CN210049832U - Diamond drill bit with rear water spray hole - Google Patents
Diamond drill bit with rear water spray hole Download PDFInfo
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- CN210049832U CN210049832U CN201920591017.7U CN201920591017U CN210049832U CN 210049832 U CN210049832 U CN 210049832U CN 201920591017 U CN201920591017 U CN 201920591017U CN 210049832 U CN210049832 U CN 210049832U
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Abstract
The utility model relates to an oil and gas, mine engineering, geothermal well, construction foundation engineering construction, geology, hydrographic probing technical field, in particular to back water jet hole diamond bit. The device is characterized in that a rear water spraying hole seat extending from a drill bit body or connected to the drill bit body is arranged in front of at least one blade, a rear water spraying hole communicated with an inner flow channel of the drill bit is arranged on the rear water spraying hole seat, and the rear water spraying hole can be directly sprayed to cutting teeth on the blade or rocks in front of the cutting teeth. The utility model discloses a in high temperature drilling to the cutting tooth cooling abundant, the detritus migration in time, improve the drill bit drilling performance greatly.
Description
The technical field is as follows:
the utility model relates to an oil and gas, mine engineering, geothermal well, construction foundation engineering construction, geology, hydrographic probing technical field, in particular to back water jet hole diamond bit.
Background art:
drill bits are rock breaking tools used in drilling operations to break rock and form wellbores. Besides the cutting structure, the hydraulic structure on the drill bit plays an important role in the rock breaking efficiency and the service life of the drill bit, namely, cooling the cutting teeth, cleaning the well bottom, transporting rock debris, assisting in rock breaking and the like. At present, the hydraulic structure on the drill bit is designed by arranging nozzles or water holes at different positions on a drill bit body, and drilling fluid or cooling medium in an inner flow passage is sprayed out through the nozzles or the water holes so as to achieve the purposes of cooling cutting elements of the drill bit and cleaning a well bottom to discharge rock debris.
In modern fast drilling technology, the drill bit is required to have excellent rock breaking and cutting structures and good hydraulic performances of well bottom cleaning, rock debris migration, cutting tooth cooling and cleaning and the like. The hydraulic structure of the conventional drill bit can be designed only aiming at specific stratum, and firstly, the design of the corresponding drill bit is carried out aiming at soft stratum to prevent the drill bit from being mud-filled due to excessive rock debris in the drilling of the soft stratum; secondly, the design of a corresponding drill bit is carried out aiming at the hard stratum to prevent the cutting teeth from generating larger heat due to overlarge friction in the drilling process of the hard stratum, so that the cutting teeth cannot be cooled in time to generate the thermal wear phenomenon. The drill bit can only drill for soft stratum or hard stratum and other single stratum, but cannot drill for both soft and hard stratum. When the distance between the nozzle and the cutting tooth is larger, namely the spraying distance is large, the rock debris cannot be cleaned and moved in time when drilling into a soft stratum, so that the rock debris is continuously accumulated, a bit mud pocket is generated, and finally the bit fails; when drilling into hard stratum, the cutting teeth can not be cooled sufficiently in time due to friction, and the cutting teeth can be worn thermally. Particularly, in recent years, the temperature of the working environment of the drill bit is as high as 150 degrees or higher, the phenomenon of thermal wear of cutting teeth is greatly improved, and the service life and the drilling performance of the drill bit are obviously reduced.
With the continuous development of drilling, in order to make a diamond bit, particularly a PDC bit, have better working performance in difficult-to-drill strata (including hard strata, highly abrasive strata, strong heterogeneous strata, easily-balling strata and high-temperature strata), the scientificity of the hydraulic structure design of the bit must be improved, the cooling effect, the rock carrying effect and the rock breaking assisting effect of the bit are improved, and particularly, the thermal abrasion phenomenon of cutting teeth is reduced or even avoided as much as possible.
The utility model has the following contents:
the to-be-solved technical problem of the utility model is to provide a back water spray hole diamond bit, the device has realized in high temperature drilling that the cooling is abundant to the cutting tooth, the detritus migration in time, improves the drill bit drilling performance greatly. The defects that the conventional drill bit is not sufficiently cooled in high-temperature drilling and rock debris is not transferred in time, so that the drilling performance of the drill bit is reduced are overcome.
