Ball injector and ball injecting process

Abstract

The invention belongs to the technical field of oil field ball throwing, and discloses a ball throwing device and a ball throwing technology. A first transverse pipe and a vertical pipe body are fixedly connected in a sealed mode, a positioning structure is arranged between the first transverse pipe and the vertical pipe body, and grooves for installing the positioning structure are formed in the first transverse pipe and the vertical pipe body respectively; the direction of the groove of the first transverse pipe is the same as the opening end of the first transverse pipe, the groove of the vertical pipe body is in the vertical direction and is close to the upper end, the connection mode of the second transverse pipe and the vertical pipe body is the same as that of the first transverse pipe, the connection mode of the second ball storage space and the second transverse pipe is the same as that of the first ball storage space, and the end seal is fixedly connected with the first transverse pipe and the second transverse pipe in a sealed mode. The ball feeding rod penetrates through the vertical pipe body, the first transverse pipe, the second transverse pipe and the end seal to form a sealing structure with the end seal, the guide structure is fixedly connected with the second transverse pipe, the positioning structure is arranged between the guide structure and the second transverse pipe, the feeding structure is movably connected with the ball feeding rod, continuous ball throwing operation can be achieved, the blocking condition is avoided, and the sealing system is long in service life.

Description

Technical Field

[0001] The invention belongs to the technical field of oil field ball throwing, relates to a ball throwing device and a ball throwing process, and particularly relates to a continuous ball throwing device and a process for a wellhead. Background Art

[0002] During the on-site operation of the oil field, wellhead ball throwing is a common construction procedure. Ball throwing can form a sealed pressure chamber, and ground pressure can control the movement of downhole tools. Ball throwing can also achieve temporary plugging. The material of the ball can be steel ball, resin ball, etc. In simple cases, the wellhead can be opened directly for ball throwing. Complex cases involve specific issues such as pressure, number of balls thrown, and sealing form, which require special ball throwing devices.

[0003] The Chinese invention patent with announcement number CN103939079A discloses a wellhead ball dropping device for fracturing and acidizing and its operation method, which solves the problem of ball dropping under pressure in the well, but has the following defects and shortcomings: the operation is cumbersome during multiple ball dropping operations, the sealing structure is unreasonable, and the entire sealing system is easily damaged. Summary of the invention

[0004] Aiming at the problem that the existing ball thrower cannot throw balls continuously for multiple times under pressure, the present invention provides a ball thrower and a process, which can ensure that the sealing system is not damaged in the case of multiple continuous throwing.

[0005] The above object of the present invention is achieved through the following technical solutions:

[0006] A ball pitcher, wherein the vertical tube comprises a vertical tube body, a vertical tube lower connecting end, and a vertical tube upper connecting end. The vertical tube body is a hollow structure, and the upper and lower ends are sealed connecting ends, which are respectively fixedly connected to the vertical tube lower connecting end and the vertical tube upper connecting end. The first horizontal tube is sealed and fixedly connected to the vertical tube body. The side of the first horizontal tube has an open end, and the open end is sealed and fixedly connected to the first ball storage space. In order to ensure that the direction of the open end is vertically upward, a positioning structure is provided between the first horizontal tube and the vertical tube body. The first horizontal tube and the vertical tube body respectively have grooves for installing the positioning structure. The orientation of the groove of the first horizontal tube is the same as its open end. The groove of the vertical tube body is in the vertical direction and close to the upper end. The second horizontal tube is connected to the vertical tube body in the same way as the first horizontal tube. The connection method between the second ball storage space and the second transverse tube is the same as that of the first ball storage space. The end seals are fixedly connected to the first transverse tube and the second transverse tube seals respectively. The ball delivery rod passes through the vertical tube body, the first transverse tube, the second transverse tube and the end seal. The ball delivery rod and the end seal form a sealing structure. The guide structure is fixedly connected to the second transverse tube. A positioning structure is provided between the two to ensure that the long opening groove of the guide structure is directed upward. The delivery structure is movably connected to the ball delivery rod. A T-shaped structure is provided at the front end of the delivery structure to match the T-slot of the ball delivery rod. The rear end of the delivery structure is a screw nut structure. The nut is a fixed end. The forward and backward feeding of the ball delivery rod is achieved by rotating the screw. Both ends of the large diameter of the ball delivery rod are limit structures.

[0007] Furthermore, the above-mentioned ball thrower also includes a quick connection structure, which includes a fixed connection end, a connecting piece, and a movable connection end. The fixed connection end is threadedly connected to the lower connection end of the vertical pipe, and the fixed connection end is a step-shaped structure. The connecting piece is sleeved on the fixed connection end through the step. The connecting piece is connected to the movable connection end in a groove. The lower end of the connecting end is connected in a fixed connection with the wellhead, which can be selected according to specific circumstances. There is a sealing structure on the outer surface of the maximum diameter of the fixed connection end and the movable connection end.

