Pipe column clamping device with self-locking function and working method thereof

Abstract

The application discloses a pipe column clamping device with self-locking function and a working method thereof, and relates to the technical field of oil and gas exploitation. The pipe column clamping device comprises a base B, a valve body B fixed on the base B, a counterbore, a through hole and a guide groove sequentially arranged from top to bottom in the valve body B, two limiting columns fixed on the bottom surface of the counterbore, a horizontal groove communicated with the counterbore and arranged in the left and right side walls of the valve body B, and a through groove B communicated with the through hole and arranged in the left and right side walls of the valve body B. A vertical seat B is fixed on the base B and located on the left and right sides of the valve body B, and a clamping mechanism for clamping the pipe column at multiple points is arranged between the two vertical seats B and the valve body B. The pipe column clamping device has the advantages that the clamping block is prevented from retreating, and the pipe column can be firmly clamped.

Description

Technical Field

[0001] This invention relates to the technical field of oil and gas extraction, and in particular to a tubing clamping device with a self-locking function and its working method. Background Technology

[0002] After drilling a wellbore in the formation, a tubing string needs to be run into the wellbore. Under well pressure, the oil and gas in the formation flow sequentially through the bottom port of the tubing string, the tubing string itself, the top port of the tubing string, and finally into the designated downstream equipment. To prevent the tubing string from moving upwards under the pressure of the oil and gas (if the tubing string moves upwards, it will damage the production equipment directly above it and also threaten the personal safety of the surrounding workers), workers will fix a clamp at the wellhead to hold the tubing string in place, thereby preventing it from moving upwards.

[0003] The structure of existing grippers is as follows Figures 1-2 As shown, it includes a base A1 and a valve body A2 fixed on the base A1. Both the base A1 and the valve body A2 have a central hole 3. The valve body A2 has a through groove A4 on the left and right sides of the central hole 3. The top surface of the base A1 and the left and right sides of the valve body A2 are fixed with a stand A5. The outer end face of the two stands A5 is fixed with a hydraulic cylinder 6. The piston rod of the hydraulic cylinder 6 passes through the stand A5, and the extension end is fixed with a clamping block 7 that is slidably installed in the through groove A4. The inner end of the two clamping blocks 7 is provided with an arc-shaped groove 8, which is connected to the central hole 3 in the valve body A2.

[0004] The method of using this clamp to hold the tubing string: R1. Fix the base A1 of the clamp directly above the well hole, ensuring that the center hole 3 inside the base A1 is connected to the well hole; R2. Take out a tube 9 and pass the tube 9 from top to bottom through the center hole 3 of valve body A2 and the center hole 3 of base A1, as follows: Figure 3 As shown, the lower end of the tubing string 9 is finally inserted into the wellbore, and the top end of the tubing string 9 is held by hand. R3. The worker controls the piston rods of both hydraulic cylinders 6 to move towards the tubing string 9. The piston rods drive the clamping blocks 7 to move towards the tubing string 9. When the piston rods of both hydraulic cylinders 6 are extended, the tubing string 9 is just fixed between the arc-shaped grooves 8 of the two clamping blocks 7, thus ultimately clamping the tubing string 9. Figure 4 As shown; R4. Fracturing fluid is injected into the wellbore. The oil and gas in the formation flow sequentially through the bottom port of tubing string 9, tubing string 9, and the top port of tubing string 9, and finally into the designated downstream equipment.

[0005] However, while existing clamping devices can clamp the tubing string 9, they still exhibit the following technical shortcomings in practical use: I. The two clamping blocks 7 only clamp the tubing string 9 at a single point on the horizontal plane, and their clamping force is insufficient. When the oil and gas pressure becomes very high, the oil and gas will push the tubing string 9 upward, so that the tubing string 9 can break free from the clamping of the clamping blocks 7, and then the tubing string 9 will move upward. There is a technical defect that the clamping of the tubing string 9 is not firm.

[0006] II. After prolonged use, the hydraulic oil inside the hydraulic cylinder 6 will naturally leak out, causing the piston rod of the hydraulic cylinder 6 to retract outwards. This retracted piston rod drives the clamping block 7 to retract away from the tubing string 9. The retraction direction of the clamping block 7 is as follows: Figure 4 As indicated by the middle arrow, this method fails to achieve the purpose of clamping the tubing string 9, leading to the interruption of subsequent oil and gas extraction operations.

