A screw drill bypass valve and screw drill

Abstract

The application relates to a screw drill bypass valve and a screw drill, and belongs to the technical field of drilling equipment. The bypass valve comprises a valve body, a valve sleeve and a valve core are arranged in the valve body, a reset spring is arranged between the valve sleeve and the valve core, a filter hopper is arranged on the side, away from the valve sleeve, of the valve core, the filter hopper is fixedly connected with the valve body, a communication valve is arranged between the filter hopper and the valve core, a filter cylinder is arranged between the communication valve and the filter hopper, the filter cylinder communicates the communication valve and the filter hopper, two ends of the filter cylinder are connected with the communication valve and the filter hopper respectively, an annular cavity is arranged in the side wall of the valve body, a communication pipe is fixedly connected between the communication valve and the inner wall of the valve body, and the communication pipe communicates the communication valve and the annular cavity. The application has the effect of reducing the failure rate of the screw drill.

Description

Technical Field

[0001] This application relates to the technical field of drilling equipment, and in particular to a bypass valve for a screw drill bit and a screw drill bit. Background Technology

[0002] A screw drill is a type of positive displacement downhole power drill that uses drilling fluid as its power source, converting fluid pressure energy into mechanical energy. A screw drill mainly consists of four parts: a bypass valve assembly, a motor assembly, a universal joint assembly, and a drive shaft assembly.

[0003] The bypass valve assembly is located at the top of the drill string. When the drilling fluid flows under pressure through the bypass valve, the valve core closes automatically, and all the drilling fluid is used to drive the screw drill string to work and circulate. When the hydraulic pump is turned off, the bypass valve core moves upward and opens under the action of the return spring. During the lifting of the drill string, the drilling fluid in the drill string is discharged into the well through the bypass channel.

[0004] Regarding the aforementioned technologies, the inventors believe that drilling fluid containing large-particle impurities cannot be separated from the bypass valve. These large-particle impurities accumulate in the bypass valve, thus clogging it. This blockage prevents the drilling fluid from circulating, resulting in a high failure rate of screw drill bits. Summary of the Invention

[0005] To reduce the failure rate of screw drills, this application provides a screw drill bypass valve and a screw drill.

[0006] In the first aspect, this application provides a bypass valve for screw drill bits, which adopts the following technical solution:

[0007] A bypass valve for a screw drill includes a valve body, a valve sleeve and a valve core installed inside the valve body, a return spring installed between the valve sleeve and the valve core, a filter bucket disposed on the side of the valve core away from the valve sleeve, the filter bucket being fixedly connected to the valve body, a connecting valve disposed between the filter bucket and the valve core, a filter cylinder disposed between the connecting valve and the filter bucket, the filter cylinder connecting the connecting valve and the filter bucket, the two ends of the filter cylinder being connected to the connecting valve and the filter bucket respectively, an annular cavity being formed in the side wall of the valve body, a connecting pipe being fixedly connected between the connecting valve and the inner wall of the valve body, the connecting pipe connecting the connecting valve and the annular cavity.

[0008] By adopting the above technical solution, after the drilling fluid enters the valve body, the filter bucket separates large particles of impurities from the drilling fluid, making it difficult for these large particles to flow through the valve sleeve and valve core to the motor assembly. Simultaneously, during the drilling fluid circulation process, the drilling fluid carries the large particles separated by the filter bucket into the filter cylinder. Then, the large particles are squeezed into the connecting valve by the flowing drilling fluid, and finally, they enter the annular cavity through the connecting pipe. Through this structure, large particles of impurities in the drilling fluid are separated and moved from the valve body to the annular cavity. This prevents the bypass valve from becoming clogged due to the accumulation of large particles, thus reducing the failure rate of the screw drill bit.