[0008] The quick connection structure may also be a structure commonly used in the petroleum industry, such as a union, a flange structure, and the like.

[0009] The first ball storage space includes an upper space, a middle space, a lower space, a sealing device A, and a sealing device B from top to bottom, which are fixedly connected in sequence, and the lower space is sealed and fixedly connected to the first transverse tube.

[0010] Furthermore, the vertical pipe is fixedly connected to the vertical pipe lower connecting end and the vertical pipe upper connecting end respectively by threaded connection or welding connection.

[0011] Furthermore, the ball delivery rod is a stepped cylindrical structure, with a threaded hole at the large diameter, a guide screw installed, and two ball accommodating spaces at the small diameter. The upper surface of the connecting part at the ball accommodating space is arc-shaped and cannot stably support the ball. The threaded hole and the ball accommodating space have the same orientation, both facing upward.

[0012] Furthermore, the distance between the two ball accommodating spaces is half the distance between the two ball storage spaces. The ball storage spaces are evenly distributed on the left and right sides of the vertical tube. The size of the ball accommodating spaces is such that only one ball can enter the ball accommodating space, and two balls cannot enter at the same time, which would cause a jam.

[0013] Furthermore, the width of the long opening slot of the guide structure is greater than the guide screw.

[0014] Furthermore, the specific structure of the feeding structure is not limited to the screw nut structure, and various forms that can realize linear reciprocating motion, such as hydraulic cylinders, linear motors, etc., can also be used. The feeding structure can be manually fed or automatically controlled.

[0015] A ball pitching device and a ball pitching process, comprising the following steps:

[0016] (1) Connect the ball thrower to the wellhead through a quick connection structure;

[0017] (2) The upper connection end of the vertical pipe is connected to the well-killing pipeline;

[0018] (3) The sealing device B at the lower part of the first ball storage space and the second ball storage space is in a closed state, and the sealing device A is in an open state;

[0019] (4) The delivery rod is at the left or right extreme position;

[0020] (5) Load the spheres from the upper space to fill the middle space, but do not affect the normal closing of the sealing device A;

[0021] (6) Close the sealing device A;

[0022] (7) Open sealing device B;

[0023] (8) The feeding structure starts to move. Due to the restriction of the ball storage space of the ball feeding rod, only one ball enters the ball storage space at a time. The feeding structure reciprocates to drop the balls in the first ball storage space and the second ball storage space into the well respectively.

[0024] (9) When the sealing device A can be closed normally, the ball can be reinstalled to achieve continuous operation of multiple balls;

[0025] (10) The process of re-loading the sphere is to close the sealing device A, open the sealing device B, and repeat from step (5);

[0026] (11) When there is no pressure in the oil well, the sealing device A and the sealing device B can be opened, and the balls can be directly loaded from the upper space, and multiple balls can be put into operation continuously.

[0027] The beneficial effects of the present invention compared with the prior art are:

[0028] The ball throwing device of the present invention can perform continuous ball throwing operation without jamming and the sealing system has a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0030] Figure 1 It is a sectional view of the left limit point of the pitching device;

[0031] Figure 2 It is a cross-sectional view of the quick connection structure;

[0032] Figure 3 It is the structural diagram of the ball-holding space at the ball-delivery rod;

[0033] Figure 4 A cross-sectional view of a support rod of a ball-holding space at a ball-delivery rod;

[0034] Figure 5 This is a structural diagram of the first ball storage space 5;

[0035] Figure 6 It is a cross-sectional view of the right limit point of the pitcher.

[0036] Wherein: 1 vertical tube, 2 first horizontal tube, 3 second horizontal tube, 4 end seal, 5 first ball storage space, 6 second ball storage space, 7 ball delivery rod, 8 positioning structure, 9 guide structure, 10 delivery structure, 11 quick connection structure, 101 vertical tube body, 102 vertical tube lower connection end, 103 vertical tube upper connection end, 1101 fixed connection end, 1102 connecting piece, 1103 movable connection end, 501 upper space, 502 middle space, 503 lower space, 504 sealing device A, 505 sealing device B. DETAILED DESCRIPTION

[0037] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical scheme of the present invention is now described in detail in conjunction with the following specific embodiments, but it should not be understood as limiting the scope of the present invention. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the equipment used can be obtained from commercial channels.