[0007] Therefore, there is an urgent need for a clamping device and its working method that prevents the clamping block from retracting and can firmly clamp the tubing string. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a pipe clamping device with self-locking function and its working method.

[0009] The objective of this invention is achieved through the following technical solution: a pipe clamping device with self-locking function, which includes a base B and a valve body B fixed on the base B. The valve body B has a countersunk hole, a through hole and a guide groove sequentially opened from top to bottom. Two limiting posts are fixed on the bottom surface of the countersunk hole. The valve body B has a transverse groove connecting the countersunk hole in both the left and right side walls. The valve body B has a through groove B connecting the through hole in both the left and right side walls. The base B is fixed with a stand B on both the left and right sides of the valve body B. A clamping mechanism for clamping the tubing is provided between the two stands B and the valve body B. The clamping mechanism located on the left side includes a hydraulic cylinder fixed on the stand B and a pressurizing cylinder fixed on the top surface of the valve body B. A counterweight is fixed on the piston rod of the pressurizing cylinder. The counterweight passes through the transverse groove and the through groove B in sequence and extends into the guide groove. A connecting rod is hinged to the bottom surface of the extended end of the counterweight. The other end of the connecting rod is hinged to a clamping slide that slides with the guide groove. A semi-circular groove is opened on the inner end of the clamping slide. The piston rod of the hydraulic cylinder passes through the support B and a movable plate is fixed on its extended end. A vertical guide rail and a clamping block are fixed on the right end face of the movable plate. A slider is slidably installed on the vertical guide rail. A vertical pressing block is fixed on the slider, which passes through the transverse groove and the counterweight bar sequentially to the right. The clamping block is slidably installed in the through groove B and sleeved on the outside of the counterweight bar. An arc-shaped groove is opened on the inner end of the clamping block.

[0010] The counterweight has a rectangular groove, and the vertical pressure block slides to the right through the rectangular groove.

[0011] The clamping block has a waist-shaped groove in the middle, and the waist-shaped groove of the clamping block is fitted onto the outside of the counterweight block.

[0012] A slot is provided on the top surface of the left end of the clamping block, and a slot seat is fixed on the bottom surface of the slider, located directly above the slot.

[0013] A hinge seat is fixed on the bottom surface of the counterweight block, and a hinge seat is fixed on the top surface of the clamping slide. Both ends of the connecting rod are respectively hinged to the two hinge seats via pins.

[0014] The two clamping mechanisms are arranged symmetrically on the left and right.

[0015] The clamping device also includes a tubular column and an annular platform welded to the outer surface of the tubular column. The outer diameter of the annular platform is equal to the diameter of the counterbore. Two small straight holes are opened in the annular platform, and the two small straight holes correspond to two limiting posts respectively. The outer diameter of the tubular column is equal to the diameter of the through hole in the valve body B.

[0016] The clamping device also includes a controller, which is electrically connected to the hydraulic cylinder and the pressurizing cylinder via signal lines.

[0017] A method for operating a tubing clamping device with a self-locking function includes the following steps: S1. The worker inserts the lower end of the pipe column through the countersunk hole, through hole, guide groove and base B in sequence. Then, the worker places the two small straight holes in the annular platform on the pipe column onto the outside of the two limiting posts. Then, the annular platform is supported on the bottom surface of the countersunk hole, thus realizing the initial installation of the pipe column. At this time, the pipe column is between the two clamping blocks and also between the two clamping slides. S2. The piston rods of the hydraulic cylinders controlling the two clamping mechanisms extend, and the piston rods drive the moving plate to move towards the tube column. The moving plate drives the vertical guide rail, slider, clamping seat, vertical pressure block, and clamping block to move towards the tube column relative to the stationary counterweight block. When the piston rod of the hydraulic cylinder is fully extended, the vertical pressure block is directly above the annular platform, and at the same time, the arc grooves of the two clamping blocks clamp the tubing. S3. The piston rods of the pressurizing cylinders controlling the two clamping mechanisms extend downwards. The piston rods drive the counterweight blocks to move downwards, the counterweight blocks drive the vertical pressure blocks to move downwards, the vertical pressure blocks drive the slider to move downwards along the vertical guide rail, the slider drives the card seat to move toward the slot on the clamping block, and at the same time, the counterweight blocks also drive the connecting rod to move downwards, the connecting rod drives the clamping slide to move along the guide groove toward the tube column. When the piston rod of the pressurized oil cylinder is fully extended, the bottom end of the clamping seat is inserted into the clamping block's slot to lock the clamping block. At the same time, the semi-circular grooves of the two clamping slides clamp the tubing, and the vertical pressure block presses on the top surface of the annular platform, thus ultimately achieving multi-point clamping of the tubing. S4. Fracturing fluid is injected into the wellbore. The oil and gas in the formation flow sequentially through the bottom port of the tubing string, the tubing string, the top port of the tubing string, and finally into the designated downstream equipment.

