the housing 1302 may have an upper connection for engaging with uphole members of a drill string.
- a balance drum assembly 1310 may be disposed within a main flow area 1320 of the turbodrill 1300 and may include a drum stator 1312 and a drum rotor 1314 .
- the drum stator 1312 may include a cap 1315 and a sleeve 1317 descending from the cap 1315 in a downhole direction 1301 .
- An uphole end of the cap 1315 may have openings for one or more flow ports 1324 , where the one or more flow ports 1324 allow drilling fluid to pass in the downhole direction 1301 through one or more channels in the sleeve 1317 and to the main flow area 1320 .
- the drum stator 1312 may be largely stationary within the housing 1302 .
- a downhole end of the sleeve 1317 may be disposed on an inner shoulder 1360 of the housing 1302 .
- the inner shoulder 1360 may include an internal nut, bolt, or screw attached to the housing 1302 .
- the drum rotor 1314 may be movably disposed within the sleeve 1317 , where the drum rotor 1314 may be hollow and configured to rotate.
- the drum rotor 1314 may be configured to rotate within the sleeve 1317 .
- a radial gap 1380 similar to the radial gap 280 , may be formed between an inner diameter of the sleeve 1317 and an outer diameter of the drum rotor 1314 .
- the drum rotor 1314 may be coupled to an uphole end of the internal flex shaft 1390 , such that the drum rotor 1314 may be configured to rotate in conjunction with the internal flex shaft 1390 .
- the uphole end of the internal flex shaft 1390 may be coupled to the drum rotor 1314 within a drum rotor annulus 1318 and within the sleeve 1317 , where the drum rotor annulus 1318 may be defined by an inner bore of the drum rotor 1314 .
- a downhole end of the internal flex shaft 1390 may be coupled to an uphole end of a main shaft 1330 , where the main shaft 1330 may extend in a downhole direction 1301 through the turbodrill 1300 and may be coupled to a drill bit (not shown).
- the internal flex shaft 1390 and the main shaft 1330 may both be hollow such that a channel 1332 may be formed with the drum rotor 1314 .
- the internal flex shaft 1390 may be configured to rotate in conjunction with the main shaft 1330 .
- the internal flex shaft 1390 may be coupled to the main shaft 1330 and to the drum rotor 1314 using threads, screws, bolts, or any other coupling mechanism known to those skilled in the art.
- space may exist within the main flow area 1320 and/or the drum rotor annulus 1318 such that the internal flex shaft 1390 may allow for a lateral displacement and an angular displacement of the main shaft 1330 within the housing 1302 .
- lateral displacement of the main shaft 1330 may occur when a central axis of the main shaft 1330 is misaligned from a central axis of the housing 1302 by a uniform distance.
- the internal flex shaft 1390 may allow for the lateral displacement of the main shaft 1330 via bending of the internal flex shaft 1390 .
- angular displacement of the main shaft 1330 may occur when the central axis of the main shaft 1330 is misaligned from the central axis of the housing 1302 by non-uniform distances, such that the central axis of the main shaft 1330 forms an angle with the central axis of the housing 1302 .
- the internal flex shaft 1390 may allow for the angular displacement of the main shaft 1330 via bending of the internal flex shaft 1390 .
- the lateral and angular displacement via the internal flex shaft 1390 may lessen the likelihood of point loading caused by canting within the balance drum assembly 1310 , thereby avoiding wear along the radial gap 1380 .
- the bending of the internal flex shaft 1390 may occur within the drum rotor annulus 1318 .
- the flex shaft may be coupled to the drum rotor 1314 further downhole along the turbodrill 1300 .
- FIG. 14 illustrates a cross-sectional view of the turbodrill 1300 using the balance drum assembly 1310 with an external flex shaft 1490 in accordance with implementations of various techniques described herein.
- an uphole end of the external flex shaft 1490 may be coupled to a downhole end of the drum rotor 1314 located outside of the sleeve 1317 .
- the flex shafts 1390 and 1490 may be composed of titanium, flexible steel, or any other compliant material known to those skilled in the art which would allow displacement of the main shaft 1330 within the housing 1302 .
- one or more vents 1334 may be placed proximate to the balance drum assembly 1310 .
- FIG. 15 illustrates a cross-sectional view of the turbodrill 1300 using the balance drum assembly 1310 with the internal flex shaft 1390 in accordance with implementations of various techniques described herein.
- the vents 1334 may be positioned along the housing 1302 , such that the vents open to an area outside of the turbodrill 1300 .
- this area is formed by an outer diameter of the housing 1302 and an inner wall of a borehole in which the turbodrill 1300 is placed. This area may have lower fluid pressure relative to a main flow area 1320 of the turbodrill 1300 .
- the vents 1334 may be connected to a channel 1333 formed within the cap 1315 of the drum stator 1312 , leading to a microannulus 1319 .
- the microannulus 1319 may be similar to the microannulus 219 , and may be defined by the drum rotor 1314 within the sleeve 1317 .
- drilling fluid may leak from the main flow area 1320 , through the radial gap 1380 , and into the microannulus 1319 .
- the drilling fluid may be prevented from exerting significant downhole thrust on an uphole end of the internal flex shaft 1390 due to the connection between the vents 1334 and the microannulus 1319 .
- connection to the lower pressure area outside of the turbodrill 1300 may mitigate downhole thrust acting on the internal flex shaft 1390 , and therefore, the balance drum assembly 1310 may reduce axial loading on any thrust bearings.
- the internal flex shaft 1390 and/or the main shaft 1330 may be composed of solid material, such that, unlike shaft 230 of FIG. 2 , the internal flex shaft 1390 and/or the main shaft 1330 may not be hollow.
- the turbodrills and their respective balance drum assemblies described above with respect to FIGS. 1-15 allow for the turbodrills to follow angular deflections of the shaft, whether from a curved design or from directional drilling.
- the lateral and angular displacement used in the turbodrills above may lessen the likelihood of point loading due to canting within the balance drum assemblies.
- the turbodrills above are also arranged and designed to handle a downhole thrust resulting from a flow of drilling fluid through the tools.
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Abstract
A turbodrill using a balance drum. The turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include a compliant mounting disposed between the balance drum assembly and the housing, where the compliant mounting is configured to allow displacement of the balance drum assembly within the housing.
Description
- This application claims benefit of U.S. provisional patent application Ser. No. 61/721,410, filed Nov. 1, 2012 and titled TURBODRILL USING A BALANCE DRUM, the entire disclosure of which are herein incorporated by reference.
- The following descriptions and examples do not constitute an admission as prior art by virtue of their inclusion within this section.
- Drilling motors are commonly used to provide rotational force to a drill bit when drilling earth formations. Drilling motors used for this purpose are typically driven by drilling fluids pumped from surface equipment through a drill string. This type of motor is commonly referred to as a mud motor. In use, the drilling fluid is forced through the mud motor, which extracts energy from the flow to provide rotational force to a drill bit located below the mud motor. There are two primary types of mud motors: positive displacement motors (“PDM”) and turbodrills. The following disclosure focuses primarily on turbodrills; however, one of ordinary skill in the art will appreciate that balance drums disclosed herein may be similarly used in PDMs.
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FIG. 1 illustrates a cross-sectional view of aturbodrill 100 in connection with implementations of various techniques described herein. Ahousing 110 includes anuphole connection 115 to connect to the drill string.Turbine stages 120 are disposed within thehousing 110 and may be used to rotate ashaft 130. At a downhole end of theturbodrill 100, a drill bit (not shown) may be attached to theshaft 130 by adownhole connection 125. In addition, stabilizers (not shown) may be disposed on thehousing 110 to help keep the turbodrill centered within the wellbore. - The
turbodrill 100 may useturbine stages 120 to provide rotational force to the drill bit. Theturbine stages 120 may consist of one or more non-moving stator vanes and a rotor assembly having rotating vanes mechanically linked to theshaft 130. Theturbine stages 120 may be designed such that the vanes of the stator stages direct the flow of drilling fluid into corresponding rotor blades to provide rotation to theshaft 130, where theshaft 130 ultimately connects to and drives the drill bit. Thus, the high-speed drilling fluid flowing into the rotor vanes may cause the rotor and the drill bit to rotate with respect to thehousing 110. Theturbine stages 120 may also include radial bearings provided between theshaft 130 and thehousing 110. - While providing rotational force to the
shaft 130, theturbine stages 120 may also produce a downhole axial force, or thrust, from the drilling fluid. The downhole thrust, however, may produce a higher weight on bit (WOB) than required for operation of theturbodrill 100. To mitigate the effects of excess thrust in theturbodrill 100,thrust bearings 140 may be provided. Thethrust bearings 140 may include steel roller bearings, polycrystalline diamond compact (“PDC”) surface bearings, or any other implementation known to those skilled in the art. - The excess downhole thrust produced from the drilling fluid may also cause damage to the hard materials of the
thrust bearings 140, thereby reducing the life of thethrust bearings 140. A balance drum (not shown) may be used in a turbodrill to reduce axial loading on thrust bearings resulting from the downhole thrust, where the balance drum may be coupled to an uphole end of the shaft. - Described herein are implementations of various technologies for a turbodrill using a balance drum. In one implementation, the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include a compliant mounting disposed between the balance drum assembly and the housing, where the compliant mounting is configured to allow displacement of the balance drum assembly within the housing.
