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
  • E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
  • E21B19/22—Handling reeled pipe or rod units, e.g. flexible drilling pipes

Definitions

• coil tube injector heads may be used to direct coil tubing (e.g., tubing which may be in a range of from approximately 1 " to approximately 3 1 ⁇ 2") into and out of a wellbore.
• the injectors provide a means of gripping the tubing to perform a controlled feeding operation.
• Injector heads are rated against the pushing/pulling force they can generate and the feedrate at which the tubing can be passed.
• a complete injector head may comprise several components.
• the injector head may include an injector head assembly; a crash frame (providing a degree of mechanical protection during service); a service platform (allowing the operators to manage the operation of coil tube injection during service); and a gooseneck (which controls the feed of the tubing into the injector from a separate coil tube spool).
• the basic premise of a coil tube injector is to simply grip the tubing with sufficient traction so that it does not slip when performing the desired subterranean operations, and then either pushing the tubing into a well or extracting it out.
• the drives are generally hydraulically powered and when combined with a reduction gearbox provide sufficient torque to adequately move the loads. It is desirable to have an injector head which can operate smoothly and which can be easily maintained and serviced without disrupting ongoing subterranean operations.
• Figure 1 is an illustration of a coil tube injector configuration in accordance with certain embodiments of the present disclosure.
• Figure 2A is a first perspective view of the injector head assembly of Figure 1 in accordance with an illustrative embodiment of the present disclosure.
• Figure 2B is a second perspective view of the injector head assembly of Figure 1 in accordance with an illustrative embodiment of the present disclosure.
• Figure 2C is a third perspective view of the injector head assembly of Figure 1 in accordance with an illustrative embodiment of the present disclosure.
• Figure 3 A is a side close up view of the injector head assembly of Figures 2A-C in accordance with certain embodiments of the present disclosure.
• Figure 3B is a cross-sectional view of the injector head assembly of Figure 3A in accordance with certain embodiments of the present disclosure.
• Figure 3C is a cross-sectional view of the injector head assembly of Figure 3A with one side of the crash frame removed, in accordance with certain embodiments of the present disclosure.
• Figure 4 is a close up view of one of the chain links of a gripper/chain assembly in accordance with certain embodiments of the present disclosure.
• Embodiments of the present disclosure may be used with any wellhead system.
• Embodiments of the present disclosure may be applicable to horizontal, vertical, deviated, or otherwise nonlinear wellbores in any type of subterranean formation.
• Embodiments may be applicable to injection wells as well as production wells, including hydrocarbon wells.
• Couple or “couples” as used herein are intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect mechanical or electrical connection via other devices and connections.
• the injector head unit may be an '80k' (80,000 psi) unit.
• the design concept can easily be upscaled and downscaled to suit the actual requirements.
• the methods and systems disclosed herein are directed to an actual operation constraint with regard to ease of operation and maintenance, making a 'simple' unit which is easily maintained and therefore, can be kept in production.
• a coil tube injector in accordance with an illustrative embodiment of the present disclosure is generally denoted with reference numeral 100 in Figure 1.
• a coil tube injector 100 is comprised of an injector head assembly 102, a crash frame 104 that provides mechanical protection to the injector head assembly 102, a service platform 106 that allows the operators to perform service on the coil tube injector 100 and manage the operation of the coil tube injector 100 during service, and a gooseneck 108 that controls the feed of the coil tubing 1 10 into the injector head assembly 102 from an external coil tube spool (not shown).
• a spool (not shown) may be disposed near the coil tube injector 100 and a coil tubing 1 10 may be drawn from the spool and directed over the gooseneck 108, and through the injector head assembly 102, into the wellbore.
• FIGS 2A-C depict different perspectives of a close up view of the injector head assembly 102 of Figure 1, in accordance with an illustrative embodiment of the present disclosure.
• the injector head assembly 102 may include a pair of gearbox units 202A, 202B, each coupled to a corresponding gripper/chain assembly 204A, 204B, respectively.
• the gearbox units 202A, 202B may be a hydraulic drive gearbox unit. Accordingly, each gripper/chain assembly 204A, 204B may be driven by the corresponding gearbox unit 202A, 202B.
• the injector head assembly 102 may further include one or more traction cylinders 206 that operate to apply pressure to skid plates 208.
• Figure 3 A depicts a side close-up view of the injector head assembly 102 of Figures 1 and Figures 2A-2C.
• Figure 3B depicts a cross-sectional view of the injector head assembly 102 of Figure 3 A.
• Figure 3C depicts a cross-sectional view of the injector head assembly of Figure 3 A with one side of the crash frame 104 removed to show the components as they are configured therein.
• each skid plate 208 is coupled to a bearing plate 212.
• the skid plates 208 and the bearing plates 212 may be made from any suitable material known to those of ordinary skill in the art.
• the skid plates 208 may be made from high grade aluminum and the bearing plates 212 may be made from hardened steel.
• the bearing plates 212 provide the wearing surface that is in contact with the roller bearings of the gripper/chain assembly 204, as discussed in more detail below.
• Figure 4 depicts a close-up view of one of a chain link of a gripper/chain assembly 204A, 204B which is denoted generally with reference numeral 400.
• the chain link 400 may consist of a roller bearing 402 on one side and a gripper 404 on the other side. As shown in Figure 4, the roller bearing 402 may be disposed on the side opposite to the gripper 404.
• Each gripper/chain assembly 204A, 204B may have a plurality of chain links 400 each having one or more roller bearings 402 and one or more grippers 404 as shown in Figure 4.
• the grippers 404 are configured to engage a length of coil tubing running through the injector head assembly 102.
• each gripper 404 may be configured as a semi-cylinder shaped cut-out allowing the surface of the gripper 404 to engage a greater area of the coil tubing 110 and more evenly apply pressure to the coil tubing ] 1 0.
• the cut-out for a gripper 404 may be sized differently to engage with different sizes of coil tubing 1 10.
• the gripper 404 may be coupled to roller bearings 402, which in turn engage a bearing plate 212.
• roller bearings 402 serves to reduce friction between the gripper/chain assembly 204 A, 204B and the corresponding bearing plate 212 by allowing the roller bearings 402 to roll across the surface of the bearing plate 212.
• Multiple links in the gripper/chain assembly 204 may be coupled through chain links 400. This arrangement permits an operator to replace/repair either one gripper 404 at a time or to replace/repair the entire gripper/chain assembly 204A, 204B in one service operation.
• Replacing the entire gripper/chain assembly 204A, 204B in one operation ensures that all grippers 404 operate in a similar condition, i.e., a singular worn item does not get maintained with the system. This also allows service to be performed in a shorter amount of time.