[0018] The present invention has the following advantages: it prevents the clamping block from retracting and can firmly clamp the tubing. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a prior art clamping device; Figure 2 for Figure 1 Schematic diagram of the KK cross section; Figure 3 This is a schematic diagram showing the tubing passing through the center hole of valve body A and the center hole of base A from top to bottom; Figure 4 A schematic diagram of how a clamping device in the prior art clamps the tubing; Figure 5 This is an isometric view of the present invention; Figure 6 for Figure 5 M-direction schematic diagram; Figure 7 for Figure 5 Main section diagram; Figure 8 This is an isometric view of valve body B of the present invention; Figure 9 for Figure 8 T-direction schematic diagram; Figure 10 for Figure 8 Main section diagram; Figure 11 This is a schematic diagram of the clamping mechanism on the left side of the present invention; Figure 12 for Figure 11 P-direction schematic diagram; Figure 13 for Figure 11 Main section diagram; Figure 14 This is a schematic diagram showing the connection between the tubular column and the annular stage of the present invention; Figure 15 A schematic diagram illustrating the initial installation of the tubular string; Figure 16 A schematic diagram showing how the tubing is clamped by the arc-shaped grooves of the two clamping blocks; Figure 17This is a schematic diagram showing a vertical pressure block pressing against the top surface of a ring-shaped truncated cone. In the picture: 1-Base A, 2-Valve body A, 3-Center hole, 4-Through groove A, 5-Standing seat A, 6-Hydraulic cylinder, 7-Clamping block, 8-Arc groove, 9-Tube column; 10-Base B, 11-Valve body B, 12-Counterhead, 13-Through hole, 14-Guide groove, 15-Limiting post, 16-Transverse groove, 17-Through groove B, 18-Standing base B; 19-Pressure cylinder, 20-Counterweight block, 21-Connecting rod, 22-Clamping slide, 23-Semi-circular groove, 24-Moving plate, 25-Vertical guide rail, 26-Slider, 27-Vertical pressure block; 28-Oval groove, 29-Card slot, 30-Card seat, 31-Hinge seat, 32-Annular platform, 33-Small straight hole. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings. The scope of protection of the present invention is not limited to the following description: like Figures 5-14 As shown, a pipe clamping device with self-locking function includes a base B10 and a valve body B11 fixed on the base B10. The valve body B11 has a countersunk hole 12, a through hole 13 and a guide groove 14 sequentially opened from top to bottom. Two limiting posts 15 are fixed on the bottom surface of the countersunk hole 12. The left and right side walls of the valve body B11 are each provided with a transverse groove 16 communicating with the countersunk hole 12. The left and right side walls of the valve body B11 are each provided with a through groove B17 communicating with the through hole 13. On the base B10, and on the left and right sides of the valve body B11, there are two upright seats B18. Between the two upright seats B18 and the valve body B11, there are clamping mechanisms for clamping the pipe column at multiple points. The two clamping mechanisms are arranged symmetrically on the left and right.

