阅读说明：本技术 井下防卡滑装置 (Underground anti-skid device ) 是由 夏文安 牛洪波 杨春旭 曹继飞 刘晓兰 毕研涛 李文飞 于 2020-05-23 设计创作，主要内容包括：本发明公开的井下防卡滑装置安装在动力钻具与井下钻柱之间,当井眼有曲屈或者因地层原因发生托压现象,底部钻头空转,当继续加压钻进时,上部钻具突然释放,钻头瞬时重压吃入地层,PDC钻头发生卡滑导致动力马达制动失速,会造成马达憋压升高,钻具反扭矩增大,此时下腔室的压力大于上腔室压力,同时芯轴下部的扭转弹簧受到反扭力作用在芯轴上,这两种力同时克服上部钻具施加给芯轴的碟簧预紧力,使得上部碟簧压缩,把钻头瞬时提离井底,卡滑失速现象发生的初期就及时消除,保护了钻头和地面机泵的安全性,达到提高钻井破岩效率,降低钻井综合成本的目的。同时,井下防卡滑装置具有结构简单、操作方便、便于安装、安全可靠的优点。(The underground anti-skid device disclosed by the invention is arranged between a power drilling tool and an underground drill string, when a borehole bends or is subjected to pressure supporting phenomenon due to stratum, a bottom drill bit idles, when the pressurized drilling is continued, the upper drilling tool is suddenly released, the instantaneous heavy pressure of the drill bit is absorbed into the stratum, the PDC drill bit is blocked and slid to drive the force motor to brake and stall, the pressure of the motor is suppressed and increased, the reaction torque of the drilling tool is increased, the pressure of the lower cavity is higher than the pressure of the upper cavity, meanwhile, the torsion spring at the lower part of the mandrel is acted on the mandrel by the counter-torsion force, the two forces simultaneously overcome the disc spring pretightening force applied to the mandrel by the upper drilling tool, the upper disc spring is compressed, the drill bit is lifted away from the well bottom instantly, the initial stage of the slip stall phenomenon is eliminated in time, the safety of the drill bit and a ground pump is protected, and the purposes of improving the drilling and rock breaking efficiency and reducing the comprehensive drilling cost are achieved. Meanwhile, the underground anti-blocking and anti-sliding device has the advantages of simple structure, convenience in operation and installation, safety and reliability.)

1. The underground anti-skid device is characterized by comprising an outer shell (5), a mandrel (7), a spring (8), a torsion spring (13) and a lower end cover (15); wherein:

an upper connector is arranged at the upper part of the outer shell (5), the lower end of the outer shell is in plugging connection and matching with a lower end cover (15), an annular bulge is arranged on the inner wall of the middle section to form an upper annular groove and a lower annular groove, an outer shell spline (11) is arranged on the inner wall of the annular bulge of the middle section, and a radial outer through hole (10) is arranged on the wall of the annular groove of the upper section;

the mandrel (7) is arranged in the outer shell (5), the outer wall is provided with three sections of annular bulges at intervals along the axial direction, the outer edges of the three sections of annular bulges are in axial sliding sealing fit with the inner wall of the outer shell (5), the two sections of annular bulges are arranged in an annular groove at the upper section of the outer shell (5) and are respectively arranged above and below the radial outer through hole (10), the annular bulges at the lower section are arranged in the annular groove at the lower section of the outer shell (5), a radial inner through hole (14) is arranged on the tube wall below the annular bulges at the lower section of the mandrel (7), the outer wall between the two sections of annular bulges at the middle section of the mandrel (7) is provided with a housing spline (11) arranged on the inner wall of the annular bulges at the middle section of the outer shell (5) to form axial sliding and circumferential limiting fit, and the lower end of the mandrel (7) is provided with a lower joint;

the spring (8) is arranged in the annular bulge at the upper section of the mandrel (7) and the annular groove at the upper section of the outer shell (5) and forms extrusion fit with the annular bulge at the upper section of the mandrel (7) and the annular groove at the upper section of the outer shell (5);

and the torsion spring (13) is arranged in the lower section annular bulge of the mandrel (7) and the lower section annular groove of the outer shell (5) and forms extrusion fit with the lower section annular bulge of the mandrel (7) and the lower section annular groove of the outer shell (5).