[0009] Optionally, the two ends of the filter cylinder are rotatably connected to the connecting valve and the filter bucket, respectively. A fixing block is fixedly provided on the circumferential side wall of the filter cylinder. A placement cavity is opened in the fixing block. A knocking ring is provided in the placement cavity. The knocking ring is sleeved on the circumferential side wall of the filter cylinder. There is a gap between the filter cylinder and the fixing block. A water-blocking block is provided on one side of the filter cylinder. The water-blocking block is fixedly connected to the valve body. An installation groove is opened in the water-blocking block. The installation groove penetrates the side wall of the water-blocking block. A drive wheel is provided in the installation groove. One side of the drive wheel extends outward through the installation groove. A rotating roller is fixedly provided in the drive wheel. One end of the rotating roller is rotatably connected to the water-blocking block. A first bevel gear is fixedly connected to the other end of the rotating roller. A second bevel gear that meshes with the first bevel gear is fixedly provided on the circumferential side wall of the filter cylinder.

[0010] By adopting the above technical solution, during the drilling fluid circulation process, the drilling fluid flow causes the drive wheel to rotate, the drive wheel causes the rotating roller to rotate, the rotating roller causes the filter cylinder to rotate through the first bevel gear and the second bevel gear, the filter cylinder causes the fixed block to rotate, and the fixed block causes the striking ring to continuously hit the side wall of the filter cylinder through centrifugal force during rotation. The filter cylinder is vibrated by the impact, and the filter cylinder transmits the vibration to the filter bucket. The vibration keeps large particles of impurities in motion, thereby achieving the effect that the filter cylinder and filter bucket are not easily clogged.

[0011] Optionally, the inner wall of the valve body is provided with a through groove, which communicates with the annular cavity, and a sieve plate is fixedly provided on the inner wall of the valve body at the through groove.

[0012] By adopting the above technical solution, the drilling fluid entering the annular cavity passes through the screen plate and enters the valve body to participate in circulation. Large particles of impurities in the annular cavity are blocked by the screen plate, thereby achieving the effect of replenishing the drilling fluid in the annular cavity to the valve body.

[0013] Optionally, a support cylinder is provided on the side of the filter bucket facing the filter cylinder. A hanging rod is fixedly connected between the support cylinder and the connecting pipe. A striking rod is slidably connected inside the support cylinder. A reset plate is fixedly provided at one end of the striking rod. A first telescopic spring is fixedly provided between the reset plate and the support cylinder. A cam is fixedly provided on the circumferential side wall of the filter cylinder. The cam is used to drive the striking rod to slide.

[0014] By adopting the above technical solution, the rotation of the filter cylinder causes the cam to rotate. During the rotation of the cam, when the protruding part of the cam abuts against the striking rod, the cam squeezes the striking rod to impact the screen plate. When the non-protruding part of the cam abuts against the striking rod, the return spring releases its elastic force and resets the striking rod through the return plate. Through the above structure, the striking rod reciprocates, thereby continuously striking the screen plate, which in turn causes the screen plate to vibrate, achieving the effect of preventing the screen plate from clogging.

[0015] Optionally, the cam has multiple water-permeable holes extending through the side wall of the fixed box.

[0016] By adopting the above technical solution, when the drilling fluid passes through the cam, it can pass through the water-permeable hole of the cam, thereby reducing the cam's obstruction to the circulation of the drilling fluid.

[0017] Optionally, a first connecting ring is fixed on the side of the connecting valve away from the valve core, and the end of the filter cylinder near the connecting valve extends into the first connecting ring. A first connecting block is fixed on the circumferential sidewall of the filter cylinder near the connecting valve. A first connecting groove is circumferentially formed on the sidewall of the first connecting block away from the filter cylinder to slide and adapt to the first connecting ring. A first ball is spherically hinged to the inner wall of the first connecting block at the first connecting groove. A first rolling groove is circumferentially formed on the sidewall of the first connecting ring to adapt to the rolling of the first ball.

[0018] By adopting the above technical solution, the rotation of the filter cartridge causes the first connecting ring to slide in the first connecting groove, while the first connecting block causes the first ball to roll in the first rolling groove, thereby reducing the friction between the first connecting block and the first connecting ring, thus achieving the effect of smooth rotation of the filter cartridge.