[0021] The clamping mechanism located on the left side includes a hydraulic cylinder 6 fixed on the stand B18 and a pressurizing cylinder 19 fixed on the top surface of the valve body B11. A counterweight block 20 is fixed on the piston rod of the pressurizing cylinder 19. The counterweight block 20 passes through the transverse groove 16 and the through groove B17 in sequence and extends into the guide groove 14. A connecting rod 21 is hinged to the bottom surface of the extended end of the counterweight block 20. The other end of the connecting rod 21 is hinged to a clamping slide block 22 that slides with the guide groove 14. A semi-circular groove 23 is opened on the inner end of the clamping slide block 22. The piston rod of the hydraulic cylinder 6 passes through the support B18 and a movable plate 24 is fixedly mounted on its extended end. A vertical guide rail 25 and a clamping block 7 are fixedly mounted on the right end face of the movable plate 24. A slider 26 is slidably mounted on the vertical guide rail 25. A vertical pressing block 27 is fixedly mounted on the slider 26, which passes through the transverse groove 16 and the counterweight block 20 sequentially to the right. The clamping block 7 is slidably mounted in the through groove B17 and sleeved on the outside of the counterweight block 20. An arc-shaped groove 8 is opened on the inner end of the clamping block 7. An oblong groove 28 is opened in the middle of the clamping block 7, and the oblong groove 28 of the clamping block 7 is sleeved on the outside of the counterweight block 20.

[0022] A rectangular groove is formed inside the counterweight block 20, and the vertical pressure block 27 slides to the right through the rectangular groove. A hinge seat 31 is fixed on the bottom surface of the counterweight block 20, and a hinge seat 31 is fixed on the top surface of the clamping slide block 22. Both ends of the connecting rod 21 are respectively hinged to the two hinge seats 31 via pins.

[0023] A slot 29 is formed on the top surface of the left end of the clamping block 7, and a seat 30 located directly above the slot 29 is fixed on the bottom surface of the slider 26. The clamping device also includes a tube column 9 and an annular platform 32 welded to the outer cylindrical surface of the tube column 9. The outer diameter of the annular platform 32 is equal to the diameter of the countersunk hole 12. Two small straight holes 33 are formed in the annular platform 32, and the two small straight holes 33 correspond to the two limiting posts 15 respectively. The outer diameter of the tube column 9 is equal to the diameter of the through hole 13 in the valve body B11.

[0024] The clamping device also includes a controller, which is electrically connected to the hydraulic cylinder 6 and the pressurizing cylinder 19 via a signal line. The controller can control the extension or retraction of the piston rods of the hydraulic cylinder 6 and the pressurizing cylinder 19.

[0025] A method for operating a tubing clamping device with a self-locking function includes the following steps: S1. The worker inserts the lower end of the pipe column 9 downwards through the countersunk hole 12, through hole 13, guide groove 14, and base B10 in sequence. Then, the worker fits the two small straight holes 33 in the annular platform 32 on the pipe column 9 onto the outside of the two limiting posts 15. The annular platform 32 is then supported on the bottom surface of the countersunk hole 12, thus achieving the initial installation of the pipe column 9. Figure 15 As shown, at this time, the tubing 9 is between the two clamping blocks 7, and at the same time, the tubing 9 is also between the two clamping slides 22; S2. The piston rods of the hydraulic cylinders 6 that control the two clamping mechanisms extend, and the piston rods drive the moving plate 24 to move toward the column 9. The moving plate 24 drives the vertical guide rail 25, the slider 26, the card seat 30, the vertical pressure block 27, and the clamping block 7 to move toward the column 9 relative to the stationary counterweight block 20. When the piston rod of the hydraulic cylinder 6 is fully extended, the vertical pressure block 27 is directly above the annular platform 32. At the same time, the arc-shaped grooves 8 of the two clamping blocks 7 clamp the tubing 9. Figure 16 As shown; S3. The piston rods of the pressurizing cylinders 19 controlling the two clamping mechanisms extend downwards. The piston rods drive the counterweight block 20 to move downwards. The counterweight block 20 drives the vertical pressure block 27 to move downwards. The vertical pressure block 27 drives the slider 26 to move downwards along the vertical guide rail 25. The slider 26 drives the card seat 30 to move toward the card slot 29 on the clamping block 7. At the same time, the counterweight block 20 also drives the connecting rod 21 to move downwards. The connecting rod 21 drives the clamping slide 22 to move along the guide groove 14 toward the column 9. When the piston rod of the pressurizing cylinder 19 is fully extended, the bottom end of the retainer 30 is inserted into the retaining groove 29 of the clamping block 7 to lock the clamping block 7. At the same time, the semi-circular grooves 23 of the two clamping slides 22 clamp the tubing 9. Figure 17 As shown, simultaneously, the vertical pressure block 27 presses against the top surface of the annular platform 32, as... Figure 17 As shown, this ultimately achieved multi-point clamping of the pipe string 9; In step S3, it is known that when the piston rod of the pressurizing cylinder 19 extends downward, the bottom end of the retainer 30 inserts into the slot 29 of the clamping block 7, thereby locking the clamping block 7. Therefore, even if the hydraulic oil in the hydraulic cylinder 6 leaks out naturally, the piston rod of the hydraulic cylinder 6 cannot drive the clamping block 7 to retract away from the tubing 9, compared to... Figures 1-4 The clamp shown ensures that the clamping block 7 can always clamp the tubing string 9, ensuring that the mining operation can continue without interruption.