The utility model adopts the technical proposal that: the utility model provides a back water spray hole diamond bit, includes the drill bit body, extends the wing of self-drilling body, the wing includes leading flank and trailing flank, still be provided with the diamond cutter on the wing, it is adjacent form the water channel groove between the wing, at least one the place ahead of wing is provided with and extends from the drill bit body or connects the back water spray hole seat on the drill bit, be provided with on the back water spray hole seat with the communicating back water spray hole of drill bit inner flow way, back water spray hole can direct spray to the rock in cutting teeth or cutting teeth the place ahead on the wing.
Alternatively, at least one blade is used as a rear water spray hole seat, and a rear water spray hole is formed in the blade body.
Optionally, at least one blade is used as a rear water spraying hole seat, the rear water spraying hole is formed in the blade body, a protruding water hole body is arranged on the blade, and an outlet of the rear water spraying hole is formed in the protruding water hole body.
Alternatively, the outlet shape of the rear water spray hole arranged on the rear water spray hole seat comprises a circle, an ellipse, a rectangle, a flat and long shape or a combination of the circle, the ellipse, the rectangle and the flat and long shape.
Alternatively, the replaceable nozzle is arranged on the rear water spraying hole seat.
Alternatively, the injection position of at least 1 rear water injection hole at the bottom of the well is a cutting area of a rear blade cutting tooth.
Alternatively, at least 1 of the rear water jet holes is provided on the bottom of the well in front of the rear blade cutting teeth at the injection position at the bottom of the well and in the middle and/or front region of the water channel width of the water channel.
Alternatively, at least 1 of the rear water injection holes is provided on the bottom of the well in front of the rear blade cutting teeth at the injection position at the bottom of the well and in the middle and/or rear region of the water channel width of the water channel.
Alternatively, the spray angle range of at least 1 of the rear spray holes is 10 DEG or more and 70 DEG or less.
Alternatively, the spray angle range of at least 1 of the rear spray holes is 10 DEG or more and 45 DEG or less.
Optionally, the outlet of the rear water spray hole arranged on the rear water spray hole seat is a vertical non-circular water hole comprising an oval shape, a rectangular shape and a flat and long shape.
The utility model has the advantages that:
1. the drill bit is provided with the rear water spraying holes, so that the spraying distance of the water holes is obviously shortened, the energy dissipation is small, the spraying and dispersing phenomenon of a cooling medium can be effectively reduced, the hydraulic energy concentration is strong, the cooling of cutting teeth and the cleaning and the migration of well bottom rock debris are favorably improved, and the rock breaking performance of the drill bit is improved.
2. According to the invention, the rear water spray holes are arranged on the blades of the drill bit, so that the utilization efficiency of the structural space of the drill bit body can be improved, and the phenomenon that the tooth distribution space of the drill bit is reduced even avoided due to the arrangement of the rear water spray hole seats.
3. The rear water spray hole is easy to realize a smaller water spray hole spray angle, the smaller water spray hole spray angle is favorable for forming a wider circumferential or tangential jet flow coverage area on one hand and improving the cooling effect, and on the other hand, the smaller water spray hole spray angle is favorable for increasing the tangential scouring of the rock at the bottom of the well and flushing the broken and partially broken (cracked or partially broken) rock at the bottom of the well away from the bottom of the well, thereby achieving a better auxiliary rock breaking effect.
4. When setting up horizontal non-circular water hole in the water channel groove, can form wideer radial coverage area, do benefit to the balanced cooling of each cutting tooth, reinforcing chip removal ability weakens cutting element's thermal wear, and then improves sustainable, the efficient ability of creeping into of drill bit.
5. When vertical non-circular water holes are arranged in the water channel groove, a wider circumferential or tangential coverage area can be formed, the cooling of the rock at the bottom of the well is favorably strengthened, the working temperature of the cutting teeth is favorably reduced, and the drilling capability of the drill bit under the high-temperature condition is improved.
Description of the drawings:
the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Fig. 1 is a schematic structural diagram of a drill according to an embodiment of the present invention.
Fig. 2 is a schematic structural view of the utility model, in which the blade is arranged on the blade body or the water hole seat as the rear water spraying hole seat and the rear water spraying hole.
FIG. 3 is a schematic view of a drill bit with a circular water hole and a flat and long water hole at the outlet of the water hole on the rear water spray hole seat.
Fig. 4 is an isometric view of fig. 3.
Fig. 5 is a front view of fig. 3.
Fig. 6 is a cross-sectional view of fig. 3.
FIG. 7 is a schematic view showing the definition of the oblong water hole.
Fig. 8 is a schematic view of the replaceable nozzle installed on the rear water spray hole seat.