- In another implementation, the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include an elastomeric mounting disposed between the balance drum assembly and the housing, where the elastomeric mounting is configured to allow displacement of the balance drum assembly within the housing.
- In yet another implementation, the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include a compliant rod mechanism coupled to an uphole end of the balance drum assembly, where the compliant rod mechanism is configured to allow displacement of the balance drum assembly within the housing.
- In another implementation, the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include a rod with one or more compliant joints coupled to an uphole end of the balance drum assembly, where the rod with one or more compliant joints is configured to allow displacement of the balance drum assembly within the housing.
- In another implementation, the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include a flex shaft having an uphole end coupled to the balance drum assembly and a downhole end coupled to the rotatable shaft, where the flex shaft is configured to allow displacement of the balance drum assembly within the housing.
- In yet another implementation, the turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include a spherical bearing assembly disposed between the balance drum assembly and the housing, where the spherical bearing assembly is configured to allow displacement of the balance drum assembly within the housing.
- The above referenced summary section is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description section. The summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.
- Implementations of various techniques will hereafter be described with reference to the accompanying drawings. It should be understood, however, that the accompanying drawings illustrate only the various implementations described herein and are not meant to limit the scope of various techniques described herein.
-
FIG. 1 illustrates a cross-sectional view of a turbodrill in connection with implementations of various techniques described herein. -
FIG. 2 illustrates a cross-sectional view of a turbodrill using a balance drum assembly. -
FIGS. 3-5 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with a coil spring in accordance with implementations of various techniques described herein. -
FIG. 6 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with one or more Belleville springs and one or more rotational inhibitors in accordance with implementations of various techniques described herein. -
FIG. 7 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a rubber mounting in accordance with implementations of various techniques described herein. -
FIG. 8 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a spherical bearing assembly in accordance with implementations of various techniques described herein -
FIG. 9 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with an axial bearing cage and one or more rotational inhibitors in accordance with implementations of various techniques described herein. -
FIG. 10 illustrates a cross-sectional view of a turbodrill, using a balance drum assembly with an axial bearing cage, a spring mechanism, and one or more rotational inhibitors in accordance with implementations of various techniques described herein. -
FIG. 11 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a flex rod and a rod retainer in accordance with implementations of various techniques described herein. -
FIG. 12 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with a rod, a lower universal joint, and an upper universal joint in accordance with implementations of various techniques described herein. -
FIG. 13 illustrates a cross-sectional view of a turbodrill using a balance drum assembly with an internal flex shaft in accordance with implementations of various techniques described herein. -
FIG. 14 illustrates a cross-sectional view of the turbodrill using a balance drum assembly with an external flex shaft in accordance with implementations of various techniques described herein. -
FIG. 15 illustrates a cross-sectional view of the turbodrill using the balance drum assembly with the internal flex shaft in accordance with implementations of various techniques described herein. - The discussion below is directed to certain specific implementations. It is to be understood that the discussion below is only for the purpose of enabling a person with ordinary skill in the art to make and use any subject matter defined now or later by the patent “claims” found in any issued patent herein.
- It is specifically intended that the claimed invention not be limited to the implementations and illustrations contained herein, but include modified forms of those implementations including portions of the implementations and combinations of elements of different implementations as come within the scope of the following claims. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. Nothing in this application is considered critical or essential to the claimed invention unless explicitly indicated as being “critical” or “essential.”
- It will also be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first object or step could be termed a second object or step, and, similarly, a second object or step could be termed a first object or step, without departing from the scope of the invention. The first object or step, and the second object or step, are both objects or steps, respectively, but they are not to be considered the same object or step.
- As used herein, the terms “up” and “down”; “upper” and “lower”; “upwardly” and downwardly”; “below” and “above”; and other similar terms indicating relative positions above or below a given point or element may be used in connection with some implementations of various technologies described herein. However, when applied to equipment and methods for use in wells that are deviated or horizontal, or when applied to equipment and methods that when arranged in a well are in a deviated or horizontal orientation, such terms may refer to a left to right, right to left, or other relationships as appropriate.
- The following paragraphs provide a brief summary of various technologies and techniques directed at a turbodrill using a balance drum in accordance with various implementations described herein.
- In one implementation, the turbodrill may use a balance drum assembly with a compliant mounting, where the compliant mounting may be a spring mechanism, such as a coil spring. A balance drum assembly may be disposed within a main flow area of the turbodrill and may include a drum stator and a drum rotor. The drum stator may also include a cap and a sleeve, where the drum rotor may be movably disposed within the sleeve. The balance drum assembly may be coupled to the coil spring, which may in turn be coupled to the housing. Space may exist between the cap and an inner wall of the housing such that the coil spring may allow for a lateral displacement and an angular displacement of the balance drum assembly within the housing. The lateral and angular displacement via coil spring may reduce the likelihood of point loading caused by canting within the balance drum assembly, thereby avoiding wear along (e.g., in the vicinity of) a radial gap formed between an inner diameter of the sleeve and an outer diameter of the drum rotor.
- In another implementation, the spring mechanism may be one or more Belleville springs. Further, one or more rotational inhibitors may be used to resist rotation of the drum stator within the housing in response to the flow of drilling fluid. The rotational inhibitors may be coupled to an inner wall of the housing and may be linked to the cap such that rotation of the drum stator is restrained.
- In yet another implementation, the turbodrill may use a balance drum assembly with a compliant mounting, which may be constructed of a solid material. As an example, the compliant mounting may be an elastomeric mounting. The balance drum assembly may be coupled to the elastomeric mounting, which may in turn be coupled to the housing. The elastomeric mounting may include a top portion coupled to a bottom portion. The top portion may be disposed between an inner wall of the housing and the cap. The bottom portion may be disposed between an inner shoulder of the housing and the downhole ends of the cap and the top portion. The top portion and the bottom portion of the elastomeric mounting may possess sufficient flexibility to allow for a lateral displacement and an angular displacement of the balance drum assembly within the housing.
- In still another implementation, the turbodrill may use a balance drum assembly with axial bearings, such as an axial bearing cage, and one or more rotational inhibitors. The balance drum assembly may rest on the axial bearing cage, where the axial bearing cage may also rest on an inner shoulder of the housing. The one or more rotational inhibitors may be used to resist rotation of the drum stator within the housing in response to a flow of drilling fluid. Bearings of the axial bearing cage may freely rotate and allow for the lateral displacement of the balance drum assembly within the housing.
- In still yet another implementation, the turbodrill may use a balance drum assembly with axial bearings, a spring mechanism, and one or more rotational inhibitors. The balance drum assembly may rest on the axial bearing cage, where the axial bearing cage may rest on a spring mechanism. In turn, the spring mechanism may rest on an inner shoulder of the housing. The one or more rotational inhibitors may be used to resist rotation of the drum stator within the housing in response to a flow of drilling fluid. Bearings of the axial bearing cage may freely rotate and allow for the lateral displacement of the balance drum assembly within the housing. The spring mechanism may also allow for the lateral and angular displacement of the balance drum assembly.
- In still yet another implementation, the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a flex rod and rod retainer. The balance drum assembly may be coupled to the flex rod, where the flex rod is coupled to the rod retainer. Essentially, the balance drum assembly hangs from the rod retainer via the flex rod. The flex rod may allow for a lateral displacement and an angular displacement of the balance drum assembly within the housing.
- In another implementation, the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a rod and one or more compliant joints. In such an implementation, the one or more compliant joints may include a universal joint. The balance drum assembly may be coupled to the rod via a lower universal joint, where the rod is coupled to the rod retainer via an upper universal joint. Essentially, the balance drum assembly hangs from the rod retainer via the rod, the lower universal joint, and the upper universal joint. Lateral and angular displacement of the balance drum assembly may be performed via the lower universal joint and the upper universal joint.
- In another implementation, the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a flex shaft. A drum rotor may be coupled to an uphole end of an internal flex shaft, such that the drum rotor may be configured to rotate in conjunction with the internal flex shaft. In particular, the internal flex shaft may be coupled to the drum rotor within a drum rotor annulus and within a sleeve. The internal flex shaft may be coupled to the main shaft, where the main shaft may extend in a down hole direction through the turbodrill. The internal flex shaft may allow for the lateral and angular displacement of the main shaft via binding of the internal flex shaft.