[0038] Example 1

[0039] The ball thrower comprises a vertical tube 1, a first horizontal tube 2, a second horizontal tube 3, an end seal 4, a first ball storage space 5, a second ball storage space 6, a ball delivery rod 7, a positioning structure 8, a guide structure 9, a delivery structure 10, and a quick connection structure 11.

[0040] The vertical pipe 1 includes a vertical pipe body 101, a vertical pipe lower connecting end 102, and a vertical pipe upper connecting end 103. The vertical pipe body 101 is a hollow structure, and the upper and lower ends are sealed connecting ends, which are respectively connected to the vertical pipe lower connecting end 102 and the vertical pipe upper connecting end 103. The connecting ends have a sealing structure and are fixedly connected, which can be a threaded connection or a welded connection.

[0041] The lower connecting end 102 of the vertical pipe and the upper connecting end 103 of the vertical pipe are hollow tubes.

[0042] The quick connection structure 11 includes a fixed connection end 1101, a connecting piece 1102, and a movable connection end 1103. The fixed connection end 1101 is threadedly connected to the lower connection end 102 of the vertical pipe. The fixed connection end 1101 is a step-shaped structure. The connecting piece 1102 is sleeved on the fixed connection end 1101 through the step. The connecting piece 1102 is connected to the movable connection end 1103 in a groove. The lower end of the connection end 1103 is connected in a groove and is fixedly connected to the wellhead, which can be selected according to specific circumstances.

[0043] There is a sealing structure at the outer surface of the maximum diameter of the fixed connection end 1101 and the movable connection end 1103.

[0044] The quick connection structure 11 may also be a structure commonly used in the petroleum industry, such as a union, a flange structure, and the like.

[0045] When in use, the connecting piece 1102 is sleeved on the fixed connecting end 1101, the fixed connecting end 1101 is threadedly connected to the lower connecting end 102 of the vertical pipe, and the movable connecting end 1103 is fixedly connected to the wellhead end. The docking is achieved by rotating the connecting piece 1102. If only the threaded structure is used to fix the lower connecting end 102 of the vertical pipe with the wellhead end, the entire ball thrower needs to be rotated, which is complicated to operate and difficult to achieve.

[0046] The first transverse tube 2 is sealed and fixedly connected to the vertical tube body 101. The first transverse tube 2 has an open end on its side, and the open end is sealed and fixedly connected to the first ball storage space 5. To ensure that the direction of the open end is vertically upward, a positioning structure 8 is provided between the first transverse tube 2 and the vertical tube body 101. The first transverse tube 2 and the vertical tube body 101 respectively have grooves for installing the positioning structure 8. The orientation of the groove of the first transverse tube 2 is the same as its open end, and the groove of the vertical tube body 101 is in the vertical direction and close to the upper end.

[0047] The connection method between the second transverse pipe 3 and the vertical pipe body 101 is the same as that of the first transverse pipe 2 .

[0048] The end seals 4 are sealed and fixedly connected to the first cross tube 2 and the second cross tube 3 respectively.

[0049] The ball delivery rod 7 passes through the vertical tube body 101 , the first horizontal tube 2 , the second horizontal tube 3 , and the end seal 4 , and the ball delivery rod 7 and the end seal 4 form a sealing structure.

[0050] The ball delivery rod 7 is a stepped cylindrical structure, with a threaded hole at the large diameter, a guide screw installed, and two ball accommodating spaces at the small diameter. Figure 3 As shown, the upper surface of the connection part of the ball-containing space is arc-shaped and cannot stably support the ball. The threaded hole and the ball-containing space have the same orientation, both facing upward.

[0051] The distance between the two ball-accommodating spaces is half of the distance between the two ball-storing spaces, and the ball-storing spaces are evenly distributed on the left and right sides of the vertical tube. When the ball-delivering rod 7 moves to the limit position, it can be ensured that the ball-accommodating spaces correspond to the ball-storing spaces and the vertical tube respectively.

[0052] The size of the ball holding space should ensure that only one ball can enter the ball holding space, and two balls cannot enter at the same time to avoid jamming.

[0053] The guide structure 9 is fixedly connected to the second transverse pipe 3 , and a positioning structure 8 is provided between the two to ensure that the long opening groove of the guide structure 9 is directed upward.

[0054] The width of the long opening slot of the guide structure 9 is greater than the guide screw, which has a limiting and guiding effect on the guide screw.

[0055] The positioning structure and the guiding structure mentioned above play the role of making the ball-holding space of the ball-delivering rod 7 and the opening end of the horizontal tube have the same orientation, both facing upward.