FIG. 9 is a schematic view of the cutting area of the jet cutting teeth of the rear water jet holes.
FIG. 10 is a schematic view of the post-orifice jet downhole rock.
FIG. 11 is a schematic view of a rear water spray hole seat with a vertical non-circular water hole.
Corresponding part names are labeled in the drawings: 1-a bit body; 101-an inner flow passage; 2-a blade; 21-a cutting tooth; 201-water hole on back side of blade; 202-wing nose; 203-blade back side; 3-a runner groove; 31-water holes in the flow channel; 4-rear water spraying hole seat; 41-end surface of rear water spraying hole seat; 411-circular water hole on the rear water spray hole seat; 412-horizontal flat long water holes on the rear water spray hole seat; 413-a detachable nozzle on the rear water spray hole seat; 414-vertical flat long water holes on the rear water spray hole seat; 42-a raised water hole body on the blade; 5-downhole rock.
The specific implementation mode is as follows:
to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the drawings of the embodiments of the present invention are combined to clearly and completely describe the technical solutions of the embodiments of the present invention, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention.
Cutting area of the cutting tooth: during downhole cutting, the rock is deformed and thus crushed by the cutting action of the tooth or cutting tooth, and this region includes the cutting edge of the cutting tooth and the rock in the range of 1.5 times the diameter of the cutting tooth in front of it.
Evenly dividing a well bottom rock area corresponding to a water channel between two adjacent blades into three parts according to the circumferential direction: proximal (I-zone), middle (II-zone) and distal (III-zone) teeth zones, see fig. 9.
For non-circular water holes (rectangular water holes, elliptical water holes, flat long water holes and the like, see fig. 7) with unequal outlet length d2 and width d1, if the length direction of the outlet is parallel or basically parallel to the bottom cutting contour line, the water holes are called horizontal water holes; the vertical water hole refers to the condition that the length direction of the outlet is vertical to the horizontal water hole, namely the length direction of the outlet is vertical or basically vertical to the cutting contour line of the bottom of the well.
Examples
A kind of diamond bit of back water spray hole, as shown in fig. 1, including bit body 1, blade 2 extending from bit body, the blade 2 includes blade leading flank 202 and blade trailing flank 203, still there are diamond cutting teeth 21 or cutting elements on the blade 2, adjacent form the water channel 3 between the blades, characterized by that: a rear water spraying hole seat 4 extending from the drill bit body or connected to the drill bit body 1 is arranged in front of at least one blade 2, and a rear water spraying hole communicated with the drill bit inner flow channel 101 is arranged on the end surface 41 of the rear water spraying hole seat 4. Namely, in the rotating direction of the drill bit, a water hole seat is arranged in front of at least one blade, a water hole capable of being sprayed backwards is arranged on the water hole seat, and the rear water hole can be directly sprayed to the cutting teeth on the blade or the rock in front of the cutting teeth.
In general, one blade has a front side surface at the front side in the direction of rotation of the drill and a rear side surface at the rear side, and as shown in fig. 1, reference numeral 202 denotes a blade front side surface and reference numeral 203 denotes a blade rear side surface.
The utility model discloses in, the distance of cutting teeth on the wing can be shortened with next-door neighbour and rotation to the setting of back water spray hole seat, and the liquid stream energy consumption is little, and jet velocity is big, has very big improvement to the cooling of cutting teeth and the migration ability of detritus. As will be readily appreciated by those skilled in the art, the rear spray orifice seat may also be provided with cutting teeth, as shown in fig. 2.
As a preferable example, at least one blade is used as a rear water spray hole seat, and a rear water spray hole is provided in the blade body, as shown in fig. 2. The scheme can improve the design flexibility of the hydraulic system of the drill bit aiming at different stratum conditions.
In the scheme, the utilization efficiency of the structural space of the bit body is improved, and the phenomenon that the tooth distribution space of the drill bit is reduced due to the arrangement of the water hole seat is reduced or even avoided.
As a preferable example, at least one blade is used as a rear water spray hole seat, a rear water spray hole is arranged on the blade body, a raised water spray hole body is arranged on the blade, and a rear water spray hole outlet is arranged on the raised water spray hole body, as shown in fig. 1 and 2. The scheme can shorten the jet distance of liquid flow to the cutting teeth or rocks, improve the jet speed and reduce the waste of hydraulic energy. Meanwhile, the influence on the cutting structure of the blade wing can be reduced by arranging the protruding water hole body.