- Various implementations described above will now be described in more detail with reference to
FIGS. 2-15 . -
FIG. 2 illustrates a cross-sectional view of aturbodrill 200 using abalance drum assembly 210 in connection with implementations of various techniques described herein. In one implementation, theturbodrill 200 may include ahousing 202, where thehousing 202 may have anupper connection 204 for engaging with uphole members of a drill string. - The
housing 202 may further include turbine stages 240, which may be used to rotate ashaft 230 using a flow of drilling fluid. Drilling fluid may include drilling mud or any other implementation known to those skilled in the art. In particular, theturbodrill 200 may useturbine stages 240 to provide rotational force to a drill bit (not shown). The turbine stages 240 may include one or more stator components, rotor components, radial bearings, or any other implementation known to those skilled in the art. At a downhole end of theturbodrill 200, the drill bit (not shown) may be attached to theshaft 230 by adownhole connection 250. In addition, stabilizers (not shown) may be disposed on thehousing 202 to help keep the turbodrill 200 centered within a wellbore. - To reduce axial loading resulting from the flow of drilling fluid, one or
more thrust bearings 260 may be disposed proximate to the downhole end of theturbodrill 200. Thethrust bearings 260 may be coupled to thehousing 202 and theshaft 230. Thethrust bearings 260 may include various components, such as steel roller bearings, polycrystalline diamond compact (“PDC”) surface bearings, or any other implementation known to those skilled in the art. - The
balance drum assembly 210 may be disposed within amain flow area 220 of theturbodrill 200 and may include adrum stator 212 and adrum rotor 214. Thedrum stator 212 may include acap 215 fixed to an inner wall of thehousing 202 and have one ormore flow ports 224, where the one ormore flow ports 224 allow drilling fluid to pass through themain flow area 220. Thedrum stator 212 may also include asleeve 217 descending from thecap 215 in adownhole direction 201, where thedrum rotor 214 may be movably disposed within thesleeve 217. Thedrum rotor 214 may define amicroannulus 219 within thesleeve 217. Thedrum stator 212 may be stationary within thehousing 202. - In one implementation, the
drum rotor 214 may be hollow and configured to rotate within thehousing 202. Specifically, thedrum rotor 214 may be configured to rotate within thesleeve 217. Thedrum rotor 214 may be coupled to an uphole end ofshaft 230, such that thedrum rotor 214 may be configured to rotate in conjunction with theshaft 230. Theshaft 230 may also be hollow such that achannel 232 may be formed with thedrum rotor 214, where thechannel 232 may begin at themicroannulus 219 and terminate at avent 234 of theshaft 230 proximate to a downhole end of theshaft 230. In one implementation, thevent 234 may open to themain flow area 220 at a location between the turbine stages 240 and thethrust bearings 260. In another implementation, thevent 234 may open to themain flow area 220 at a location downhole from thethrust bearings 260. - In operation, the
turbodrill 200 may receivedrilling fluid 270 from an uphole member of the drill string, where thedrilling fluid 270 may pass downhole through the one ormore flow ports 224. Most of thedrilling fluid 270 may pass through the turbine stages 240, whereby thedrilling fluid 270 may lose fluid pressure as it reaches a portion of themain flow area 220 proximate to thevent 234. A small amount of thedrilling fluid 270 may leak through a channel ormicroannulus 219 formed by aradial gap 280 between an inner diameter of thesleeve 217 and an outer diameter of thedrum rotor 214. Thus, theradial gap 280 provides a channel ormicroannulus 219 for thedrilling fluid 270 to leak from themain flow area 220 into thechannel 232. Further, a leak flow path may be defined frommain flow area 220 through themicroannulus 219, through thechannel 232 and through thevent 234. In one implementation, theradial gap 280 may have a maximum width and a minimum width. - The
radial gap 280 may also be of a width such that there is a fluid pressure differential across themicroannulus 219 between thechannel 232 and themain flow area 220 outside of thesleeve 217. In particular, theradial gap 280 may be of a size such that thedrilling fluid 270 is inhibited from exerting significant downhole thrust on an uphole end of theshaft 230. Thus, the fluid pressure inside thechannel 232 may be nearly equal to the fluid pressure of the portion of themain flow area 220 proximate to thevent 234, thereby producing the fluid pressure differential across themicroannulus 219 between thechannel 232 and themain flow area 220 outside of thesleeve 217. This fluid pressure differential may cause an uphole axial force to act on theshaft 230, offsetting the downhole thrust, and thereby approximately balancing an axial load applied to theshaft 230. Essentially, by reducing an amount of downhole thrust acting on theshaft 230, thebalance drum assembly 210 may reduce axial loading on thethrust bearings 260. - In one implementation, the one or more radial bearings and/or the one or
more thrust bearings 260 may each have a clearance with theshaft 230 that is greater than theradial gap 280. For example, each radial bearing and each thrust bearing 260 may have a clearance with theshaft 230 of about 0.004-0.005 inches, while theradial gap 280 may be about 0.001 inches. - During directional drilling, the
turbodrill 200 may be forced to flex, such as when it passes through high doglegs. This flexing may force the components of thebalance drum assembly 210 to behave as a bearing, such as by inducing a load within thedrum stator 212 and possibly canting thedrum rotor 214 within thedrum stator 212. Thedrum rotor 214 and/or thedrum stator 212 may then wear due to friction, causing thebalance drum assembly 210 to lose effectiveness in maintaining the fluid pressure differential across themicroannulus 219 between thechannel 232 and themain flow area 220 outside of thesleeve 217. Various implementations may be used to minimize the canting of thedrum rotor 214 within thedrum stator 212. - Balance Drum Assembly with a Compliant Mounting
-
FIGS. 3-8 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with a compliant mounting in accordance with implementations of various techniques described herein. The compliant mounting may allow for some movement of the balance drum assembly. - In this implementation, the turbodrill may use a balance drum assembly with a compliant mounting, where the compliant mounting may be a spring mechanism. The spring mechanism may be a coil spring, one or more Belleville springs, a machine spring, a wave spring, or any other spring mechanism known to those skilled in the art.
-
FIG. 3 illustrates a cross-sectional view of aturbodrill 300 using abalance drum assembly 310 with acoil spring 390 in accordance with implementations of various techniques described herein. Theturbodrill 300 may include ahousing 302, where thehousing 302 may have an upper connection for engaging with uphole members of a drill string. - The
balance drum assembly 310 may be similar to thebalance drum assembly 210, where thebalance drum assembly 310 may be disposed within amain flow area 320 of theturbodrill 300 and may include adrum stator 312 and adrum rotor 314. Thedrum stator 312 may also include acap 315 having one ormore flow ports 324, where the one ormore flow ports 324 allow drilling fluid to pass through themain flow area 320. Thedrum stator 312 may also include asleeve 317 descending from thecap 315 in adownhole direction 301, where thedrum rotor 314 may be movably disposed within thesleeve 317. - Similar to the
drum rotor 214, thedrum rotor 314 may be hollow and configured to rotate within thehousing 302. Specifically, thedrum rotor 314 may be configured to rotate within thesleeve 317. Thedrum rotor 314 may be coupled to an uphole end of a shaft (not shown), such that thedrum rotor 314 may be configured to rotate in conjunction with the shaft. The shaft may also be hollow such that achannel 332 may be formed with thedrum rotor 314. Aradial gap 380 similar to theradial gap 280 may be formed between an inner diameter of thesleeve 317 and an outer diameter of thedrum rotor 314. In one implementation, theradial gap 380 may be about 0.001 inches to about 0.01 inches. - In contrast to the
balance drum assembly 210, thebalance drum assembly 310 may not be fixed to thehousing 302. Instead, thebalance drum assembly 310 may be coupled to thecoil spring 390, where thecoil spring 390 may be coupled to thehousing 302. In particular, a downhole end of thecap 315 may be coupled to an uphole end of thecoil spring 390. Thecap 315 may be coupled to thecoil spring 390 through bonding, clamping, bolting, or any other implementation known to those skilled in the art. In turn, a downhole end of thecoil spring 390 may be coupled to aninner shoulder 360 of thehousing 302. Thecoil spring 390 may be coupled to theinner shoulder 360 through bonding, clamping, bolting, or any other implementation known to those skilled in the art. In one implementation, theinner shoulder 360 may include an internal nut, bolt, or screw attached to thehousing 302. - In another implementation, an outer diameter of the
cap 315 may be less than an internal diameter of themain flow area 320. An outer diameter of thecoil spring 390 may also be less than the internal diameter of themain flow area 320. In particular, space may exist between thecap 315 and an inner wall of thehousing 302 such that thecoil spring 390 may allow for a lateral displacement and an angular displacement of thebalance drum assembly 310 within thehousing 302. - In one implementation, lateral displacement of the
balance drum assembly 310 may occur when a central axis of thebalance drum assembly 310 is misaligned from a central axis of thehousing 302 by a uniform distance. In such an implementation, thecoil spring 390 may allow for the lateral displacement of thebalance drum assembly 310 via lateral shifting of coils in thecoil spring 390. In another implementation, angular displacement of thebalance drum assembly 310 may occur when the central axis of thebalance drum assembly 310 is misaligned from the central axis of thehousing 302 by non-uniform distances, such that the central axis of thebalance drum assembly 310 forms an angle with the central axis of thehousing 302. In such an implementation, thecoil spring 390 may allow for the angular displacement of thebalance drum assembly 310 by compressing one side of thecoil spring 390 more than the other. - In the cases of directional drilling or curved drilling tools, the lateral and angular displacement via
coil spring 390 may lessen the likelihood of point loading due to canting within thebalance drum assembly 310, thereby avoiding wear along theradial gap 380. In one implementation, theturbodrill 300 may allow for up to about 10 millimeters in lateral displacement of thebalance drum assembly 310 within thehousing 302. In another implementation, theturbodrill 300 may allow for up to about 10 degrees of angular displacement of thebalance drum assembly 310 within thehousing 302. - In a further implementation of the
balance drum assembly 310, thecap 315 and thecoil spring 390 may be designed such that they are placed further downhole along thesleeve 317. For example,FIGS. 4 and 5 illustrate cross-sectional views of theturbodrill 300 using thebalance drum assembly 310 with thecoil spring 390, where thecaps 315 and the coil springs 390 are placed further downhole along thesleeve 317 in comparison toFIG. 3 . - In another implementation, referring back to
FIG. 3 , thecap 315 may be coupled to thecoil spring 390 such that torsion of thecoil spring 390 resists rotation of thedrum stator 312 within thehousing 302 in response to a flow of the drilling fluid. In such an implementation, while thedrum rotor 314 may rotate in conjunction with the shaft, thedrum stator 312 may remain largely stationary within thehousing 302. Thecoil spring 390 may also be configured to resist a downhole thrust resulting from the flow of the drilling fluid. - Spring Mechanism with Rotational Inhibitors
- In this implementation, the turbodrill may use a balance drum assembly having one or more rotational inhibitors in addition to the spring mechanism. As previously mentioned, the spring mechanism may be a coil spring, one or more Belleville springs, a machine spring, a wave spring, or any other spring mechanism known to those skilled in the art.