• the bearing plates 212 which are coupled to corresponding skid plates 208 provide a wearing surface for rollers 402 on the gripper/chain assembly 204.
• the traction cylinders 206 provide the force to push and pull the skid plate 208 so as to engage the bearing plate 212 with the gripper/chain assembly 204. Accordingly, the traction cylinders 206 can move the skid plates 208, and in turn, the bearing plates 212, between different positions to apply more, or less pressure, on to the coil tubing 1 10.
• the traction cylinders 206 may move the skid plates 208 and the bearing plates 212 between a first position which is further from the coil tubing 1 10 being directed through the injector head assembly 102 and a second position which is closer to the coil tubing 1 10. Accordingly, this configuration of the bearing plates 212 provides for reduced friction under load and provides a means of controlling the pressure on each gripper 404 as it is engaged within the load cycle via the skid plate 208 and traction cylinders 206.
• Figure 3B provides an illustration of the injector head assembly 102 focusing on the interaction of the skid plate 208, the bearing plate 212, and each gripper/chain assembly 204A and 204B.
• the operation of the injector head assembly 102 is now discussed in conjunction with one of the gripper/chain assemblies 204A.
• the other gripper/chain assembly 204B operates in the same manner.
• traction cylinders 206 apply pressure to the skid plate 208, which in turn applies pressure to the bearing plate 212.
• This brings the bearing plate 212 into contact with the gripper/chain assembly 204A, enabling the roller bearings 402 of the gripper/chain assembly 204A to roll across the surface of the bearing plate 212.
• the pressure to the bearing plate 212 engages the grippers 404 of the gripper/chain assembly 204A with a length of coil tubing that is being directed between the two gripper chain assemblies 204 A and 204B.
• FIG 3C is an illustration of an injector head assembly 102 focusing on the motion of each gripper/chain assembly 204A, 204B and the corresponding hydraulic drive gearbox unit 202A, 202B.
• each gripper/chain assembly 204A, 204B is coupled to a corresponding drive motor 205A, 205B which is driven by the gear box unit 202A, 202B.
• the drive motors 205 A, 205B provide a counter rotation arrangement to direct the coil tubing 1 10 into the well (or to pull the coil tubing 110 out).
• the drive motors 205 A, 205B are configured to turn in opposite directions such that the two facing sides of the two gripper/chain assemblies 204A, 204B move in the same vertical direction, i.e., move up together or move down together.
• one or more grippers 404 from each gripper/chain assembly 204A, 204B is able to engage with a length of coil tubing 1 10 running between the two facing sides of the two gripper/chain assemblies 204A, 204B.
• the traction cylinders 206 are pressured, moving the skid plates 208 towards the centrally located coil tubing 1 10 as it is passing through the gripper/chain assemblies 204 A, 204B. Once the gripper/chain assemblies 204A, 204B engage with the coil tubing 1 10, a reaction force is applied back through the bearing plates 212 and the skid plates 208, thereby allowing a precise control of the position and load being applied to the coil tubing 1 10.
• This arrangement is replicated about the vertical centerline of the injector head assembly 102, allowing the gripper/chain assemblies 204A, 204B to encapsulate the coil tubing 110 and move the coil tubing 1 10 up or down as directed by the drive motors 205A, 205B. Accordingly, the traction cylinders 206 apply pressure to the skid plates 208, to bring the bearing plates 212 into contact with the gripper/chain assembly 204A, 204B so as to engage a coil tube 1 10.
• the skid plate 208 which may be manufactured from high grade aluminum, may be guided via slides which are disposed on the skid plate 208. In certain implementations, there may be four slides, one located at each corner of the skid plate 208.
• Composite bearings may be used to ensure that the skid plate 208 slides smoothly on the guides.
• the traction cylinders 206 provide the force to push and pull the skid plate 208.
• the skid plate 208 is of a robust design to minimize the amount of deflection it will experience under the load condition. Minimizing the distortion ensures that the bearing plate 212 provides a smooth and level surface on which the roller bearings 402 of the gripper/chain assembly 204 can run.
• the injector head assembly 102 may further include one or more tensioning cylinders 210.
• the tensioning cylinders 210 may be disposed to apply a force in a direction that is substantially perpendicular to the direction of the force applied by the traction cylinders 206.
• the tensioning cylinders 210 are configured to apply sufficient force to ensure there is no chain 'slap' during operation.
• the tensioning cylinders 210 are operable to maintain a desired degree of tension within the chain/gripper assembly 204.
• the amount of force (pressure) applied to the traction cylinders 206 is proportional to the amount of grip force that will be exerted to the coil tubing 1 10.
• the traction cylinders 206 and the tensioning cylinders 210 are located or accessible from the outside of the injector head assembly 102.
• the traction cylinders 206 and the tensioning cylinders 210 may be mounted to an outer side of the crash frame 104. Accordingly, a single cylinder (either traction cylinder 206 and/or tension cylinder 210) may be removed and disengaged from the skid plate 208 to allow for replacement and/or repair of the cylinder. The remaining cylinders will continue to operate. As a result, the operable items may be repaired/replaced insitu and the injector head assembly 102 can remain in position above the well while it is being serviced. Additionally, in a preferred embodiment, the cylinders may all be of the same specification, simplifying the replacement of any cylinder during maintenance.
• the use of the roller bearings 402 which run against the bearing plate 212 under the load condition reduces the friction when operating under a load.
• the interaction of the bearing plates 212 with the roller bearings 402 of the gripper/chain assembly 204 provides a means of controlling the pressure applied by each gripper/chain assembly 204A, 204B as it engages the coil tubing 1 10.
• the applied pressure by each gripper/chain assembly 204 in a load cycle may be controlled by an operator using the traction cylinders 206 which apply pressure to the roller bearings 402 through the skid plates 208 and the bearing plates 212.
• the bearing plates 212 are sacrificial items given the arduous nature of coil tubing.
• the bearing plates 212 may be accessed from the front and rear of the injector head assembly 102 and they may be easily removed to the sides of the injector head assembly. Accordingly, the bearing plates 212 may be easily replaced and/or repaired in situ.
• the gripper/chain assemblies 204A, 204B are highly loaded during service. Accordingly, in certain implementations, the vertical space may be maximized to allow additional gripper assemblies to be in the load path, thus reducing the load to individual grippers 404, which in turn extends the life of the injector head assembly 102. Further, the grippers 404 are an integral part of the gripper/chain assembly 204. Accordingly, in certain implementations, a gripper carrier allows individual replacement of grippers 404. In another embodiment, the whole gripper/chain assembly 204 may be replaced in one operation.
• different components may be manufactured from high grade aluminum which is sufficiently strong while giving a reduced weight compared to steel (steel being roughly 2 1 ⁇ 2 times the weight of aluminum).
• the benefit of reduced weight is the ease of handling during installation, making the operator's job easier and therefore more productive.