As a preferable example, the outlet shape of the rear water spray hole provided on the rear water spray hole seat includes a circle, a semicircle, an ellipse, a rectangle, a rhombus, a flat long shape or a combination thereof, as shown in fig. 3, 4 and 5, the water hole on the water spray hole seat is a combination of a circle water hole and a flat long water hole. For easy understanding of the oblong water hole, referring to fig. 7, d1 is the oblong water hole outlet width, and d2 is the oblong water hole outlet length; here, the convention that the value of d2/d1 is greater than 1 means that the water hole is oblong. Obviously, when the water hole is irregular in the width direction and the length direction, the width is the maximum width and the length is the maximum length. The different water hole outlet shapes of this scheme can be selected to different stratum conditions and cooling zone, rationally optimizes hydraulic energy's utilization ratio to improve the cooling effect of stratum rock and cutting teeth greatly, improve well drilling efficiency.
As a preferred example, the replaceable nozzle is installed on the rear water spray hole seat, as shown in fig. 8. The scheme can timely replace the damage phenomenon of the nozzle caused in the liquid flow jetting process, thereby improving the utilization rate of the hydraulic energy of the drill bit and improving the cooling energy of the rock or the cutting teeth at the bottom of the well. In addition, different water hole parameter combinations are often required under different application conditions, and the replaceable nozzle is favorable for improving the adaptability of the drill bit to the use conditions.
Preferably, the injection position of at least 1 rear water injection hole at the bottom of the well is a cutting area of a rear blade cutting tooth, as shown in an area I in fig. 9 and fig. 10. The scheme can reduce the surface temperature of a bottom cutting area, effectively relieve cutting heat generated by cutting teeth in the cutting process and improve the cutting efficiency.
Preferably, at least 1 of the rear water jet holes is provided on the bottom rock in front of the rear blade cutting teeth at the bottom hole injection position, and in the middle and/or front region of the channel width of the channel, such as region II in fig. 9. The scheme can cool the rock in the area in advance, so that when the cutting teeth cut the part of the rock, the friction heat between the process action and the cutting teeth is reduced, and the cutting efficiency of the cutting teeth is improved.
Preferably, at least 1 of the rear water jet holes is provided on the bottom of the well in front of the rear blade cutting teeth at the bottom of the well and in the middle and/or rear region of the width of the channel, as shown in the middle III region of fig. 9. This solution allows an efficient cooling of the area in advance. Particularly in high-temperature drilling, under the combined action of underground high temperature and cutting heat, the temperature of a cutting area is extremely high, the area to be cut is cooled in advance, and cutting cooling is carried out on a cutting tooth to be cut, so that the increase of the cutting heat generated in the area to be cut and the cutting area in the process is avoided, and the thermal abrasion phenomenon is effectively avoided.
As a preferable example, the injection angle range of at least 1 rear water injection hole at the bottom of the well is 10 degrees to 70 degrees, and the injection angle a of the rear water injection hole at the bottom of the well is the included angle between the jet axis or the central line and the rock surface at the bottom of the well, as shown in figure 10. The scheme can realize the cooling range of the water holes to different areas, so that the cooling area required is effectively cooled in a targeted manner, especially when the temperature of the cutting part in high-temperature drilling is higher, the service life of the cutting teeth is prolonged by cooling the area through the water holes, the thermal wear phenomenon is reduced, and the drilling efficiency is improved.
As a preferable example, the outlet of the rear water spray hole provided on the rear water spray hole seat is a vertical non-circular water hole including an oval shape, a rectangular shape, a diamond shape, and a flat and long shape, and as shown in fig. 11, is a flat and long vertical water hole. The scheme increases the circumferential or tangential sweeping range or the coverage range of the water holes to the bottom hole rocks, and is beneficial to improving the cooling effect of jet flow to the bottom hole rocks and the cutting teeth.
Preferably, the cutting elements or cutting elements of the diamond bit are PDC (polycrystalline diamond compact) elements, or diamond impregnated cutting elements, or a combination of various cutting elements to accommodate the requirements of different formation conditions in the borehole.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (11)
1. The utility model provides a back water spray hole diamond bit, includes the drill bit body, extends from the wing of drill bit body, the wing includes leading flank and trailing flank, still be provided with the diamond cutter on the wing, it is adjacent form the water channel groove between the wing, its characterized in that: and a rear water spraying hole seat extending from the drill bit body or connected to the drill bit body is arranged in front of at least one blade, a rear water spraying hole communicated with the inner flow channel of the drill bit is arranged on the rear water spraying hole seat, and the rear water spraying hole can be directly sprayed to the cutting teeth on the blade or the rock in front of the cutting teeth.