[0019] Optionally, a second connecting ring is fixedly provided on the side of the filter bucket near the valve core, and the end of the filter cylinder near the filter bucket extends into the second connecting ring. A second connecting block is fixedly provided on the circumferential side wall of the filter cylinder near the filter bucket. The second connecting block has a second connecting groove circumferentially opened on the side wall away from the filter cylinder, which is slidably adapted to the second connecting ring. A second ball is spherically hinged to the inner wall of the second connecting block at the second connecting groove. The side wall of the second connecting ring has a second rolling groove circumferentially opened, which is adapted to the rolling of the second ball.

[0020] By adopting the above technical solution, the rotation of the filter cylinder causes the second connecting ring to slide in the second connecting groove, while the second connecting block causes the second ball to roll in the second rolling groove, thereby reducing the friction between the second connecting block and the second connecting ring, thus achieving the effect of smooth rotation of the filter cylinder.

[0021] Optionally, the outer wall of the valve body is provided with an external vent, which is connected to the annular cavity. The valve body has a first receiving cavity on the inner wall at the external vent. A stop block is slidably connected in the first receiving cavity. The stop block has a first inclined surface on the side wall facing the annular cavity. A second telescopic spring is fixed between the stop block and the valve body.

[0022] By adopting the above technical solution, when too many large particles of impurities accumulate in the annular cavity, the large particles of impurities will be squeezed by the first inclined surface to the baffle, thereby shrinking the large pieces into the first receiving cavity, thus opening the external discharge port, so that the large particles of impurities in the annular cavity are discharged from the valve body through the external discharge port.

[0023] Optionally, the outer wall of the valve body is provided with a cleaning port that communicates with the annular cavity. A block is provided in the cleaning port, and the side of the block away from the annular cavity extends out of the cleaning port. The inner wall of the valve body at the cleaning port is provided with a second receiving cavity. A locking block is slidably connected in the second receiving cavity. A second inclined surface is provided on both sides of the locking block. A third telescopic spring is fixed between the locking block and the valve body. A locking groove is provided on the surface of the block facing the second receiving cavity to engage with the locking block.

[0024] By adopting the above technical solution, after the drilling work is completed, the staff pulls the plug, and the plug squeezes the block through the second inclined surface, thereby retracting the block into the second receiving cavity. In this way, the staff can remove the plug from the cleaning port, and thus the staff can clean the large particles of impurities in the annular cavity through the cleaning port.

[0025] Secondly, this application provides a screw drill bit, which adopts the following technical solution:

[0026] A screw drill bit, comprising a screw drill bit bypass valve as described in any of the preceding claims.

[0027] By adopting the above technical solution, the bypass valve is less prone to clogging, thereby reducing the failure rate of screw drill bits.

[0028] In summary, this application includes at least one of the following beneficial technical effects:

[0029] 1. The filter bucket separates large particles of impurities from the drilling fluid. The fluidity of the drilling fluid moves these large particles from the valve body to the annular cavity, thus preventing the accumulation of large particles and blockage in the valve body and reducing the failure rate of the screw drill bit.

[0030] 2. The striking ring and striking rod continuously strike the filter cylinder and the sieve plate, causing the filter cylinder and the sieve plate to vibrate. The filter cylinder transmits the vibration to the filter bucket, thereby achieving the effect that the filter cylinder, filter bucket and sieve plate are not easily clogged.

[0031] 3. By adapting the first ball and the first groove, and the second ball and the second groove, the friction generated at both ends of the filter cylinder during rotation is reduced, thus achieving smooth rotation of the filter cylinder. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of a bypass valve for a screw drill according to an embodiment of this application;

[0033] Figure 2 This is a cross-sectional view of a bypass valve for a screw drill according to an embodiment of this application;

[0034] Figure 3 This is a schematic diagram illustrating the internal structure of the valve body in an embodiment of this application;

[0035] Figure 4 This is a partial schematic diagram illustrating the drive wheel mounting method in an embodiment of this application;

[0036] Figure 5 This is a partial cross-sectional view of an embodiment of this application, illustrating the connection relationship between the filter cylinder and the connecting valve, and between the filter cylinder and the filter bucket;

[0037] Figure 6 yes Figure 5 A magnified view of part A in the middle;

[0038] Figure 7 yes Figure 5 A magnified view of part B in the middle section;

[0039] Figure 8 This is a partial cross-sectional view of an embodiment of this application, illustrating the opening and closing methods of the cleaning port and the external leakage port.