2. The downhole anti-seize device according to claim 1, wherein: the spring (8) is a disc spring.

3. A downhole anti-seize device according to claim 1 or 2, wherein: the contact position of the upper part of the mandrel (7) and the outer shell (5) is provided with a seal I (6), the contact position of the outer edge of the annular bulge of the mandrel (7) and the inner wall of the outer shell (5) is provided with a seal II (9), and a seal III (16) is arranged between the lower flange of the mandrel (7) and the lower end cover (15) of the outer shell (5).

4. The underground anti-skid device is characterized by comprising an outer shell (5), a mandrel (7), a spring (8), a torsion spring (13) and a lower end cover (15); wherein:

an upper connector is arranged at the upper part of the outer shell (5), the lower end of the outer shell is in plugging connection and matching with a lower end cover (15), an annular bulge is arranged on the inner wall of the middle section to form an upper annular groove and a lower annular groove, an outer shell spline (11) is arranged on the inner wall of the annular bulge of the middle section, and a radial outer through hole (10) is arranged on the wall of the annular groove of the upper section;

the mandrel (7) is arranged in the outer shell (5), the outer wall is provided with a middle section of annular bulge and a lower section of annular bulge at intervals along the axial direction, the outer edges of the two sections of annular bulges are in axial sliding sealing fit with the inner wall of the outer shell (5), the middle section of annular bulge is arranged in an upper section of annular groove of the outer shell (5) and is arranged below the radial outer through hole (10), the lower section of annular bulge is arranged in a lower section of annular groove of the outer shell (5), a radial inner through hole (14) is arranged on the pipe wall below the lower section of annular bulge of the mandrel (7), the outer wall between the middle section of annular bulge and the lower section of the mandrel (7) is provided with a housing spline (11) arranged on the inner wall of the middle section of annular bulge of the outer shell (5) to form axial sliding and circumferential limiting fit, and the lower joint is arranged at the lower end of the mandrel (7);

the spring (8) is arranged in the annular bulge at the middle section of the mandrel (7) and the annular groove at the upper section of the outer shell (5) and forms extrusion fit with the annular bulge at the middle section of the mandrel (7) and the annular groove at the upper section of the outer shell (5);

and the torsion spring (13) is arranged in the lower section annular bulge of the mandrel (7) and the lower section annular groove of the outer shell (5) and forms extrusion fit with the lower section annular bulge of the mandrel (7) and the lower section annular groove of the outer shell (5).

5. The downhole anti-seize device according to claim 1, wherein: the spring (8) is a disc spring.

6. A downhole anti-seize device according to claim 1 or 2, wherein: the contact position of the upper part of the mandrel (7) and the outer shell (5) is provided with a seal I (6), the contact position of the outer edge of the annular bulge of the mandrel (7) and the inner wall of the outer shell (5) is provided with a seal II (9), and a seal III (16) is arranged between the lower flange of the mandrel (7) and the lower end cover (15) of the outer shell (5).

Technical Field

The invention relates to an underground drilling tool in the field of petroleum drilling, in particular to an underground anti-skid device.

Background

In the process of petroleum and natural gas drilling, geological exploration and mine drilling, wells with complex structures such as deep wells, ultra-deep wells, highly deviated wells, extended reach wells and the like are increasingly widely applied, and higher requirements are put forward on the drilling process technology. In the drilling process, the PDC drill bit has the advantages of long service life and high drilling speed, so that the PDC drill bit is widely used.