[0026] S4. Fracturing fluid is injected into the wellbore. The oil and gas in the formation flow sequentially through the bottom port of tubing string 9, tubing string 9, and the top port of tubing string 9, and finally into the designated downstream equipment.

[0027] In step S2, the piston rods of the hydraulic cylinders 6 of the two clamping mechanisms are first extended, so that the pipe column 9 can be clamped on the horizontal plane by the two clamping blocks 7, thus achieving the first point clamping of the pipe column 9. Then, in step S3, the piston rods of the pressurizing cylinders 19 of the two clamping mechanisms are extended downward, so that the pipe column 9 can be clamped on the horizontal plane by the two clamping slides 22, thus achieving the second point clamping of the pipe column 9. At the same time, the vertical pressure block 27 is pressed on the top surface of the annular platform 32, so that the annular platform 32 is clamped between the bottom surface of the countersunk hole 12 and the vertical pressure block 27 on the vertical plane, thus clamping the pipe column 9 on the vertical plane, thus achieving the third point clamping of the pipe column 9.

[0028] Therefore, compared with the existing clamping device which clamps the tubing string 9 at a single point on a horizontal plane, this clamping device achieves multi-point clamping of the tubing string 9, with a greater clamping force, thus clamping the tubing string 9 more firmly. Therefore, when the downhole oil and gas pressure becomes very high, the oil and gas cannot push the tubing string 9 upward and cause it to move upward, thereby avoiding safety hazards.

Claims

1. A tubing clamping device with a self-locking function, characterized in that: It includes a base B (10) and a valve body B (11) fixed on the base B (10). The valve body B (11) has a countersunk hole (12), a through hole (13) and a guide groove (14) sequentially opened from top to bottom. Two limiting posts (15) are fixed on the bottom surface of the countersunk hole (12). The valve body B (11) has a transverse groove (16) connecting the countersunk hole (12) in both the left and right side walls. The valve body B (11) has a through groove B (17) connecting the through hole (13) in both the left and right side walls. The base B (10) is fixed with a stand B (18) on both the left and right sides of the valve body B (11), and a clamping mechanism for clamping the pipe column at multiple points is provided between the two stands B (18) and the valve body B (11). The clamping mechanism located on the left side includes a hydraulic cylinder (6) fixed on the stand B (18) and a pressurizing cylinder (19) fixed on the top surface of the valve body B (11). A counterweight block (20) is fixed on the piston rod of the pressurizing cylinder (19). The counterweight block (20) passes through the transverse groove (16) and the through groove B (17) in sequence and extends into the guide groove (14). A connecting rod (21) is hinged to the bottom surface of the extended end of the counterweight block (20). The other end of the connecting rod (21) is hinged to a clamping slide (22) that slides with the guide groove (14). A semi-circular groove (23) is opened on the inner end of the clamping slide (22). The piston rod of the hydraulic cylinder (6) passes through the support B (18) and a moving plate (24) is fixed on the extended end. A vertical guide rail (25) and a clamping block (7) are fixed on the right end face of the moving plate (24). A slider (26) is slidably installed on the vertical guide rail (25). A vertical pressing block (27) is fixed on the slider (26) and passes through the transverse groove (16) and the counterweight block (20) sequentially to the right. The clamping block (7) is slidably installed in the through groove B (17) and sleeved on the outside of the counterweight block (20). An arc groove (8) is opened on the inner end of the clamping block (7).