-
FIG. 6 illustrates a cross-sectional view of aturbodrill 600 using a balance drum assembly 610 with one or more Belleville springs 690 and one or morerotational inhibitors 695 in accordance with implementations of various techniques described herein. Theturbodrill 600 may include ahousing 602, where thehousing 602 may have an upper connection for engaging with uphole members of a drill string. The balance drum assembly 610 may include the same/similar components and configuration as thebalance drum assembly 310 described with reference toFIG. 3 , e.g., a drum rotor 614, adrum stator 612 having acap 615 and asleeve 617. - In one implementation, the balance drum assembly 610 may rest on the one or more Belleville springs 690, which in turn rest on an inner shoulder 660 of the
housing 602. In particular, a downhole end of thecap 615 may rest on an uphole end of the one or more Belleville springs 690. In turn, a downhole end of the one or more Belleville springs 690 may rest on the inner shoulder 660 of thehousing 602. It should be understood that the inner shoulder 660 is similar to theinner shoulder 360. The one or more Belleville springs 690 may be configured to resist a downhole thrust resulting from a flow of drilling fluid. - One or more
rotational inhibitors 695 may be used to resist rotation of thedrum stator 612 within thehousing 602 in response to the flow of drilling fluid. Therotational inhibitors 695 may be coupled to an inner wall of thehousing 602 and may be linked to thecap 615 such that rotation of thedrum stator 612 is restrained. In one implementation, therotational inhibitors 695 may include one or more pins or springed pins having a first end coupled to thehousing 602 and a second end engaging thecap 615, e.g., resting within a respective gap of thecap 615. Theturbodrill 600 may be configured such that each pin or springed pin would rest within a particular gap of thecap 615. Upon an application of rotational force on thedrum stator 612, thecap 615 may rotate a minimal distance until a pin or springed pin comes into contact with an edge of its particular gap. In another implementation, therotational inhibitors 695 may include one or more cables having a first end coupled to thehousing 602 and a second end coupled to thecap 615. Rotation of thecap 615 would be limited by a length of the one or more cables. In a further implementation, the one or more cables may be made using steel or any other implementation known to those skilled in the art. - In a further implementation, a lateral displacement and an angular displacement of the balance drum assembly 610 within the
housing 602 may be achieved similarly to the lateral displacement and the angular displacement of thebalance drum assembly 310 within thehousing 302, as therotational inhibitors 695 may be configured to offer no resistance to the lateral and angular displacement of the balance drum assembly 610. Similar to thecoil spring 390, the lateral and angular displacement via the one or more Belleville springs 690 may lessen the likelihood of point loading caused by canting within the balance drum assembly 610, thereby avoiding wear along a radial gap formed between the inner diameter of thesleeve 617 and the outer diameter of the drum rotor 614. - In particular, in one implementation, lateral displacement of the balance drum assembly 610 may occur when a central axis of the balance drum assembly 610 is misaligned from a central axis of the
housing 602 by a uniform distance. In such an implementation, the one or more Belleville springs 690 may allow for the lateral displacement of the balance drum assembly 610 via lateral shifting of springs in the one or more Belleville springs 690. In another implementation, angular displacement of the balance drum assembly 610 may occur when the central axis of the balance drum assembly 610 is misaligned from the central axis of thehousing 602 by non-uniform distances, such that the central axis of the balance drum assembly 610 forms an angle with the central axis of thehousing 602. In such an implementation, the one or more Belleville springs 690 may allow for the angular displacement of the balance drum assembly 610 by compressing one side of the one or more Belleville springs 690 more than the other. - In this implementation, the turbodrill may use a balance drum assembly with a compliant mounting constructed of a solid material. In such an implementation, the compliant mounting may be an elastomeric mounting, such as a rubber mounting, a mounting composed of polytetrafluoroethylene (PTFE), or any other elastomeric mounting known to those skilled in the art.
-
FIG. 7 illustrates a cross-sectional view of aturbodrill 700 using a balance drum assembly 710 with an elastomeric mounting 790 in accordance with implementations of various techniques described herein. In one implementation, the elastomeric mounting 790 may be composed of rubber. Theturbodrill 700 may include ahousing 702, where thehousing 702 may have an upper connection for engaging with uphole members of a drill string. The balance drum assembly 710 may include the same/similar components and configurations as thebalance drum assembly 310, e.g., adrum rotor 714 and adrum stator 712 having acap 715 and asleeve 717. - The balance drum assembly 710 may be coupled to the elastomeric mounting 790, where the elastomeric mounting 790 is coupled to the
housing 702. In one implementation, the elastomeric mounting 790 may include atop portion 791 coupled to abottom portion 792. The elastomeric mounting 790 may be oriented such that thetop portion 791 is uphole relative to thebottom portion 792. Thetop portion 791 may be disposed between an inner wall of thehousing 702 and thecap 715. Thetop portion 791 may be coupled to thehousing 702 and to thecap 715 using a bonding or any other implementation known to those in the art. - The
bottom portion 792 may be disposed between aninner shoulder 760 of thehousing 702 and the downhole ends of thecap 715 and thetop portion 791. A downhole end of thebottom portion 792 may be coupled to theinner shoulder 760, and an uphole end of thebottom portion 792 may be coupled to the downhole ends of thecap 715 and thetop portion 791. Thebottom portion 792 may be coupled using a bonding or any other implementation known to those in the art. The coupling of thetop portion 791 and thebottom portion 792 to thecap 715 may help resist rotation of thedrum stator 712 within thehousing 702 in response to a flow of drilling fluid. - In one implementation, the
top portion 791 may have more compliance and/or flexibility than thebottom portion 792. In another implementation, thetop portion 791 and thebottom portion 792 may constitute one piece and may consist of material having the same compliance and/or flexibility. In yet another implementation, theinner shoulder 760 may include an internal nut, bolt, or screw attached to the housing. - The
top portion 791 and thebottom portion 792 of the elastomeric mounting 790 may possess sufficient compliance and/or flexibility to allow for a lateral displacement and an angular displacement of the balance drum assembly 710 within thehousing 702. Similar to thecoil spring 390, the lateral and angular displacement via the elastomeric mounting 790 may lessen the likelihood of point loading caused by canting within the balance drum assembly 710, thereby avoiding wear along the radial gap. - In particular, in one implementation, lateral displacement of the balance drum assembly 710 may occur when a central axis of the balance drum assembly 710 is misaligned from a central axis of the
housing 702 by a uniform distance. In such an implementation, the elastomeric mounting 790 may allow for the lateral displacement of the balance drum assembly 710 via compression of thetop portion 791 and/or thebottom portion 792. In another implementation, angular displacement of the balance drum assembly 710 may occur when the central axis of the balance drum assembly 710 is misaligned from the central axis of thehousing 702 by non-uniform distances, such that the central axis of the balance drum assembly 710 forms an angle with the central axis of thehousing 702. In such an implementation, the elastomeric mounting 790 may allow for the angular displacement of the balance drum assembly 710 by compressing one side of thetop portion 791 and/or thebottom portion 792 more than the other. - In this implementation, the turbodrill may use a balance drum assembly with a compliant mounting, where the compliant mounting is a spherical bearing assembly. The spherical bearing assembly may be constructed of steel, or any other implementation known to those skilled in the art.