The bottom drilling tool combination of the PDC + the power motor in the bottom drilling tools in the world drilling industry is a standard configuration of drilling, but the inherent rock breaking mechanism of a PDC drill bit determines that the instant slip stall phenomenon easily occurs when drilling various complex stratums, large-displacement directional wells and long-horizontal-section horizontal wells, so that the power motor is braked, particularly in the directional sliding drilling process of drilling large-displacement wells, horizontal wells, long-steady-slope directional wells and soft stratum well sections, the drilling tool does not rotate and only performs sliding drilling at the moment, the friction between the drilling tool and the well bore is greatly increased, the drilling tool in the upper well bore is easy to bend due to irregular and unsmooth well bore, the pressure supporting phenomenon of the drilling tool occurs in the well bore, meanwhile, the centralizers in the drilling tool and the power motor can also generate the pressure supporting phenomenon due to large friction resistance in the sliding drilling of the drilling tool, and the pressure supporting is instantaneously released in the continuous pressurizing process of a ground driller, the accumulated large drill bit is suddenly transferred to the PDC drill bit, the PDC drill bit is instantaneously subjected to overlarge drilling pressure and pressed into the stratum too deep, too much drilling is eaten, and the brakes cause the braking of a screw drilling tool, the ground pumping pressure is generated by the braking, the drilling work cannot be continued, the underground drilling tool, a ground pipeline, a pump and other equipment are greatly overloaded and damaged, and the service life of the PDC drill bit is greatly reduced, at present, a mode for responding by field operators is that only a ground slurry pump is turned off and then the drilling tool is lifted up, then a slurry pump is turned on and the drilling tool is moved up and down greatly until the well drilling tool is unblocked, but the slip stall phenomenon still frequently occurs in the slip drilling of the well track adjustment of a complicated structure well, a large amount of drilling time is occupied, even two thirds of the time is used for processing the slip phenomenon, and when the pumping pressure is instantaneously raised to the limit, the pump is often damaged seriously, and frequent repair of the pump takes a lot of time, greatly reduces the drilling speed, thereby causing the increase of the drilling cost and causing overload damage to drilling equipment.

Disclosure of Invention

The invention aims to reduce or eliminate the influence of the sliding and stalling of the PDC drill bit, improve the drilling speed, reduce the comprehensive construction cost and provide an underground anti-sliding device for reducing or eliminating the influence of the sliding and braking of the PDC drill bit on the sites of petroleum and natural gas drilling, geological exploration and mine drilling.

The technical scheme adopted by the invention for solving the technical problems is as follows:

an underground anti-skid device comprises an outer shell, a mandrel, a spring, a torsion spring and a lower end cover; wherein:

the upper part of the outer shell is provided with an upper connector, the lower end of the outer shell is in sealing connection and matching with the lower end cover, the inner wall of the middle section is provided with an annular bulge to form an upper annular groove and a lower annular groove, the inner wall of the annular bulge of the middle section is provided with an outer shell spline, and the wall of the annular groove of the upper section is provided with a radial outer through hole;

the mandrel is arranged in the outer shell, an upper section of annular bulge, a middle section of annular bulge and a lower section of annular bulge are axially arranged on the outer wall of the mandrel at intervals, the outer edges of the three sections of annular bulges are in axial sliding sealing fit with the inner wall of the outer shell, the upper section of annular bulge and the middle section of annular bulge are arranged in an annular groove on the upper section of the outer shell and are respectively arranged above and below a radial outer through hole, the lower section of annular bulge is arranged in an annular groove on the lower section of the outer shell, a radial inner through hole is arranged on the pipe wall below the lower section of annular bulge of the mandrel, an outer wall between the middle section of annular bulge and the lower section of annular bulge in the mandrel is provided with a spline of the outer shell arranged on the inner wall of the annular bulge on the middle section of the outer shell to form axial sliding and circumferential limiting fit, and a lower joint is arranged at the lower end of the mandrel;

the spring is arranged in the annular bulge at the upper section of the mandrel and the annular groove at the upper section of the outer shell and forms extrusion fit with the annular bulge at the upper section of the mandrel and the annular groove at the upper section of the outer shell;

the torsion spring is arranged in the annular bulge at the lower section of the mandrel and the annular groove at the lower section of the outer shell and forms extrusion fit with the annular bulge at the lower section of the mandrel and the annular groove at the lower section of the outer shell.