[0040] Explanation of reference numerals in the attached drawings: 1. Valve body; 11. Valve sleeve; 12. Valve core; 13. Return spring; 14. Annular cavity; 15. Communicating groove; 151. Sieve plate; 1511. Third filter hole; 16. External vent; 17. First receiving cavity; 171. Stop block; 1711. First inclined surface; 172. Second telescopic spring; 18. Cleaning port; 181. Block; 1811. Slot; 19. Second receiving cavity; 191. Slot block; 1911. Second inclined surface; 192. Third telescopic spring; 2. Filter hopper; 21. First filter hole; 22. Reinforcing plate; 23. Second connecting ring; 231. Second roller groove; 3. Communicating valve; 31 31. Connecting pipe; 32. First connecting ring; 321. First roller groove; 4. Filter cylinder; 41. Second filter hole; 42. Fixing block; 421. Placement cavity; 422. Striking ring; 43. Second bevel gear; 44. Cam; 441. Water permeable hole; 45. First connecting block; 451. First connecting groove; 452. First ball; 46. Second connecting block; 461. Second connecting groove; 462. Second ball; 5. Water blocking block; 51. Mounting groove; 52. Drive wheel; 521. Rotating roller; 5211. First bevel gear; 6. Support cylinder; 61. Hanging rod; 62. Striking rod; 621. Reset plate; 622. First telescopic spring. Detailed Implementation

[0041] The following is in conjunction with the appendix Figure 1-8 This application will be described in further detail.

[0042] This application discloses a bypass valve for screw drills.

[0043] refer to Figure 1 , Figure 2 and Figure 3 A bypass valve for a screw drill includes a valve body 1, a valve sleeve 11, a valve core 12, and a return spring 13 installed inside the valve body 1. The return spring 13 is sleeved on the valve core 12. A filter funnel 2 is provided inside the valve body 1. The filter funnel 2 is funnel-shaped. The side of the filter funnel 2 away from the valve core 12 is fixedly connected to the inner wall of the valve body 1. Several first filter holes 21 are opened through the surface of the filter funnel 2. A connecting valve 3 is provided between the filter funnel 2 and the valve core 12. In this embodiment, the connecting valve 3 is a five-way valve. A filter cylinder 4 is connected between the connecting valve 3 and the filter funnel 2. The filter cylinder 4 is cylindrical. Several second filter holes 41 are opened through the outer wall of the filter cylinder 4. An annular cavity 14 is opened in the inner wall of the valve body 1. A connecting pipe 31 is fixedly connected between the inner wall of the valve body 1 and the connecting valve 3.

[0044] After the drilling fluid enters the valve body 1, it passes through the first filter hole 21, which prevents large particles from passing through the filter bucket 2. During the flow of the drilling fluid, the drilling fluid carries the large particles into the filter cylinder 4 first, and then the drilling fluid carries the large particles from the filter cylinder 4 into the connecting valve 3. Finally, the drilling fluid carries the large particles through the connecting pipe 31 into the annular cavity 14.

[0045] refer to Figure 3 and Figure 4 A water-blocking block 5 is provided on one side of the filter cylinder 4. One side of the water-blocking block 5 is fixedly connected to the inner wall of the valve body 1. An installation groove 51 is provided in the water-blocking block 5. The installation groove 51 passes through the side wall of the water-blocking block 5 facing the filter bucket 2. A drive wheel 52 is provided in the installation groove 51. One side of the drive wheel 52 passes through the installation groove 51 and extends to the outside. A rotating roller 521 is fixedly provided in the drive wheel 52. One end of the rotating roller 521 is rotatably connected to the inner wall of the water-blocking block 5 at the installation groove 51. The other end of the rotating roller 521 passes through the water-blocking block 5 and extends to the outside. A first bevel gear 5211 is fixedly connected to the end of the rotating roller 521 that extends out of the water-blocking block 5. A second bevel gear 43 that meshes with the first bevel gear 5211 is fixedly provided on the circumferential side wall of the filter cylinder 4.