-
FIG. 8 illustrates a cross-sectional view of aturbodrill 800 using abalance drum assembly 810 with aspherical bearing assembly 890 in accordance with implementations of various techniques described herein. Theturbodrill 800 may include ahousing 802, where thehousing 802 may have an upper connection for engaging with uphole members of a drill string. Thebalance drum assembly 810 may include the same/similar components and configurations as thebalance drum assembly 310, e.g., adrum rotor 814 and adrum stator 812 having acap 815 and asleeve 817. In one implementation, aring 851 and/or a snap ring 852 may be coupled to an inner wall of thehousing 802, and may be positioned uphole relative to thecap 815 such that uphole movement of thedrum stator 812 may be relatively minimized within thehousing 802. - In one implementation, the
spherical bearing assembly 890 may include a topspherical seat 891 configured to mate to a bottomspherical seat 892. The topspherical seat 891 has an uphole end which may couple with the downhole end of thecap 815. The topspherical seat 891 has an outer diameter which may be smaller than an inner diameter of thehousing 802, such that aclearance 871 may be formed. The topspherical seat 891 may be coupled to thecap 815 using threads or any other coupling means known to those skilled in the art. In another implementation, the topspherical seat 891 and thecap 815 may constitute one piece and may be composed of the same material. In yet another implementation, the topspherical seat 891 may also have a portion which may be disposed between the inner wall of thehousing 802 and thecap 815. - A downhole end of the top
spherical seat 891 may be generally convex in shape and may be configured to mate with an uphole end of the bottomspherical seat 892, where the uphole end of the bottomspherical seat 892 may be generally concave in shape. A downhole end of the bottomspherical seat 892 may rest on aninner shoulder 860 of thehousing 802. An outer diameter of the bottomspherical seat 892 may be smaller than the inner diameter of thehousing 802, such that aclearance 872 may be formed. In one implementation, theclearance 872 may range from about 0.03 inches to 0.05 inches. - Lateral displacement of the
balance drum assembly 810 may occur when a central axis of thebalance drum assembly 810 is misaligned from a central axis of thehousing 802 by a uniform distance. In such an implementation,clearance 872 may allow for the lateral displacement of thebalance drum assembly 810 via lateral movement of thespherical bearing assembly 890. In particular, the bottomspherical seat 892 may be configured to move laterally along theinner shoulder 860, thereby allowing thespherical bearing assembly 890 and thebalance drum assembly 810 to also move laterally. In one implementation, the outer diameter of the bottomspherical seat 892 may be larger than the outer diameter of the topspherical seat 891, such that lateral displacement of the topspherical seat 891 and thebalance drum assembly 810 may be limited to the lateral displacement experienced by the bottomspherical seat 892. - Angular displacement of the
balance drum assembly 810 may occur when the central axis of thebalance drum assembly 810 is misaligned from the central axis of thehousing 802 by non-uniform distances, such that the central axis of thebalance drum assembly 810 forms an angle with the central axis of thehousing 802. In such an implementation, the convex shape of the downhole end of the topspherical seat 891 and the concave shape of the uphole end of the bottomspherical seat 892 may allow for the angular displacement of thebalance drum assembly 810. In particular, the topspherical seat 891 and the bottomspherical seat 892 may be configured to rotate with respect to one another, thereby allowing for angular displacement of thebalance drum assembly 810. - Balance Drum Assembly with Axial Bearings
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FIGS. 9-10 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with axial bearings in accordance with implementations of various techniques described herein. - Axial Bearings with Rotational Inhibitors
- In this implementation, the turbodrill may use a balance drum assembly with axial bearings and one or more rotational inhibitors. The axial bearings may be configured in an axial bearing cage having ball bearings, spherical contact bearings, tungsten carbide bearings, brass bearings, PDC surface bearings, or any other axial bearings known to those skilled in the art.
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FIG. 9 illustrates a cross-sectional view of aturbodrill 900 using abalance drum assembly 910 with anaxial bearing cage 985 and one or morerotational inhibitors 995 in accordance with implementations of various techniques described herein. Theturbodrill 900 may include ahousing 902, where thehousing 902 may have an upper connection for engaging with uphole members of a drill string. Thebalance drum assembly 910 may include the same/similar components and configurations as thebalance drum assembly 310 described inFIG. 3 , e.g., adrum rotor 914 and adrum stator 912 having acap 915 and asleeve 917. - In one implementation, the
balance drum assembly 910 may rest on theaxial bearing cage 985, where theaxial bearing cage 985 may also rest on aninner shoulder 960 of thehousing 902. In particular, a downhole end of thecap 915 may rest on an uphole end of theaxial bearing cage 985. In turn, a downhole end of theaxial bearing cage 985 may rest on theinner shoulder 960 of thehousing 902. In addition, thesleeve 917 may pass through aninner ring 986 of theaxial bearing cage 985, such that theinner ring 986 may be in contact with thesleeve 917. - Similar to the
rotational inhibitors 695, one or morerotational inhibitors 995 may be used to resist rotation of thedrum stator 912 within thehousing 902 in response to a flow of drilling fluid. Therotational inhibitors 995 may be coupled to an inner wall of thehousing 902 and may be linked to thecap 915 such that rotation of thedrum stator 912 is restrained. In one implementation, therotational inhibitors 995 may include one or more pins or springed pins having a first end coupled to thehousing 902 and a second end engaging thecap 915, e.g., resting within a respective gap of thecap 915. In another implementation, therotational inhibitors 995 may include one or more cables having a first end coupled to thehousing 902 and a second end coupled to thecap 915. - In one implementation, lateral displacement of the
balance drum assembly 910 may occur when a central axis of thebalance drum assembly 910 is misaligned from a central axis of thehousing 902 by a uniform distance. In such an implementation, bearings of theaxial bearing cage 985 may freely rotate and allow for the lateral displacement of thebalance drum assembly 910 within thehousing 902. Similar to therotational inhibitors 695, therotational inhibitors 995 may be configured to offer no resistance to the lateral displacement of thebalance drum assembly 910. However, the arrangement of theaxial bearing cage 985 and theinner shoulder 960 may prevent angular displacement of thebalance drum assembly 910 within thehousing 902. The lateral displacement via theaxial bearing cage 985 may still lessen the likelihood of point loading resulting from canting within thebalance drum assembly 910. - Axial Bearings with Rotational Inhibitors and Spring Mechanism
- In this implementation, the turbodrill may use a balance drum assembly with axial bearings, a spring mechanism, and one or more rotational inhibitors. The axial bearings may be configured in an axial bearing cage having ball bearings, tungsten carbide bearings, brass bearings, PDC surface bearings, or any other axial bearings known to those skilled in the art. The spring mechanism may be a coil spring, one or more Belleville springs, a machine spring, a wave spring, or any other spring mechanism known to those skilled in the art.
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FIG. 10 illustrates a cross-sectional view of aturbodrill 1000, using abalance drum assembly 1010 with anaxial bearing cage 1085, aspring mechanism 1090, and one or more rotational inhibitors 1095 in accordance with implementations of various techniques described herein. Theturbodrill 1000 may include ahousing 1002, where thehousing 1002 may have an upper connection for engaging with uphole members of a drill string. Thebalance drum assembly 1010 may include the same/similar components and configurations as thebalance drum assembly 310 described inFIG. 3 , e.g., adrum rotor 1014 and adrum stator 1012 having acap 1015 and asleeve 1017. - In one implementation, the
balance drum assembly 1010 may rest on theaxial bearing cage 1085, where theaxial bearing cage 1085 may rest on aspring mechanism 1090. In turn, thespring mechanism 1090 may rest on aninner shoulder 1060 of thehousing 1002. In particular, a downhole end of thecap 1015 may rest on an uphole end of theaxial bearing cage 1085. A downhole end of theaxial bearing cage 1085 may rest on an uphole end of thespring mechanism 1090, where a downhole end of thespring mechanism 1000 may rest on theinner shoulder 1060 of thehousing 1002. In addition, thesleeve 1017 may pass through aninner ring 1086 of theaxial bearing cage 1085, such that theinner ring 1086 may be in contact with thesleeve 1017. - Similar to the
rotational inhibitors 695, one or more rotational inhibitors 1095 may be used to resist rotation of thedrum stator 1012 within thehousing 1002 in response to a flow of drilling fluid. The rotational inhibitors 1095 may be coupled to an inner wall of thehousing 1002 and may be linked to thecap 1015 such that rotation of thedrum stator 1012 is restrained. In one implementation, the rotational inhibitors 1095 may include one or more pins or springed pins having a first end coupled to thehousing 1002 and a second end engaging thecap 1015, e.g., resting within a respective gap of thecap 1015. In another implementation, the rotational inhibitors 1095 may include one or more cables having a first end coupled to thehousing 1002 and a second end coupled to thecap 1015. - In one implementation, lateral displacement of the
balance drum assembly 1010 may occur when a central axis of thebalance drum assembly 1010 is misaligned from a central axis of thehousing 1002 by a uniform distance. In such an implementation, bearings of theaxial bearing cage 1085 may freely rotate and allow for the lateral displacement of thebalance drum assembly 1010 within thehousing 1002. In another implementation, thespring mechanism 1090 may allow for the lateral displacement of thebalance drum assembly 1010 via lateral shifting of springs in thespring mechanism 1090. Similar to therotational inhibitors 695, the rotational inhibitors 1095 may be configured to offer little or no resistance to the lateral displacement of thebalance drum assembly 1010. - In another implementation, angular displacement of the
balance drum assembly 1010 may occur when the central axis of thebalance drum assembly 1010 is misaligned from the central axis of thehousing 1002 by non-uniform distances, such that the central axis of thebalance drum assembly 1010 forms an angle with the central axis of thehousing 1002. In such an implementation, thespring mechanism 1090 may allow for the angular displacement of thebalance drum assembly 1010 by compressing one side of thespring mechanism 1090 more than the other. The lateral and angular displacement via thespring mechanism 1090 and/or theaxial bearing cage 1085 may lessen the likelihood of point loading caused by canting within thebalance drum assembly 1010, thereby avoiding wear along the radial gap. - Balance Drum Assembly with Compliant Rod Mechanism
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FIGS. 11-15 illustrate a cross-sectional view of a turbodrill using a balance drum assembly with a compliant rod mechanism in accordance with implementations of various techniques described herein. The compliant rod mechanism may allow for some movement of the balance drum assembly. - In this implementation, the compliant rod mechanism includes a flex rod and rod retainer.