The other underground anti-skid device comprises an outer shell, a mandrel, a spring, a torsion spring and a lower end cover; wherein:

the upper part of the outer shell is provided with an upper connector, the lower end of the outer shell is in sealing connection and matching with the lower end cover, the inner wall of the middle section is provided with an annular bulge to form an upper annular groove and a lower annular groove, the inner wall of the annular bulge of the middle section is provided with an outer shell spline, and the wall of the annular groove of the upper section is provided with a radial outer through hole;

the mandrel is arranged in the outer shell, the outer wall of the mandrel is provided with a middle section of annular bulge and a lower section of annular bulge at intervals along the axial direction, the outer edges of the two sections of annular bulges are in axial sliding sealing fit with the inner wall of the outer shell, the middle section of annular bulge is arranged in an annular groove at the upper section of the outer shell and is arranged below a radial outer through hole, the lower section of annular bulge is arranged in an annular groove at the lower section of the outer shell, a radial inner through hole is arranged on the pipe wall below the lower section of annular bulge of the mandrel, the outer wall between the middle section of annular bulge and the lower section of the mandrel is provided with a housing spline which is arranged on the inner wall of the annular bulge at the middle section of the outer shell to form axial sliding and circumferential limiting fit, and the lower end of the mandrel is provided with a lower joint;

the spring is arranged in the annular bulge at the middle section of the mandrel and the annular groove at the upper section of the outer shell and forms extrusion fit with the annular bulge at the middle section of the mandrel and the annular groove at the upper section of the outer shell;

the torsion spring is arranged in the annular bulge at the lower section of the mandrel and the annular groove at the lower section of the outer shell and forms extrusion fit with the annular bulge at the lower section of the mandrel and the annular groove at the lower section of the outer shell.

The above scheme further comprises: the spring is a disc spring. The contact part of the upper part of the mandrel and the outer shell is provided with a seal I, the contact part of the outer edge of the annular bulge of the mandrel and the inner wall of the outer shell is provided with a seal II, and a seal III is arranged between the flange of the lower part of the mandrel and the lower end cover of the outer shell.

The underground anti-skid device is arranged between a power motor and a drill column, when the well is normally drilled, a mud power motor drives a PDC drill bit to drill in a rotating mode, instantaneous skid is easy to occur when the PDC drill bit drills various complex stratums in a sliding mode due to the inherent shearing and rock breaking mechanism of the PDC drill bit, and then the power motor is braked.

In the invention, during normal drilling, the torque of the rotary table is transmitted between the outer shell and the mandrel through the meshing of the internal spline and the external spline, the bit pressure is transmitted to the mandrel through the disc spring on the upper part of the compression mandrel and then applied to the drill bit, two chambers are arranged between the outer shell and the mandrel, when the PDC drill bit just eats into the stratum excessively, the jamming of the PDC drill bit can cause the pressure of the motor to rise, the reaction torque of the drilling tool is increased, the pressure of the lower chamber is larger than the pressure of the upper chamber, simultaneously, the torsion spring on the lower part of the mandrel is acted on the mandrel by the reaction torque, the two forces simultaneously overcome the spring force applied to the mandrel by the upper drilling tool, the upper disc spring is compressed, the drill bit is lifted away from the bottom of the well instantaneously, the large reaction torque on the mandrel and the high pressure of the lower chamber caused by braking stall are released, the phenomenon of the jamming stall of the drill bit is eliminated, once the drill bit is lifted, the fluid in the drilling tool recovers to the normal pressure when the reasonable shearing amount is reached, the pressure of the upper chamber and the lower chamber of the anti-skid tool reaches balance, and under the action of the bit pressure, the mandrel moves downwards to transfer the bit pressure to the drill bit and continue normal drilling. The phenomenon that drilling is stopped due to the generation of the slip stall is prevented, the phenomena of drill bit, ground pump, pipeline and overload are effectively prevented, the service lives of the drill bit, the ground pump and the pipeline are protected, and the purposes of improving the drilling construction efficiency and reducing the comprehensive drilling cost are achieved.