[0046] refer to Figure 3 A reinforcing plate 22 is fixedly provided on the side wall of the filter bucket 2 facing the rotating roller 521. The end of the rotating roller 521 near the filter cylinder 4 passes through the reinforcing plate 22. The rotating roller 521 is rotatably connected to the reinforcing plate 22 around its own central axis.

[0047] During the flow of drilling fluid, the drilling fluid washes the drive wheel 52, thereby driving the drive wheel 52 to rotate. The drive wheel 52 drives the rotating roller 521 to rotate. The rotating roller 521 drives the first bevel gear 5211 to rotate. The first bevel gear 5211 drives the second bevel gear 43 to rotate. The second bevel gear 43 drives the filter cylinder 4 to rotate.

[0048] refer to Figure 3 and Figure 5 The filter cylinder 4 connects the connecting valve 3 and the filter bucket 2. The two ends of the filter cylinder 4 are respectively fitted with a first connecting ring 32 and a second connecting ring 23. Both the first connecting ring 32 and the second connecting ring 23 are ring-shaped. The outer wall of the first connecting ring 32 is fixedly connected to the side of the connecting valve 3 near the filter cylinder 4, and the outer wall of the second connecting ring 23 is fixedly connected to the side of the filter bucket 2 near the filter cylinder 4.

[0049] refer to Figure 5 and Figure 6A first connecting block 45 is fixedly provided on the circumferential side wall of one end of the filter cylinder 4 that extends into the first connecting ring 32. The first connecting block 45 has a first connecting groove 451 that is slidably adapted to the first connecting ring 32 on the side wall opposite to the filter cylinder 4. A plurality of first balls 452 are ball-hinged on the inner wall of the first connecting block 45 at the first connecting groove 451. In this embodiment, three first balls 452 are provided, and the three first balls 452 are located in the same plane. The outer wall of the first connecting ring 32 has a first rolling groove 321 that is adapted to the rolling of the first balls 452.

[0050] refer to Figure 5 and Figure 7 A second connecting block 46 is fixedly provided on the circumferential side wall of one end of the filter cylinder 4 that extends into the second connecting ring 23. The second connecting block 46 has a second connecting groove 461 that is slidably adapted to the second connecting ring 23 on the side wall opposite to the filter cylinder 4. A plurality of second balls 462 are ball-hinged on the inner wall of the second connecting block 46 at the second connecting groove 461. In this embodiment, three second balls 462 are provided, and the three second balls 462 are located in the same plane. The outer wall of the second connecting ring 23 has a second rolling groove 231 that is adapted to the rolling of the second balls 462.

[0051] The filter cylinder 4 rotates, causing the first connecting ring 32 to slide in the first connecting groove 451, while the first ball 452 rolls along the first rolling groove 321; the filter cylinder 4 rotates, causing the second connecting ring 23 to slide in the second connecting groove 461, while the second ball 462 rolls along the second rolling groove 231.

[0052] refer to Figure 3 The filter cylinder 4 is fitted with a fixing block 42 and a cam 44 on its circumferential side wall. The fixing block 42 and the cam 44 are fixedly connected to the outer wall of the filter cylinder 4. The cam 44 has several water-permeable holes 441 through it on the surface facing the fixing block 42.

[0053] refer to Figure 5 The fixing block 42 has a ring-shaped placement cavity 421 inside, and a striking ring 422 is provided inside the placement cavity 421. The striking ring 422 has a ring-shaped structure and is sleeved on the circumferential side wall of the filter cylinder 4. There is a gap between the inner wall of the striking ring 422 and the outer wall of the filter cylinder 4, and there is a gap between the outer wall of the striking ring 422 and the inner side wall of the fixing block 42 at the placement cavity 421.