2. The post-orifice diamond drill bit according to claim 1, wherein: at least one blade is used as a rear water spraying hole seat, and a rear water spraying hole is formed in the blade body.
3. The post-orifice diamond drill bit according to claim 1, wherein: regard as back water spray hole seat at least one wing, back water spray hole sets up on the wing body, just have protruding water hole body on the wing, back water spray hole export sets up protruding water hole body on.
4. The post-orifice diamond drill bit according to claim 1, wherein: the outlet shape of the rear water spray hole arranged on the rear water spray hole seat comprises a round shape, an oval shape, a rectangular shape, a flat-long shape or a combination of the round shape, the oval shape, the rectangular shape and the flat-long shape.
5. The post-orifice diamond drill bit according to claim 1, wherein: the replaceable nozzle is arranged on the rear water spray hole seat.
6. The post-orifice diamond drill bit according to claim 1, wherein: and the spraying position of at least 1 rear water spraying hole at the bottom of the well is a cutting area of the rear blade cutting teeth.
7. The post-orifice diamond drill bit according to claim 1, wherein: and the spraying position of at least 1 rear water spraying hole at the bottom of the well is on the rock at the bottom of the well in front of the cutting teeth of the rear blade, and is in the middle and/or front area of the width of the water channel groove.
8. The post-orifice diamond drill bit according to claim 1, wherein: and the spraying position of at least 1 rear water spraying hole at the bottom of the well is on the rock at the bottom of the well in front of the cutting teeth of the rear blade, and is in the middle and/or rear area of the width of the water channel groove.
9. The post-orifice diamond drill bit according to claim 1, wherein: the spraying angle range of at least 1 rear spraying hole is more than or equal to 10 degrees and less than or equal to 70 degrees.
10. The post-orifice diamond drill bit according to claim 1, wherein: the spraying angle range of at least 1 rear spraying hole is more than or equal to 10 degrees and less than or equal to 45 degrees.
11. The post-orifice diamond drill bit according to claim 1, wherein: the outlet of the rear water spray hole arranged on the rear water spray hole seat is a vertical non-circular water hole comprising an oval shape, a rectangular shape and a flat and long shape.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920591017.7U CN210049832U (en) | 2019-04-28 | 2019-04-28 | Diamond drill bit with rear water spray hole |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920591017.7U CN210049832U (en) | 2019-04-28 | 2019-04-28 | Diamond drill bit with rear water spray hole |
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| Publication Number | Publication Date |
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| CN210049832U true CN210049832U (en) | 2020-02-11 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920591017.7U Active CN210049832U (en) | 2019-04-28 | 2019-04-28 | Diamond drill bit with rear water spray hole |
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| CN (1) | CN210049832U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110107227A (en) * | 2019-04-28 | 2019-08-09 | 中国石油集团长城钻探工程有限公司 | A kind of diamond bit with efficient outlet hole structure |
| CN112145086A (en) * | 2020-09-28 | 2020-12-29 | 沧州格锐特钻头有限公司 | Drill bit with auxiliary drilling function |
| CN114645676A (en) * | 2022-04-02 | 2022-06-21 | 西南石油大学 | PDC drill bit with adjustable nozzle on blade |
-
2019
- 2019-04-28 CN CN201920591017.7U patent/CN210049832U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110107227A (en) * | 2019-04-28 | 2019-08-09 | 中国石油集团长城钻探工程有限公司 | A kind of diamond bit with efficient outlet hole structure |
| CN112145086A (en) * | 2020-09-28 | 2020-12-29 | 沧州格锐特钻头有限公司 | Drill bit with auxiliary drilling function |
| CN112145086B (en) * | 2020-09-28 | 2023-02-03 | 沧州格锐特钻头有限公司 | Drill bit with auxiliary drilling function |
| CN114645676A (en) * | 2022-04-02 | 2022-06-21 | 西南石油大学 | PDC drill bit with adjustable nozzle on blade |
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Effective date of registration: 20201026 Address after: 100120 Beijing Xicheng District six laying Kang Patentee after: CHINA NATIONAL PETROLEUM Corp. Patentee after: China National Petroleum Corporation Great Wall Drilling Engineering Co.,Ltd. Address before: 124010 Xinglongtai, Liaoning Province, oil street, No. 96, No. Patentee before: China National Petroleum Corporation Great Wall Drilling Engineering Co.,Ltd. |