FIG. 11 illustrates a cross-sectional view of aturbodrill 1100 using abalance drum assembly 1110 with aflex rod 1190 and arod retainer 1191 in accordance with implementations of various techniques described herein. Theturbodrill 1100 may include ahousing 1102, where thehousing 1102 may have an upper connection for engaging with uphole members of a drill string. - A
balance drum assembly 1110 may be disposed within amain flow area 1120 of theturbodrill 1100 and may include adrum stator 1112 and adrum rotor 1114. Thedrum rotor 1114 may be movably disposed within thedrum stator 1112. Thedrum rotor 1114 may also be hollow and configured to rotate within thehousing 1102. Specifically, thedrum rotor 1114 may be configured to rotate within thedrum stator 1112. Thedrum rotor 1114 may be coupled to an uphole end of a shaft (not shown), such that thedrum rotor 1114 may be configured to rotate in conjunction with the shaft. The shaft may also be hollow such that achannel 1132 may be formed with thedrum rotor 1114. Aradial gap 1180 similar to theradial gap 280 may be formed between an inner diameter of thedrum stator 1112 and an outer diameter of thedrum rotor 1114. - In contrast to the
balance drum assembly 210, thebalance drum assembly 1110 may not be fixed to thehousing 1102. Instead, thebalance drum assembly 1110 may be coupled to theflex rod 1190, where theflex rod 1190 is coupled to therod retainer 1191. Essentially, thebalance drum assembly 1110 hangs from therod retainer 1191 via theflex rod 1190. In particular, a downhole end of theflex rod 1190 may be coupled to an uphole end of thedrum stator 1112. Theflex rod 1190 may be coupled to thedrum stator 1112 through bonding, clamping, bolting, welding, threading, pinning, or any other implementation known to those skilled in the art. - In turn, an uphole end of the
flex rod 1190 may be coupled to a downhole end of therod retainer 1191. Theflex rod 1190 may be coupled to therod retainer 1191 through bonding, clamping, bolting, welding, threading, or any other implementation known to those skilled in the art. Like thecap 315, therod retainer 1191 may have one ormore flow ports 1124 for allowing drilling fluid to pass through themain flow area 1120. The downhole end of therod retainer 1191 may be disposed on aninner shoulder 1160 of thehousing 1102. Theinner shoulder 1160 may include an internal nut, bolt, or screw attached to thehousing 1102. - In one implementation, an outer diameter of the
drum stator 1112 may be less than an internal diameter of themain flow area 1120. In particular, space may exist between thedrum stator 1112 and an inner wall of thehousing 1102 such that theflex rod 1190 may allow for a lateral displacement and an angular displacement of thebalance drum assembly 1110 within thehousing 1102. Theflex rod 1190 may be a cable attachment, a coil spring, a rod composed of titanium, flexible steel, or any other compliant material known to those skilled in the art which would allow displacement of thebalance drum assembly 1110 within thehousing 1102. In one implementation, in order to maximize compliance and/or flexibility of theflex rod 1190, theflex rod 1190 may be designed to be as long and as thin as allowed under the design constraints for theturbodrill 1100. - As mentioned above, lateral displacement of the
balance drum assembly 1110 may occur when a central axis of thebalance drum assembly 1110 is misaligned from a central axis of thehousing 1102 by a uniform distance. Accordingly, theflex rod 1190 may allow for the lateral displacement of thebalance drum assembly 1110 via bending of theflex rod 1190. - Likewise, angular displacement of the
balance drum assembly 1110 may occur when the central axis of thebalance drum assembly 1110 is misaligned from the central axis of thehousing 1102 by non-uniform distances, such that the central axis of thebalance drum assembly 1110 forms an angle with the central axis of thehousing 1102. Accordingly, theflex rod 1190 may allow for the angular displacement of thebalance drum assembly 1110 via bending of theflex rod 1190. In the cases of directional drilling or curved drilling tools, the lateral and angular displacement via theflex rod 1190 may lessen the likelihood of point loading caused by canting within thebalance drum assembly 1110, thereby avoiding wear along theradial gap 1180. - In one implementation, torsion of the
flex rod 1190 may resist rotation of thedrum stator 1112 within thehousing 1102 in response to a flow of the drilling fluid. In addition, therod retainer 1191 may be largely stationary within thehousing 1102. In such an implementation, while thedrum rotor 1114 rotates in conjunction with the shaft, thedrum stator 1112 may remain largely stationary within thehousing 1102. Theflex rod 1190 may also be configured to handle a downhole thrust resulting from the flow of the drilling fluid. In implementations where theflex rod 1190 may be of a lower torsion, one or more rotational inhibitors, such as those discussed with respect toFIG. 6 , may be used to restrain rotation of thedrum stator 1112. - Rod with Compliant Joints
- In this implementation, the compliant rod mechanism includes a rod, a rod retainer, and one or more compliant joints. In such an implementation, the one or more compliant joints may include a universal joint, a constant-velocity (CV) joint, or any other compliant joint known to those skilled in the art.
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FIG. 12 illustrates a cross-sectional view of aturbodrill 1200 using abalance drum assembly 1210 with arod 1290, a loweruniversal joint 1293, and an upper universal joint 1295 in accordance with implementations of various techniques described herein. Theturbodrill 1200 may include ahousing 1202, where thehousing 1202 may have an upper connection for engaging with uphole members of a drill string. - The
balance drum assembly 1210 may be disposed within thehousing 1202, and may include adrum rotor 1214 and adrum stator 1212. It should be understood that thehousing 1202 is similar to thehousing 1002, and thebalance drum assembly 1210 is similar to thebalance drum assembly 1010. In particular, thedrum rotor 1214 is similar to thedrum rotor 1114, and thedrum stator 1212 is similar to thedrum stator 1112. Theturbodrill 1200 may also include arod retainer 1291 similar to therod retainer 1191. - The
balance drum assembly 1210 may be coupled to therod 1290 via the loweruniversal joint 1293, where therod 1290 is coupled to therod retainer 1291 via the upperuniversal joint 1295. Essentially, thebalance drum assembly 1210 hangs from therod retainer 1291 via therod 1090, the loweruniversal joint 1293, and the upperuniversal joint 1295. In particular, a downhole end of therod 1290 may be coupled to an uphole end of thedrum stator 1212 via the loweruniversal joint 1293. - In turn, an uphole end of the
rod 1290 may be coupled to a downhole end of therod retainer 1291 via the upperuniversal joint 1295. The downhole end of therod retainer 1291 may also be disposed on an inner shoulder 1260 of thehousing 1202. In one implementation, the inner shoulder 1260 may be similar to theinner shoulder 1160. In a further implementation, therod 1290 may be composed of any material known to those skilled in the art which would support the configuration of thebalance drum assembly 1210 within thehousing 1202 as described herein. - As previously mentioned, lateral displacement of the
balance drum assembly 1210 may occur when a central axis of thebalance drum assembly 1210 is misaligned from a central axis of thehousing 1202 by a uniform distance. Accordingly, thebalance drum assembly 1210 may be laterally displaced through pivoting of both the loweruniversal joint 1293 and the upperuniversal joint 1295. - Likewise, angular displacement of the
balance drum assembly 1210 may occur when the central axis of thebalance drum assembly 1210 is misaligned from the central axis of thehousing 1202 by non-uniform distances, such that the central axis of thebalance drum assembly 1210 forms an angle with the central axis of thehousing 1202. Accordingly, thebalance drum assembly 1210 may be angularly displaced through pivoting of either the lower universal joint 1293 or the upperuniversal joint 1295. In the cases of directional drilling or curved drilling tools, the lateral and angular displacement via the loweruniversal joint 1293 and the upper universal joint 1295 may lessen the likelihood of point loading caused by canting within thebalance drum assembly 1210, thereby avoiding wear along the radial gap formed between an inner diameter of thedrum stator 1212 and an outer diameter of thedrum rotor 1214. - In one implementation, the
rod 1290, the loweruniversal joint 1293, and the upper universal joint 1295 may be configured to resist rotation of thedrum stator 1212 within thehousing 1202 in response to a flow of the drilling fluid. Therod 1290, the loweruniversal joint 1293, and the upper universal joint 1295 may also be configured to handle a downhole thrust resulting from the flow of the drilling fluid. - In this implementation, the turbodrill may use a balance drum assembly with a compliant rod mechanism, where the compliant rod mechanism may include a flex shaft.