[0056] The feeding structure 10 is movably connected to the ball feeding rod 7. The front end of the feeding structure 10 is provided with a T-shaped structure, which is adapted to the T-shaped slot of the ball feeding rod 7. The rear end of the feeding structure 10 is a screw nut structure, and the nut is a fixed end. By rotating the screw, the forward and backward feeding of the ball feeding rod 7 is achieved.

[0057] The specific structure of the feeding structure 10 is not limited to the screw nut structure, and various forms that can realize linear reciprocating motion, such as hydraulic cylinders, linear motors, etc., can also be used. The feeding structure 10 can be manually fed or automatically controlled.

[0058] The two ends of the large diameter of the ball delivery rod 7 are limit structures, which respectively contact the end seal 4 and the nut to reach the limit position of moving leftward and rightward.

[0059] The first ball storage space 5 includes an upper space 501, a middle space 502, a lower space 503, a sealing device A 504, and a sealing device B 505, which are connected in the following order: Figure 5 shown.

[0060] The lower space 503 is sealed and fixedly connected to the first transverse pipe 2 .

[0061] The sealing device is a sealing valve with a sufficient diameter to ensure the passage of the ball.

[0062] The seal of the ball pitcher includes a ball delivery rod 7 and an end seal 4, a first transverse tube 2 and a first ball storage space 5, a second transverse tube 3 and a second ball storage space 6, a first transverse tube 2 and a vertical tube 1, a second transverse tube 3 and a vertical tube 1, a vertical tube body 101 and a vertical tube lower connecting end 102, a vertical tube body 101 and a vertical tube upper connecting end 103, and a sealing device A504.

[0063] Except for the ball delivery rod 7 and the end seal 4, other sealing structures are static seals, which have a long sealing life and are not prone to sealing failure.

[0064] The linear reciprocating motion of the ball delivery rod 7 forms a dynamic seal, and the sealing structure is located at both ends, and there is no variable diameter structure passing through the sealing part, which can maximize the life of the sealing part.

[0065] In actual applications, there is no pressure in the oil well, so there is no need to consider the sealing issue.

[0066] The operation method of the pitching device is as follows:

[0067] 1. Connect the ball thrower to the wellhead via the quick connection structure 11.

[0068] 2. The upper connection end 103 of the vertical pipe is connected to the well killing pipeline.

[0069] 3. The sealing device B505 at the bottom of the first ball storage space 5 and the second ball storage space 6 is in a closed state, and the sealing device A504 is in an open state.

[0070] 4. The ball delivery rod 7 is at the left or right extreme position.

[0071] 5. Start loading the spheres from the upper space 501 to fill the middle space 502, but do not affect the normal closing of the sealing device A504.

[0072] 6. Close sealing device A504.

[0073] 7. Open sealing device B505.

[0074] 8. The feeding structure 10 starts to move. Due to the restriction of the ball storage space of the ball feeding rod 7, only one ball enters the ball storage space at a time. The feeding structure 10 reciprocates and puts the balls in the first ball storage space 5 and the second ball storage space 6 into the well respectively.

[0075] 9. When the sealing device A504 can be closed normally, the ball can be reinstalled to achieve continuous operation of multiple balls.

[0076] 10. The process for re-installing the ball is to close the sealing device A504, open the sealing device B505, and repeat from step 5.

[0077] 11. When there is no pressure in the oil well, the sealing device A504 and the sealing device B505 can be opened, and the balls can be directly loaded from the upper space 501, and multiple balls can be put into operation continuously.

[0078] The above-described embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made thereto without departing from the principles and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. A pitching device, characterized in that: The vertical tube (1) comprises a vertical tube body (101), a vertical tube lower connecting end (102), and a vertical tube upper connecting end (103). The vertical tube body (101) is a hollow structure, and the upper and lower ends are sealed connecting ends, which are respectively fixedly connected to the vertical tube lower connecting end (102) and the vertical tube upper connecting end (103). The first horizontal tube (2) is sealed and fixedly connected to the vertical tube body (101). The side of the first horizontal tube (2) has an open end, and the open end is sealed and fixedly connected to the first ball storage space (5). In order to ensure that the direction of the open end is vertically upward, a positioning structure (8) is provided between the first horizontal tube (2) and the vertical tube body (101). The first horizontal tube (2) and the vertical tube body (101) respectively have grooves for installing the positioning structure (8). The orientation of the groove of the first horizontal tube (2) is the same as that of its open end. The groove of the vertical tube body (101) is in the vertical direction and close to the upper end. The second horizontal tube (3 ) is connected to the vertical tube body (101) in the same manner as the first transverse tube (2); the second ball storage space (6) is connected to the second transverse tube (3) in the same manner as the first ball storage space (5); the end seal (4) is sealed and fixedly connected to the first transverse tube (2) and the second transverse tube (3) respectively; the ball delivery rod (7) passes through the vertical tube body (101), the first transverse tube (2), the second transverse tube (3) and the end seal (4); the ball delivery rod (7) and the end seal (4) form a sealing structure; the guide structure (9) is fixedly connected to the second transverse tube (3); a positioning structure (8) is provided between the two to ensure that the long opening groove of the guide structure (9) is directed upward; the delivery structure (10) is movably connected to the ball delivery rod (7); a T-shaped structure is provided at the front end of the delivery structure (10) to match the T-shaped groove of the ball delivery rod (7); and both ends of the large diameter of the ball delivery rod (7) are limit structures.