[0054] The rotation of the filter cartridge 4 drives the cam 44 to rotate, and at the same time, the filter cartridge 4 drives the fixed block 42 to rotate. The rotation of the fixed block 42 drives the striking ring 422 to move, so that the striking ring 422 continuously strikes the outer wall of the filter cartridge 4.

[0055] refer to Figure 2Multiple connecting pipes 31 are provided. In this embodiment, four connecting pipes 31 are provided, and the connecting pipes 31 connect the connecting valve 3 and the annular cavity 14.

[0056] refer to Figure 8 A connecting groove 15 is provided through the inner wall of the valve body 1. The number of connecting grooves 15 is the same as the number of connecting pipes 31. The four connecting grooves 15 are evenly spaced around the central axis of the valve body 1. The connecting grooves 15 are connected to the annular cavity 14. A sieve plate 151 is fixed on the inner wall of the valve body 1 at the connecting groove 15. Several third filter holes 1511 are provided through the side wall of the sieve plate 151 facing the annular cavity 14.

[0057] During the drilling fluid flow, the drilling fluid carries large particles of impurities from the filter cylinder 4 into the connecting valve 3. Then, the drilling fluid carries the large particles of impurities from the connecting valve 3 into the connecting pipe 31. Finally, the drilling fluid carries the large particles of impurities from the connecting pipe 31 into the annular cavity 14. The drilling fluid in the annular cavity 14 passes through the third filter hole 1511 and is replenished into the valve body 1. The large particles of impurities in the annular cavity 14 are intercepted by the third filter hole 1511.

[0058] refer to Figure 8 The outer wall of the valve body 1 is provided with an external vent 16. There are four external vents 16, which are evenly spaced around the central axis of the valve body 1. The external vents 16 are connected to the annular cavity 14.

[0059] refer to Figure 3 A support cylinder 6 is provided around the filter cylinder 4. The number of support cylinders 6 is the same as the number of connecting pipes 31 and they correspond one-to-one. A hanging rod 61 is fixedly connected between the support cylinder 6 and the connecting pipe 31. A striking rod 62 is slidably connected inside the support cylinder 6. A reset plate 621 is sleeved on one end of the striking rod 62 near the filter cylinder 4. The reset plate 621 is fixedly connected to the filter cylinder 4. A first telescopic spring 622 is fixed between the reset plate 621 and the support cylinder 6. The first telescopic spring 622 is sleeved on the circumferential side wall of the striking rod 62.

[0060] During the rotation of cam 44, when the protruding part of cam 44 abuts against the striking rod 62, cam 44 presses against the striking rod 62, thereby causing cam 44 to drive the striking rod 62 to slide. The striking rod 62 compresses the first telescopic spring 622 through the reset plate 621. When the non-protruding part of cam 44 abuts against the striking rod 62, the first telescopic spring 622 releases its elastic force, and the first telescopic spring 622 drives the striking rod 62 to reset through the reset plate 621.

[0061] refer to Figure 8The valve body 1 has a first receiving cavity 17 on the inner wall at the external discharge port 16. A stop block 171 is slidably connected in the first receiving cavity 17. A second telescopic spring 172 is provided in the first receiving cavity 17. The two ends of the second telescopic spring 172 are fixedly connected to the stop block 171 and the inner wall of the valve body 1 at the first receiving cavity 17, respectively. A first inclined surface 1711 is provided on the side wall of the stop block 171 away from the second telescopic spring 172. The first inclined surface 1711 is provided on the side of the stop block 171 facing the annular cavity 14.

[0062] Large particles of impurities are trapped and accumulate in the annular cavity 14. Once the annular cavity 14 is full of large particles of impurities, the large particles of impurities squeeze the first inclined surface 1711, thereby causing the first inclined surface 1711 to contract into the first receiving cavity 17. As a result, the external vent 16 is opened, and the large particles of impurities in the annular cavity 14 are discharged from the valve body 1 through the external vent 16.