FIG. 13 illustrates a cross-sectional view of aturbodrill 1300 using abalance drum assembly 1310 with aninternal flex shaft 1390 in accordance with implementations of various techniques described herein. Theturbodrill 1300 may include ahousing 1302, where thehousing 1302 may have an upper connection for engaging with uphole members of a drill string. - A
balance drum assembly 1310 may be disposed within amain flow area 1320 of theturbodrill 1300 and may include adrum stator 1312 and adrum rotor 1314. Thedrum stator 1312 may include acap 1315 and asleeve 1317 descending from thecap 1315 in adownhole direction 1301. An uphole end of thecap 1315 may have openings for one ormore flow ports 1324, where the one ormore flow ports 1324 allow drilling fluid to pass in thedownhole direction 1301 through one or more channels in thesleeve 1317 and to themain flow area 1320. - The
drum stator 1312 may be largely stationary within thehousing 1302. In particular, a downhole end of thesleeve 1317 may be disposed on aninner shoulder 1360 of thehousing 1302. In one implementation, theinner shoulder 1360 may include an internal nut, bolt, or screw attached to thehousing 1302. Thedrum rotor 1314 may be movably disposed within thesleeve 1317, where thedrum rotor 1314 may be hollow and configured to rotate. Specifically, thedrum rotor 1314 may be configured to rotate within thesleeve 1317. Further, aradial gap 1380, similar to theradial gap 280, may be formed between an inner diameter of thesleeve 1317 and an outer diameter of thedrum rotor 1314. - The
drum rotor 1314 may be coupled to an uphole end of theinternal flex shaft 1390, such that thedrum rotor 1314 may be configured to rotate in conjunction with theinternal flex shaft 1390. In particular, the uphole end of theinternal flex shaft 1390 may be coupled to thedrum rotor 1314 within adrum rotor annulus 1318 and within thesleeve 1317, where thedrum rotor annulus 1318 may be defined by an inner bore of thedrum rotor 1314. - In turn, a downhole end of the
internal flex shaft 1390 may be coupled to an uphole end of amain shaft 1330, where themain shaft 1330 may extend in adownhole direction 1301 through theturbodrill 1300 and may be coupled to a drill bit (not shown). In addition, theinternal flex shaft 1390 and themain shaft 1330 may both be hollow such that achannel 1332 may be formed with thedrum rotor 1314. Theinternal flex shaft 1390 may be configured to rotate in conjunction with themain shaft 1330. In another implementation, theinternal flex shaft 1390 may be coupled to themain shaft 1330 and to thedrum rotor 1314 using threads, screws, bolts, or any other coupling mechanism known to those skilled in the art. - In one implementation, space may exist within the
main flow area 1320 and/or thedrum rotor annulus 1318 such that theinternal flex shaft 1390 may allow for a lateral displacement and an angular displacement of themain shaft 1330 within thehousing 1302. As mentioned above, lateral displacement of themain shaft 1330 may occur when a central axis of themain shaft 1330 is misaligned from a central axis of thehousing 1302 by a uniform distance. In such an instance, theinternal flex shaft 1390 may allow for the lateral displacement of themain shaft 1330 via bending of theinternal flex shaft 1390. - Likewise, angular displacement of the
main shaft 1330 may occur when the central axis of themain shaft 1330 is misaligned from the central axis of thehousing 1302 by non-uniform distances, such that the central axis of themain shaft 1330 forms an angle with the central axis of thehousing 1302. In such an instance, theinternal flex shaft 1390 may allow for the angular displacement of themain shaft 1330 via bending of theinternal flex shaft 1390. In the cases of directional drilling or curved drilling tools, the lateral and angular displacement via theinternal flex shaft 1390 may lessen the likelihood of point loading caused by canting within thebalance drum assembly 1310, thereby avoiding wear along theradial gap 1380. In one implementation, the bending of theinternal flex shaft 1390 may occur within thedrum rotor annulus 1318. - In one implementation, the flex shaft may be coupled to the
drum rotor 1314 further downhole along theturbodrill 1300. For example,FIG. 14 illustrates a cross-sectional view of theturbodrill 1300 using thebalance drum assembly 1310 with anexternal flex shaft 1490 in accordance with implementations of various techniques described herein. In such an implementation, an uphole end of theexternal flex shaft 1490 may be coupled to a downhole end of thedrum rotor 1314 located outside of thesleeve 1317. In a further implementation, theflex shafts main shaft 1330 within thehousing 1302. - In another implementation, one or more vents 1334 may be placed proximate to the
balance drum assembly 1310. For example,FIG. 15 illustrates a cross-sectional view of theturbodrill 1300 using thebalance drum assembly 1310 with theinternal flex shaft 1390 in accordance with implementations of various techniques described herein. The vents 1334 may be positioned along thehousing 1302, such that the vents open to an area outside of theturbodrill 1300. In particular, this area is formed by an outer diameter of thehousing 1302 and an inner wall of a borehole in which theturbodrill 1300 is placed. This area may have lower fluid pressure relative to amain flow area 1320 of theturbodrill 1300. - The vents 1334 may be connected to a channel 1333 formed within the
cap 1315 of thedrum stator 1312, leading to a microannulus 1319. The microannulus 1319 may be similar to themicroannulus 219, and may be defined by thedrum rotor 1314 within thesleeve 1317. In operation, drilling fluid may leak from themain flow area 1320, through theradial gap 1380, and into the microannulus 1319. However, while in the microannulus 1319, the drilling fluid may be prevented from exerting significant downhole thrust on an uphole end of theinternal flex shaft 1390 due to the connection between the vents 1334 and the microannulus 1319. Essentially, the connection to the lower pressure area outside of theturbodrill 1300 may mitigate downhole thrust acting on theinternal flex shaft 1390, and therefore, thebalance drum assembly 1310 may reduce axial loading on any thrust bearings. In a further implementation, theinternal flex shaft 1390 and/or the main shaft 1330 (not pictured) may be composed of solid material, such that, unlikeshaft 230 ofFIG. 2 , theinternal flex shaft 1390 and/or themain shaft 1330 may not be hollow. - The turbodrills and their respective balance drum assemblies described above with respect to
FIGS. 1-15 allow for the turbodrills to follow angular deflections of the shaft, whether from a curved design or from directional drilling. The lateral and angular displacement used in the turbodrills above may lessen the likelihood of point loading due to canting within the balance drum assemblies. The turbodrills above are also arranged and designed to handle a downhole thrust resulting from a flow of drilling fluid through the tools. - While the foregoing is directed to implementations of various techniques described herein, other and further implementations may be devised without departing from the basic scope thereof. Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.
Claims (45)
1. A turbodrill, comprising:
a housing having an upper end that is configured to be coupled to a drill string;
a rotatable shaft having a lower end configured to be coupled to a drill bit;
a balance drum assembly coupled to the shaft within the housing; and
a compliant mounting disposed between the balance drum assembly and the housing, wherein the compliant mounting is configured to allow displacement of the balance drum assembly within the housing.
2. The turbodrill of claim 1 , wherein the balance drum assembly comprises:
a drum rotor coupled to the shaft, wherein the drum rotor is configured to rotate with the shaft; and
a drum stator coupled to the drum rotor and comprising a cap, wherein the compliant mounting is disposed between the cap and the housing.
3. The turbodrill of claim 2 , wherein an uphole end of the compliant mounting is coupled to a downhole end of the cap, and wherein a downhole end of the compliant mounting is coupled to an inner shoulder of the housing.
4. The turbodrill of claim 2 , wherein the compliant mounting is configured to resist rotation of the drum stator within the housing.
5. The turbodrill of claim 1 , wherein the compliant mounting comprises a coil spring, a Belleville spring, a machine spring, or a wave spring.
6. The turbodrill of claim 1 , wherein the compliant mounting is configured to allow lateral displacement of the balance drum assembly relative to a central axis of the housing.
7. The turbodrill of claim 1 , wherein the compliant mounting is configured to allow angular displacement of the balance drum assembly relative to a central axis of the housing.
8. The turbodrill of claim 1 , further comprising one or more rotational inhibitors coupled between the housing and the balance drum assembly, wherein the rotational inhibitors are configured to restrain the balance drum assembly.
9. The turbodrill of claim 8 , wherein the rotational inhibitors are configured to resist rotation of a drum stator within the housing.
10. The turbodrill of claim 8 , wherein the one or more rotational inhibitors have a first end coupled to the housing and a second end engaging the cap.
11. The turbodrill of claim 8 , wherein the one or more rotational inhibitors comprise one or more pins, one or more springed pins, one or more cables, or combinations thereof.
12. A turbodrill, comprising:
a housing having an upper end that is configured to be coupled to a drill string;
a rotatable shaft having a lower end configured to be coupled to a drill bit;
a balance drum assembly coupled to the shaft within the housing; and
an elastomeric mounting disposed between the balance drum assembly and the housing, wherein the elastomeric mounting is configured to allow displacement of the balance drum assembly within the housing.
13. The turbodrill of claim 12 , wherein the balance drum assembly comprises:
a drum rotor coupled to the shaft, wherein the drum rotor is configured to rotate with the shaft; and
a drum stator coupled to the drum rotor and comprising a cap, wherein the elastomeric mounting is disposed between the cap and the housing.
14. The turbodrill of claim 13 , wherein a top portion of the elastomeric mounting is coupled to the cap and to an inner wall of the housing.
15. The turbodrill of claim 14 , wherein a bottom portion of the elastomeric mounting comprises:
a downhole end coupled to an inner shoulder of the housing; and
an uphole end coupled to a downhole end of the cap and a downhole end of the top portion.
16. The turbodrill of claim 15 , wherein the top portion has greater flexibility than the bottom portion.
17. The turbodrill of claim 12 , wherein the elastomeric mounting is configured to allow lateral displacement of the balance drum assembly relative to a central axis of the housing.
18. The turbodrill of claim 12 , wherein the elastomeric mounting is configured to allow angular displacement of the balance drum assembly relative to a central axis of the housing.