On the premise of meeting the drilling safety, the underground anti-skid device capable of reducing or eliminating the skid and braking of the PDC drill bit is arranged underground, the skid effect generated in the drilling process can be effectively reduced or eliminated, and the underground anti-skid device has great practical significance on the drilling speed of extended reach wells, horizontal wells, long and steady slope directional wells and wells with complex structures. Compared with the prior art, the invention has the beneficial effects that: effectively prevent drill bit, ground machine pump and pipeline and overload phenomenon, protect the life-span of drill bit, ground machine pump and pipeline, reach and improve well drilling efficiency of construction, reduce the well drilling comprehensive cost. Meanwhile, the tool also has the advantages of simple structure, convenience in installation, safety and reliability.

Drawings

Fig. 1 is a schematic view of the installation position of the downhole anti-skid device of the invention.

Fig. 2 is a structural sectional view of the downhole anti-stick device of the present invention in an operating position.

Fig. 3 is a partial oblique view at a in fig. 2.

In the figure: 1. the drill bit comprises an upper drill string, 2. a downhole anti-skid device, 3. a power motor, 4. a drill bit, 5. an outer shell, 6. a seal I, 7. a mandrel, 8. a spring, 9. a seal II, 10. an outer through hole, 11. an outer shell spline, 12. a mandrel spline, 13. a torsion spring, 14. a mandrel inner through hole, 15. a lower end cover, 16. a seal III, 17. an upper chamber and 18. a lower chamber.

Detailed Description

The invention is described in further detail below with reference to the figures and the detailed description.

Example 1

A downhole anti-skid device comprises an outer shell 5, a mandrel 7, a spring 8, a torsion spring 13 and a lower end cover 15; wherein:

an upper connector is arranged at the upper part of the outer shell 5, the lower end of the outer shell is in plugging connection and matching with a lower end cover 15, an annular bulge is arranged on the inner wall of the middle section to form an upper annular groove and a lower annular groove, an outer shell spline 11 is arranged on the inner wall of the annular bulge of the middle section, and a radial outer through hole 10 is arranged on the wall of the annular groove of the upper section;

the mandrel 7 is arranged in the outer shell 5, the outer wall is provided with three sections of annular bulges at intervals along the axial direction, the outer edges of the three sections of annular bulges are in axial sliding sealing fit with the inner wall of the outer shell 5, the two sections of annular bulges are arranged in an annular groove at the upper section of the outer shell 5 and are respectively arranged above and below the radial outer through hole 10, the lower section of annular bulge is arranged in the annular groove at the lower section of the outer shell 5, a radial inner through hole 14 is arranged on the pipe wall below the lower section of annular bulge of the mandrel 7, the outer wall between the two sections of annular bulges in the mandrel 7 and the outer shell spline 11 arranged on the inner wall of the annular bulge at the middle section of the outer shell 5 are in axial sliding and circumferential limiting fit, and the lower end of the mandrel 7 is provided with a lower joint;

the spring 8 is arranged in the annular bulge at the upper section of the mandrel 7 and the annular groove at the upper section of the outer shell 5, and forms extrusion fit with the annular bulge at the upper section of the mandrel 7 and the annular groove at the upper section of the outer shell 5;

the torsion spring 13 is arranged in the lower annular bulge of the mandrel 7 and the lower annular groove of the outer shell 5, and forms extrusion fit with the lower annular bulge of the mandrel 7 and the lower annular groove of the outer shell 5.