[0063] refer to Figure 8 The outer wall of the valve body 1 is provided with a cleaning port 18. There are four cleaning ports 18, which are evenly spaced around the central axis of the valve body 1. The cleaning ports 18 are connected to the annular cavity 14. A block 181 is provided in the cleaning port 18, and the side of the block 181 away from the annular cavity 14 extends out of the cleaning port 18.

[0064] refer to Figure 8 The valve body 1 has a second receiving cavity 19 on its inner wall at the cleaning port 18. There are two second receiving cavities 19, which are respectively located on opposite inner walls of the valve body 1 at the cleaning port 18. A locking block 191 is slidably connected in the second receiving cavity 19. A third telescopic spring 192 is provided in the second receiving cavity 19. The two ends of the third telescopic spring 192 are respectively fixedly connected to the locking block 191 and the inner wall of the valve body 1 at the second receiving cavity 19. The side wall of the locking block 191 away from the third telescopic spring 192 has a second inclined surface 1911. There are two second inclined surfaces 1911, which are located opposite each other on both sides of the locking block 191. The third telescopic spring 192 is fixed between the locking block 191 and the valve body 1. The surface of the plug 181 facing the second receiving cavity 19 has a locking groove 1811 that is adapted to engage with the locking block 191.

[0065] After drilling is completed, the workers pull the plug 181, which compresses the second inclined surface 1911, thereby retracting the block 191 into the second receiving cavity 19. As a result, the cleaning port 18 is opened, and the workers discharge large particles of impurities in the annular cavity 14 from the cleaning port 18 into the valve body 1.

[0066] The implementation principle of a bypass valve for screw drill bits in this application embodiment is as follows: After the drilling fluid enters the valve body 1, it passes through the filter hopper 2, which intercepts large particulate impurities in the drilling fluid. During the flow of the drilling fluid, the large particulate impurities are carried into the filter cylinder 4. Then, the drilling fluid carries the large particulate impurities through the connecting valve 3 and the connecting pipe 31 into the annular cavity 14. Finally, the drilling fluid passes through the screen plate 151 to replenish the valve body 1, and the large particulate impurities are intercepted by the screen plate 151 in the annular cavity 14. Through the above structure, the failure rate of screw drill bits is reduced.

[0067] This application also discloses a screw drill bit.

[0068] A screw drill bit includes the aforementioned screw drill bit bypass valve.