2. The pipe clamping device with self-locking function according to claim 1, characterized in that: A rectangular groove is provided inside the counterweight block (20), and the vertical pressure block (27) slides to the right through the rectangular groove.

3. A pipe clamping device with self-locking function according to claim 2, characterized in that: The clamping block (7) has a waist-shaped groove (28) in the middle, and the waist-shaped groove (28) of the clamping block (7) is fitted onto the outside of the counterweight block (20).

4. A pipe clamping device with self-locking function according to claim 3, characterized in that: A slot (29) is provided on the top surface of the left end of the clamping block (7), and a seat (30) located directly above the slot (29) is fixed on the bottom surface of the slider (26).

5. A pipe clamping device with self-locking function according to claim 4, characterized in that: A hinge seat (31) is fixed on the bottom surface of the counterweight block (20), and a hinge seat (31) is fixed on the top surface of the clamping slide (22). Both ends of the connecting rod (21) are respectively hinged to the two hinge seats (31) via pins.

6. A pipe clamping device with self-locking function according to claim 5, characterized in that: The two clamping mechanisms are arranged symmetrically on the left and right.

7. A pipe clamping device with self-locking function according to claim 6, characterized in that: The clamping device also includes a tube column (9) and an annular platform (32) welded to the outer cylindrical surface of the tube column (9). The outer diameter of the annular platform (32) is equal to the diameter of the countersunk hole (12). Two small straight holes (33) are opened in the annular platform (32), and the two small straight holes (33) correspond to two limiting posts (15) respectively. The outer diameter of the tube column (9) is equal to the diameter of the through hole (13) in the valve body B (11).

8. A pipe clamping device with self-locking function according to claim 7, characterized in that: The clamping device also includes a controller, which is electrically connected to the hydraulic cylinder (6) and the pressurizing cylinder (19) via a signal line.

9. A method for operating a pipe clamping device with a self-locking function, comprising the pipe clamping device with a self-locking function as described in claim 8, characterized in that: It includes the following steps: S1. The worker inserts the lower end of the pipe column (9) through the countersunk hole (12), through hole (13), guide groove (14) and base B (10) in sequence. Then, the worker places the two small straight holes (33) in the annular platform (32) on the pipe column (9) onto the outside of the two limiting posts (15). Then, the annular platform (32) is supported on the bottom surface of the countersunk hole (12) to achieve the initial installation of the pipe column (9). At this time, the pipe column (9) is between the two clamping blocks (7) and the pipe column (9) is also between the two clamping slides (22). S2. The piston rods of the hydraulic cylinders (6) controlling the two clamping mechanisms are extended. The piston rods drive the moving plate (24) to move toward the column (9). The moving plate (24) drives the vertical guide rail (25), slider (26), card seat (30), vertical pressure block (27), and clamping block (7) to move toward the column (9) relative to the stationary counterweight block (20). When the piston rod of the hydraulic cylinder (6) is fully extended, the vertical pressure block (27) is just above the annular platform (32), and at the same time, the arc grooves (8) of the two clamping blocks (7) clamp the tubing (9); S3. The piston rods of the pressurizing cylinders (19) controlling the two clamping mechanisms extend downwards. The piston rods drive the counterweight block (20) to move downwards. The counterweight block (20) drives the vertical pressure block (27) to move downwards. The vertical pressure block (27) drives the slider (26) to move downwards along the vertical guide rail (25). The slider (26) drives the card seat (30) to move toward the card slot (29) on the clamping block (7). At the same time, the counterweight block (20) also drives the connecting rod (21) to move downwards. The connecting rod (21) drives the clamping slide (22) to move along the guide groove (14) toward the column (9). When the piston rod of the pressurizing cylinder (19) is fully extended, the bottom end of the card seat (30) is inserted into the slot (29) of the clamping block (7) to lock the clamping block (7). At the same time, the semi-circular grooves (23) of the two clamping slides (22) clamp the pipe string (9). Meanwhile, the vertical pressure block (27) presses on the top surface of the annular platform (32), thus finally realizing the multi-point clamping of the pipe string (9). S4. Fracturing fluid is injected into the wellbore. The oil and gas in the formation flow sequentially through the bottom port of the tubing string (9), the tubing string (9), the top port of the tubing string (9), and finally into the designated downstream equipment.

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