Example 2

A downhole anti-skid device comprises an outer shell 5, a mandrel 7, a spring 8, a torsion spring 13 and a lower end cover 15; wherein:

an upper connector is arranged at the upper part of the outer shell 5, the lower end of the outer shell is in plugging connection and matching with a lower end cover 15, an annular bulge is arranged on the inner wall of the middle section to form an upper annular groove and a lower annular groove, an outer shell spline 11 is arranged on the inner wall of the annular bulge of the middle section, and a radial outer through hole 10 is arranged on the wall of the annular groove of the upper section;

the mandrel 7 is arranged in the outer shell 5, the outer wall is provided with a middle section of annular bulge and a lower section of annular bulge at intervals along the axial direction, the outer edges of the two sections of annular bulges are in axial sliding sealing fit with the inner wall of the outer shell 5, the middle section of annular bulge is arranged in an upper section of annular groove of the outer shell 5 and is arranged below the radial outer through hole 10, the lower section of annular bulge is arranged in a lower section of annular groove of the outer shell 5, a radial inner through hole 14 is arranged on the tube wall below the lower section of annular bulge of the mandrel 7, the outer wall between the middle section of annular bulge and the lower section of annular bulge in the mandrel 7 forms axial sliding and circumferential limiting fit with an outer shell spline 11 arranged on the inner wall of the middle section of annular bulge of the outer shell 5, and the lower end of the mandrel 7 is provided with a lower joint;

the spring 8 is arranged in the annular bulge at the middle section of the mandrel 7 and the annular groove at the upper section of the outer shell 5, and forms extrusion fit with the annular bulge at the middle section of the mandrel 7 and the annular groove at the upper section of the outer shell 5;

the torsion spring 13 is arranged in the lower annular bulge of the mandrel 7 and the lower annular groove of the outer shell 5, and forms extrusion fit with the lower annular bulge of the mandrel 7 and the lower annular groove of the outer shell 5.

Example 3

On the basis of the embodiment 1 or 2, the method further comprises the following steps: the spring 8 is a disc spring. The contact part of the upper part of the mandrel 7 and the outer shell 5 is provided with a seal I6, the contact parts of the outer edge of the annular bulge of the mandrel 7 and the inner wall of the outer shell 5 are provided with a seal II 9, and a seal III 16 is arranged between the flange at the lower part of the mandrel 7 and the lower end cover 15 of the outer shell 5.

Example 4

Referring to figure 1 of the drawings, in actual operation, a downhole anti-stick device 2 is mounted intermediate an upper drill string 1 and a bottom power motor 3.

Referring to fig. 2, a mandrel 7 is installed in the outer shell 5, and a spring 8 is installed in a closed cavity formed by the upper flange of the mandrel 7 and the outer shell 1, wherein the spring 8 is a disc spring. The lower end cover 15 is arranged at the lower part of the outer shell 5, the torsion spring 13 is arranged in a closed cavity formed by the outer shell 5, the lower end cover 15 and the mandrel 7, and the torsion spring 13 is arranged between the flange of the mandrel 7 and the flange of the lower end cover 15. The outer shell 5 is internally provided with an outer shell spline 11, the mandrel 7 is provided with a mandrel spline 12, and the outer shell 5 is in spline fit with the mandrel 7 through the outer shell spline 11 and the mandrel spline 12.

An upper chamber 17 and a lower chamber 18 are arranged between the outer shell 5 and the mandrel 7, the flanges of the outer shell 5 and the upper chamber 17 form the upper chamber 17, and a radial outer through hole 10 is arranged on the upper pipe wall of the outer shell 5 corresponding to the upper chamber 17. The lower end cover 15, the outer shell 5 and the flange of the upper chamber 17 form a lower chamber 18, and a radial inner through hole 14 is formed in the lower pipe wall of the mandrel 7 corresponding to the lower chamber 18.