[0069] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A bypass valve for a screw drill bit, comprising a valve body (1), a valve sleeve (11) and a valve core (12) installed inside the valve body (1), and a return spring (13) installed between the valve sleeve (11) and the valve core (12), characterized in that: A filter bucket (2) is provided on the side of the valve core (12) away from the valve sleeve (11). The filter bucket (2) is fixedly connected to the valve body (1). A connecting valve (3) is provided between the filter bucket (2) and the valve core (12). A filter cylinder (4) is provided between the connecting valve (3) and the filter bucket (2). The filter cylinder (4) connects the connecting valve (3) and the filter bucket (2). The two ends of the filter cylinder (4) are respectively connected to the connecting valve (3) and the filter bucket (2). An annular cavity (14) is opened in the side wall of the valve body (1). A connecting pipe (31) is fixedly connected between the connecting valve (3) and the inner wall of the valve body (1). The connecting pipe (31) connects the connecting valve (3) and the annular cavity (14). The two ends of the filter cylinder (4) are rotatably connected to the connecting valve (3) and the filter bucket (2) respectively. A fixing block (42) is fixedly provided on the circumferential side wall of the filter cylinder (4). A placement cavity (421) is opened in the fixing block (421). A knocking ring (422) is provided in the placement cavity (421). The knocking ring (422) is sleeved on the circumferential side wall of the filter cylinder (4). There is a gap between the filter cylinder (4) and the fixing block (42). A water-blocking block (5) is provided on one side of the filter cylinder (4). The water-blocking block (5) is fixedly connected to the valve body (1). An installation groove (51) is provided inside the filter cylinder (4). The installation groove (51) penetrates the side wall of the water-blocking block (5). A drive wheel (52) is provided inside the installation groove (51). One side of the drive wheel (52) extends out to the outside through the installation groove (51). A rotating roller (521) is fixed inside the drive wheel (52). One end of the rotating roller (521) is rotatably connected to the water-blocking block (5). The other end of the rotating roller (521) is fixedly connected to a first bevel gear (5211). A second bevel gear (43) that meshes with the first bevel gear (5211) is fixedly provided on the circumferential side wall of the filter cylinder (4). The inner wall of the valve body (1) is provided with a through groove (15), which is connected to the annular cavity (14). A sieve plate (151) is fixed on the inner wall of the valve body (1) at the through groove (15). The filter bucket (2) is provided with a support cylinder (6) on the side facing the filter cylinder (4). A hanging rod (61) is fixedly connected between the support cylinder (6) and the connecting pipe (31). A striking rod (62) is slidably connected inside the support cylinder (6). A reset plate (621) is fixedly provided at one end of the striking rod (62). A first telescopic spring (622) is fixedly provided between the reset plate (621) and the support cylinder (6). A cam (44) is fixedly provided on the circumferential side wall of the filter cylinder (4). The cam (44) is used to drive the striking rod (62) to slide. The connecting valve (3) is fixed with a first connecting ring (32) on the side away from the valve core (12). The filter cylinder (4) extends into the first connecting ring (32) at the end near the connecting valve (3). The filter cylinder (4) is fixed with a first connecting block (45) on the circumferential side wall near the connecting valve (3). The first connecting block (45) is provided with a first connecting groove (451) that slides and adapts to the first connecting ring (32) on the side wall away from the filter cylinder (4). The first connecting block (45) is ball-hinged with a first ball (452) on the inner wall of the first connecting block (45) at the first connecting groove (451). The first connecting ring (32) is provided with a first rolling groove (321) that rolls and adapts to the first ball (452) on the side wall. A second connecting ring (23) is fixedly provided on the side of the filter bucket (2) near the valve core (12). The end of the filter cylinder (4) near the filter bucket (2) extends into the second connecting ring (23). A second connecting block (46) is fixedly provided on the circumferential side wall of the filter cylinder (4) near the filter bucket (2). A second connecting groove (461) is circumferentially opened on the side wall of the second connecting block (4) away from the filter cylinder (4) and is slidably adapted to the second connecting ring (23). A second ball (462) is ball-hinged on the inner wall of the second connecting block (46) at the second connecting groove (461). A second rolling groove (231) is circumferentially opened on the side wall of the second connecting ring (23) and is adapted to the rolling of the second ball (462).

2. The bypass valve for a screw drill bit according to claim 1, characterized in that: The cam (44) has multiple water-permeable holes (441) through the side wall facing the fixed block (42).

3. A bypass valve for a screw drill bit according to claim 1, characterized in that: The outer wall of the valve body (1) is provided with an external vent (16), which is connected to the annular cavity (14). The valve body (1) has a first receiving cavity (17) on its inner wall at the external vent (16). A stop block (171) is slidably connected in the first receiving cavity (17). The stop block (171) has a first inclined surface (1711) on its side wall facing the annular cavity (14). A second telescopic spring (172) is fixed between the stop block (171) and the valve body (1).

4. A bypass valve for a screw drill bit according to claim 1, characterized in that: The outer wall of the valve body (1) is provided with a cleaning port (18), which is connected to the annular cavity (14). A block (181) is provided in the cleaning port (18). The side of the block (181) away from the annular cavity (14) extends out of the cleaning port (18). The inner wall of the valve body (1) at the cleaning port (18) is provided with a second receiving cavity (19). A locking block (191) is slidably connected in the second receiving cavity (19). A second inclined surface (1911) is provided on both sides of the locking block (191). A third telescopic spring (192) is fixed between the locking block (191) and the valve body (1). A locking groove (1811) is provided on the surface of the block (181) facing the second receiving cavity (19) to fit the locking block (191).

5. A screw drill bit, characterized in that: Includes the screw drill bypass valve as described in any one of claims 1-4.

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