19. A turbodrill, comprising:
a housing having an upper end that is configured to be coupled to a drill string;
a rotatable shaft having a lower end configured to be coupled to a drill bit;
a balance drum assembly coupled to the shaft within the housing; and
a compliant rod mechanism coupled to an uphole end of the balance drum assembly, wherein the compliant rod mechanism is configured to allow displacement of the balance drum assembly within the housing.
20. The turbodrill of claim 19 , wherein the balance drum assembly comprises:
a drum rotor coupled to the shaft, wherein the drum rotor is configured to rotate with the shaft; and
a drum stator coupled to the drum rotor, wherein the drum stator is disposed between the compliant rod mechanism and the drum rotor.
21. The turbodrill of claim 19 , wherein the compliant rod mechanism comprises:
a flex rod having a downhole end coupled to the drum stator; and
a rod retainer having a downhole end coupled to the flex rod, wherein the rod retainer is disposed on an inner shoulder of the housing.
22. The turbodrill of claim 21 , wherein the flex rod comprises a cable attachment, a coil spring, a rod composed of titanium, or flexible steel.
23. The turbodrill of claim 21 , wherein the flex rod is configured to resist rotation of the drum stator within the housing.
24. The turbodrill of claim 19 , wherein the compliant rod mechanism is configured to allow lateral displacement or angular displacement of the balance drum assembly relative to a central axis of the housing.
25. The turbodrill of claim 24 , wherein the compliant rod mechanism is configured to allow the lateral displacement or angular displacement via bending of the compliant rod mechanism.
26. A turbodrill, comprising:
a housing having an upper end that is configured to be coupled to a drill string;
a rotatable shaft having a lower end configured to be coupled to a drill bit;
a balance drum assembly coupled to the shaft within the housing; and
a rod with one or more compliant joints coupled to an uphole end of the balance drum assembly, wherein the rod with one or more compliant joints is configured to allow displacement of the balance drum assembly within the housing.
27. The turbodrill of claim 26 , wherein the balance drum assembly comprises:
a drum rotor coupled to the shaft, wherein the drum rotor is configured to rotate with the shaft; and
a drum stator coupled to the drum rotor, wherein the drum stator is disposed between the rod with one or more compliant joints and the drum rotor.
28. The turbodrill of claim 26 , wherein the rod with one or more compliant joints comprises:
a rod having a downhole end coupled to the drum stator via a lower compliant joint; and
a rod retainer having a downhole end coupled to the rod via an upper compliant joint, wherein the rod retainer is disposed on an inner shoulder of the housing.
29. The turbodrill of claim 26 , wherein the one or more compliant joints comprise one or more universal joints or one or more constant-velocity (CV) joints.
30. The turbodrill of claim 26 , wherein the rod with one or more compliant joints is configured to allow lateral displacement or angular displacement of the balance drum assembly relative to a central axis of the housing.
31. The turbodrill of claim 30 , wherein the rod with one or more compliant joints is configured to allow the lateral displacement or angular displacement via pivoting of the one or more compliant joints.
32. A turbodrill, comprising:
a housing having an upper end that is configured to be coupled to a drill string;
a rotatable shaft having a lower end configured to be coupled to a drill bit;
a balance drum assembly coupled to the shaft within the housing; and
a flex shaft having an uphole end coupled to the balance drum assembly and a downhole end coupled to the rotatable shaft, wherein the flex shaft is configured to allow displacement of the balance drum assembly within the housing.
33. The turbodrill of claim 32 , wherein the balance drum assembly comprises:
a drum rotor coupled to the uphole end of the flex shaft, wherein the drum rotor is configured to rotate with the flex shaft; and
a drum stator coupled to the drum rotor and comprising a cap and a sleeve, wherein the sleeve is disposed on an inner shoulder of the housing.
34. The turbodrill of claim 33 , wherein the drum rotor is coupled to the uphole end of the flex shaft within an inner bore of the drum rotor.
35. The turbodrill of claim 33 , wherein the drum rotor is coupled to the uphole end of the flex shaft outside of an inner bore of the drum rotor.
36. The turbodrill of claim 32 , wherein the flex shaft is configured to allow lateral displacement or angular displacement of the balance drum assembly relative to a central axis of the housing.
37. The turbodrill of claim 36 , wherein the flex shaft is configured to allow the lateral displacement or angular displacement via bending of the flex shaft.
38. The turbodrill of claim 32 , wherein one or more vents are placed proximate to the balance drum assembly.
39. A turbodrill, comprising:
a housing having an upper end that is configured to be coupled to a drill string;
a rotatable shaft having a lower end configured to be coupled to a drill bit;
a balance drum assembly coupled to the shaft within the housing; and
a spherical bearing assembly disposed between the balance drum assembly and the housing, wherein the spherical bearing assembly is configured to allow displacement of the balance drum assembly within the housing.
40. The turbodrill of claim 39 , wherein the balance drum assembly comprises:
a drum rotor coupled to the shaft, wherein the drum rotor is configured to rotate with the shaft; and
a drum stator coupled to the drum rotor and comprising a cap, wherein the spherical bearing assembly is disposed between the cap and the housing.
41. The turbodrill of claim 40 , wherein the spherical bearing assembly comprises a top spherical seat having a downhole end configured to mate to an uphole end of a bottom spherical seat.
42. The turbodrill of claim 41 , wherein the downhole end of the top spherical seat is generally convex, and wherein the uphole end of the bottom spherical seat is generally concave.
43. The turbodrill of claim 41 , wherein the downhole end of the bottom spherical seat is disposed on an inner shoulder of the housing.
44. The turbodrill of claim 41 , wherein a clearance formed by an outer diameter of the bottom spherical seat and an inner diameter of the housing is configured to allow for lateral displacement of the balance drum assembly.
45. The turbodrill of claim 41 , wherein the top spherical seat and the bottom spherical seat may be configured to rotate with respect to one another in order to allow for angular displacement of the balance drum assembly.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/843,684 US20140116785A1 (en) | 2012-11-01 | 2013-03-15 | Turbodrill Using a Balance Drum |
PCT/US2013/067928 WO2014071108A1 (en) | 2012-11-01 | 2013-11-01 | Turbodrill using a balance drum |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201261721410P | 2012-11-01 | 2012-11-01 | |
US13/843,684 US20140116785A1 (en) | 2012-11-01 | 2013-03-15 | Turbodrill Using a Balance Drum |
Publications (1)
Publication Number | Publication Date |
---|---|
US20140116785A1 true US20140116785A1 (en) | 2014-05-01 |
Family
ID=50545963
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/843,684 Abandoned US20140116785A1 (en) | 2012-11-01 | 2013-03-15 | Turbodrill Using a Balance Drum |
Country Status (2)
Country | Link |
---|---|
US (1) | US20140116785A1 (en) |
WO (1) | WO2014071108A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10607622B2 (en) | 2015-06-17 | 2020-03-31 | Samsung Electronics Co., Ltd. | Device and method for processing internal channel for low complexity format conversion |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4646856A (en) * | 1983-09-26 | 1987-03-03 | Dismukes Newton B | Downhole motor assembly |
US6629571B1 (en) * | 1998-01-28 | 2003-10-07 | Neyrfor-Weir Limited | Downhole motor assembly |
US20040200642A1 (en) * | 2000-06-21 | 2004-10-14 | Downie Andrew Mcpherson | Drilling turbine |
US20100307833A1 (en) * | 2009-06-08 | 2010-12-09 | Tempress Technologies, Inc. | Jet turbodrill |
US20120255724A1 (en) * | 2009-12-23 | 2012-10-11 | Hallundbaek Joergen | Downhole tool for borehole cleaning or for moving fluid in a borehole |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4679638A (en) * | 1985-03-13 | 1987-07-14 | Hughes Tool Company | Downhole progressive cavity type drilling motor with flexible connecting rod |
US5135059A (en) * | 1990-11-19 | 1992-08-04 | Teleco Oilfield Services, Inc. | Borehole drilling motor with flexible shaft coupling |
US6672409B1 (en) * | 2000-10-24 | 2004-01-06 | The Charles Machine Works, Inc. | Downhole generator for horizontal directional drilling |
US8607897B2 (en) * | 2009-10-29 | 2013-12-17 | Trican Well Service, Ltd. | Center discharge gas turbodrill |
-
2013
- 2013-03-15 US US13/843,684 patent/US20140116785A1/en not_active Abandoned
- 2013-11-01 WO PCT/US2013/067928 patent/WO2014071108A1/en active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4646856A (en) * | 1983-09-26 | 1987-03-03 | Dismukes Newton B | Downhole motor assembly |
US6629571B1 (en) * | 1998-01-28 | 2003-10-07 | Neyrfor-Weir Limited | Downhole motor assembly |
US20040200642A1 (en) * | 2000-06-21 | 2004-10-14 | Downie Andrew Mcpherson | Drilling turbine |
US20100307833A1 (en) * | 2009-06-08 | 2010-12-09 | Tempress Technologies, Inc. | Jet turbodrill |
US20120255724A1 (en) * | 2009-12-23 | 2012-10-11 | Hallundbaek Joergen | Downhole tool for borehole cleaning or for moving fluid in a borehole |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10607622B2 (en) | 2015-06-17 | 2020-03-31 | Samsung Electronics Co., Ltd. | Device and method for processing internal channel for low complexity format conversion |
Also Published As
Publication number | Publication date |
---|---|
WO2014071108A1 (en) | 2014-05-08 |
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