2. The pitching device according to claim 1, characterized in that: It also includes a quick connection structure (11), which includes a fixed connection end (1101), a connecting piece (1102), and a movable connection end (1103). The fixed connection end (1101) is threadedly connected to the lower connection end (102) of the vertical pipe. The fixed connection end (1101) is a step-shaped structure. The connecting piece (1102) is sleeved on the fixed connection end (1101) through the step. The connecting piece (1102) and the movable connection end (1103) are connected by a groove. The lower end of the groove connection of the connection end (1103) has a form of fixed connection with the wellhead. It is selected according to specific circumstances. The fixed connection end (1101) and the movable connection end (1103) have a sealing structure at the outer surface of the maximum diameter.

3. The pitching device according to claim 2, characterized in that: The quick connection structure (11) is a union and flange structure.

4. The pitching device according to claim 1, characterized in that: The first ball storage space (5) comprises, from top to bottom, an upper space (501), a middle space (502), a lower space (503), a sealing device A (504), and a sealing device B (505), which are fixedly connected in sequence, and the lower space (503) is sealed and fixedly connected to the first transverse tube (2).

5. The pitching device according to claim 1, characterized in that: The vertical pipe body (101) is fixedly connected to the vertical pipe lower connection end (102) and the vertical pipe upper connection end (103) respectively by threaded connection or welding connection.

6. The pitching device according to claim 1, characterized in that: The ball delivery rod (7) is a stepped cylindrical structure, with a threaded hole at the large diameter, a guide screw installed thereon, and two ball accommodating spaces at the small diameter. The upper surface of the connecting part at the ball accommodating space is arc-shaped and cannot stably support the ball. The threaded hole and the ball accommodating space have the same orientation, both facing upward.

7. The pitching device according to claim 6, characterized in that: The distance between the two ball holding spaces is half the distance between the two ball storage spaces. The ball storage spaces are evenly distributed on the left and right sides of the vertical tube. The size of the ball holding spaces is such that only one ball can enter the ball holding space. Two balls cannot enter at the same time, otherwise a jam will occur.

8. The pitching device according to claim 1, characterized in that: The width of the long opening slot of the guide structure (9) is greater than the guide screw.

9. The pitching device according to claim 1, characterized in that: The rear end of the feeding structure (10) is a screw nut structure, and the nut is a fixed end. By rotating the screw, the ball feeding rod (7) can be fed forward and backward. The specific structure of the feeding structure (10) is a screw nut structure, and a hydraulic cylinder or a linear motor is used.

10. A pitching device and a pitching process, characterized in that: The steps include: (1) Connecting the ball thrower to the wellhead via a quick connection structure (11); (2) The upper connection end (103) of the vertical pipe is connected to the well-killing pipeline; (3) The sealing device B (505) at the lower part of the first ball storage space (5) and the second ball storage space (6) is in a closed state, and the sealing device A (504) is in an open state; (4) The ball delivery rod 7 is at the left or right extreme position; (5) The spheres are loaded starting from the upper space (501) to fill the middle space (502), but the normal closing of the sealing device A (504) cannot be affected; (6) Close the sealing device A (504); (7) Open the sealing device B (505); (8) The feeding structure 10 starts to move. Due to the restriction of the ball storage space of the ball feeding rod (7), only one ball enters the ball storage space at a time. The feeding structure (10) reciprocates to drop the balls in the first ball storage space (5) and the second ball storage space (6) into the well respectively. (9) When the sealing device A (504) can be closed normally, the balls can be reinstalled to achieve continuous operation of multiple balls; (10) The process of reloading the sphere is to close the sealing device A (504), open the sealing device B (505), and repeat from step (5); (11) When there is no pressure in the oil well, the sealing device A (504) and the sealing device B (505) can be opened, and the balls can be directly loaded from the upper space (501), and multiple balls can be put into operation continuously.

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