Landscapes

• Engineering & Computer Science (AREA)
• Geology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Mining & Mineral Resources (AREA)
• Physics & Mathematics (AREA)
• Environmental & Geological Engineering (AREA)
• Fluid Mechanics (AREA)
• Mechanical Engineering (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Automatic Assembly (AREA)
• Spray Control Apparatus (AREA)
• Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
• Earth Drilling (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=51685982

Family Applications (1)

Country Status (8)

Families Citing this family (4)

Family Cites Families (10)

• 2014
  • 2014-04-10 US US14/250,156 patent/US20140305632A1/en not_active Abandoned
  • 2014-04-11 BR BR112015025168A patent/BR112015025168A2/pt not_active IP Right Cessation
  • 2014-04-11 EP EP14783502.9A patent/EP2984276A1/de not_active Withdrawn
  • 2014-04-11 AU AU2014250847A patent/AU2014250847A1/en not_active Abandoned
  • 2014-04-11 WO PCT/US2014/033746 patent/WO2014169178A1/en active Application Filing
  • 2014-04-11 CA CA2906981A patent/CA2906981A1/en not_active Abandoned
  • 2014-04-11 MX MX2015014243A patent/MX2015014243A/es unknown
  • 2014-04-11 CN CN201480018678.0A patent/CN105531441A/zh active Pending

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events