A seal I6 is arranged between the upper part of the mandrel 7 and the outer shell 5, a seal II 9 is arranged between the mandrel 7 and the outer shell 5 to divide an upper chamber 17 and a lower chamber 18, the seal II 9 is arranged at the contact part of the flange of the mandrel 7 and the outer shell 5, and a seal III 16 is arranged between the flange of the lower part of the mandrel 7 and the lower part of the outer shell 5.

Referring to figures 1 to 3 of the drawings, a downhole anti-stick device is mounted between a power motor 3 and an upper drill string 1. When the normal pump is started for drilling, the underground anti-skid device is equivalent to a common drilling tool short section, the outer shell 5 and the mandrel 7 are engaged with each other through the internal spline and the external spline to transmit the torque of the turntable, and the drilling pressure is transmitted to the mandrel 7 through the pre-pressing spring 8 on the upper part of the mandrel 7 and then applied to the drill bit 4 to realize the normal drilling work.

Under the normal condition, spring 8 sets for in advance the pretension pressure, when PDC drill bit 4 when the orbit adjustment of creeping into large displacement directional well, deep horizontal well, complex structure well, the drilling tool irrotational only carries out the slip and creeps into this moment, the frictional resistance greatly increased between drilling tool and the well bore, upper portion drilling string 1 in the well bore is because of the irregular unsmooth in well bore, very easy emergence flexure, centralizer on the power motor 3 in the drilling string of lower part also can produce the backing pressure simultaneously, cause the weight on the drilling can't transmit to drill bit 4, the idle running takes place for drill bit 4 this moment. As the upper bit pressure continues to increase, the rotary column instantaneously overcomes the frictional resistance between the rotary column and the borehole, and the large bit pressure accumulated by the upper drill string 1 is instantaneously transmitted to the PDC bit 4, so that the PDC bit 4 immediately bears more than normal shearing amount, and the PDC bit 4 bears larger torque. According to the principle that the acting force is equal to the reacting force, meanwhile, the PDC drill bit 4 can transmit the same larger reacting torque force to the mandrel 7, the acting force is further applied to the pre-compressed torque spring 13, the torque spring 13 is acted by the reacting torque force, meanwhile, the power motor 3 brakes the situation that the pressure of the lower cavity in the underground anti-blocking and anti-sliding device rises and is larger than the pressure of the upper cavity due to the fact that the PDC drill bit 4 excessively bites, the upward force acting on the power motor exceeds the pre-tightening force of the torque spring 13 to push the mandrel 7 to go upward to compress the upper spring 8, the upward movement of the mandrel 7 reduces the bit biting amount, even, the drill bit can be rapidly lifted away from the bottom of the well, the blocking and sliding effect of the PDC drill bit 4 is timely eliminated, and therefore the PDC drill bit 4 can timely recover normal work.

During conventional directional sliding drilling, the reaction torque on the PDC drill bit 4 generated by the change of the shearing amount is changed greatly, so that the tool face is not controlled stably, and the continuity and speed of drilling are affected. In ordinary rotary drilling and directional sliding drilling time, because of the stratum change, perhaps the driller pressurizes unstably and makes PDC drill bit 4 instantaneous shearing volume change great, the reaction torque who produces on PDC drill bit 4 also changes great, though be unlikely to produce serious card smooth and hold back the pump, but can produce very big drill bit vibration, the continuity and the speed of having influenced the drilling, still can produce the influence to the drill bit life-span, after adding anti-sticking device in the pit, when PDC drill bit 4 shearing volume is instantaneous too big the reaction torque and the lower cavity pressure rise on the anti-sticking device dabber in the pit can both in time eliminate PDC overload, the vibration phenomenon takes place, can effectively control PDC drill bit 4 overload and vibration, and can also be in the stability of the better assurance bottom drilling tool face of directional process.