CN111140194A

CN111140194A - A quick reloading device for well head preventer

Info

Publication number: CN111140194A
Application number: CN202010108918.3A
Authority: CN
Inventors: 胡刚; 王锐; 辜思曼; 刘志伟; 黄梦婷
Original assignee: Southwest Petroleum University
Current assignee: Southwest Petroleum University
Priority date: 2020-02-21
Filing date: 2020-02-21
Publication date: 2020-05-12

Abstract

The invention relates to the technical field of oil and gas drilling, well cementation, well completion or pipeline connection, in particular to a quick reloading device for a wellhead blowout preventer, wherein the inner side surface of a locking ring is provided with grooves for containing cam blocks at intervals, the cam blocks are rotationally arranged on a body tube, the outer side surface of a locking end comprises a cam pressure bearing surface and a cam locking surface, the cam pressure bearing surface is a convex curved surface generated by a straight line segment rotating along the rotation center of the cam blocks, the cam locking surface is a plane, and the smooth transition sliding-in end is arranged between the cam pressure bearing surface and the cam locking surface; when the cam locking surface is parallel to the axis of the body pipe, the distance between the cam locking surface and the axis of the body pipe is larger than the radius of the locking ring locking surface, so that the cam locking surface and the locking ring locking surface can form interference fit, and the cam bearing surface extends outwards along the diameter direction of the body pipe from top to bottom, only one set of hydraulic device is needed to drive the locking ring, the structure is simpler, and the cost is low.

Description

A quick reloading device for well head preventer

Technical Field

The invention relates to the technical field of oil and gas drilling, well cementation, well completion or pipeline connection, in particular to a quick reloading device for a wellhead blowout preventer.

Background

The prior art device is a U.S. patent No. US10030461B2, fig. 1, where cam lock 220 can be remotely unlocked. First, by remote hydraulic actuation, the cam lock piston 222 is pushed to extend, causing the cam lock to rotate. Rotation of the cam lock moves the cam lock into an engaged position causing the contact face 225 of the cam lock to force against a boss 254 on the connecting blowout preventer interface pipe 250. And then by remote hydraulic actuation, the lock ring 240 is caused to retract, the lock ring 240 moves downward, and the cam lock is captured. The locking ring serves primarily as a safety device to prevent accidental disengagement of the cam lock in the event of loss of hydraulic pressure.

The prior device mainly has the following problems:

1. the lock ring and the cam lock respectively use one set of hydraulic system, and the whole device uses two sets of hydraulic systems. This is because the lock ring and the cam lock both require a large driving force and move independently of each other, so two sets of hydraulic systems must be used;

2. for the hydraulic system of the cam locks, each cam lock corresponds to a separate hydraulic device, so that the complexity of the structure is increased, and the pressure of each hydraulic device is difficult to keep consistent, so that the pressure between the

cam locks

254 and 225 is not equal, that is, the pressure synchronism is difficult to guarantee, and the axis of the interface pipeline 250 is possibly deviated.

Disclosure of Invention

The invention aims to solve the problems that the existing pipe connecting device of a blowout preventer needs two hydraulic driving systems to cause expensive equipment and complicated driving, and provides a quick reloading device for a wellhead blowout preventer, which can realize the connection locking of pipes only by one hydraulic driving system.

In order to achieve the above purpose, the invention provides the following technical scheme:

a quick replacing device for a wellhead blowout preventer comprises a body pipe, a locking ring and a cam block, wherein the locking ring is arranged on the body pipe in a mode of moving along the axis of the locking ring, grooves for accommodating the cam block are formed in the inner side face of the locking ring at intervals, the upper part and the lower part of the bottom face of each groove are respectively named as a locking ring locking face and a locking ring pressing face, the locking ring locking face is a plane parallel to the axis of the locking ring, and the locking ring pressing face is an inclined face which is inclined from inside to outside of the locking ring from top to bottom;

the anti-blowout device comprises a body pipe, a plurality of cam blocks, a plurality of locking ends and a plurality of cam blocks, wherein the cam blocks are rotatably arranged on the body pipe and are arranged at intervals along the circumferential direction of the body pipe, each cam block comprises a pressing end and a locking end, the pressing ends are cylindrical (used for being matched with arc steps on a blowout preventer interface pipeline), the outer side surface of each locking end comprises a cam pressure bearing surface and a cam locking surface, each cam pressure bearing surface is a convex curved surface generated by a certain straight line segment rotating along the rotating center of the cam block, each cam locking surface is a plane, and the sliding ends are smoothly transited between the cam pressure bearing surfaces and the cam locking surfaces;

when the cam locking surface is parallel to the axis of the body pipe, the distance between the cam locking surface and the axis of the body pipe is larger than the radius of the locking ring locking surface, so that the cam locking surface and the locking ring locking surface can form interference fit, and the cam bearing surface extends outwards along the diameter direction of the body pipe from top to bottom.

Preferably, starting with the cam locking surface parallel to the body tube axis, the cam block is rotated counterclockwise to a position such that the shortest distance of the cam block from the body tube axis is greater than the torus radius.

Preferably, the body tube is provided with an annular chamber, an annular piston is arranged in the annular chamber, so that the annular piston divides the annular chamber into two separated chambers, namely an upper chamber and a lower chamber, the annular piston is provided with a plurality of piston rods at intervals along the axis of the annular piston, and the piston rods are fixedly connected with the locking ring.

Preferably, the quick reloading device for the wellhead blowout preventer further comprises a plurality of connecting shafts which can rotate around the axis of the connecting shafts and are arranged on the body pipe, the connecting shafts are uniformly arranged along the circumferential direction of the body pipe, and one end of each connecting shaft is rotatably provided with the cam block; the cam block further comprises a sliding end, wherein the sliding end, the sliding end and the locking end are sequentially arranged on the cam block from the inside of the body pipe to the outside of the body pipe in the rotating direction, the sliding end is a plane, the cam block rotates to the position where the sliding end is parallel to the axis of the body pipe, the distance between the sliding end and the axis of the body pipe is Lb, and the radius of the convex ring is La, and Lb > La.

Preferably, a weight block is arranged on the cam block, and the weight block is suitably positioned in a way that:

after the cam block keeps balance under the action of gravity, the minimum distance Lt from the cam locking surface to the axis of the body pipe is less than the maximum distance Ls from the locking ring pressing surface to the axis of the body pipe, the radius Lr of the lower end of the connecting pipe is greater than the minimum distance Ly from the pressing end to the axis of the body pipe, and Ly is less than the radius La of the convex ring;

the proper position also enables the slide-in ends of two opposite cam blocks to be arranged in an inverted splay shape.

Compared with the prior art, the invention has the beneficial effects that: the anti-blowout device connector pipeline is connected in a mode of pressing the cam block by the locking ring, only one set of hydraulic device is needed to drive the locking ring, the structure is simpler, and the cost is low; and the integrated multi-rod annular hydraulic cylinder is adopted, so that the pressure of the locking ring to each cam block is almost equal, and further the pressure of the cam blocks to the blowout preventer port is also almost equal, and the condition of axial deviation of the blowout preventer port pipeline is difficult to occur.

Description of the drawings:

fig. 1 is prior art, and the specific meaning of iconic markers can be seen in US10030461B 2;

FIG. 2 is a cross-sectional, isometric illustration of the quick-change apparatus for a wellhead blowout preventer of the present application;

FIG. 3 is a three-dimensional axial view of a cam block of the present application;

4-9 are schematic views of the working process of the present application of putting in, locking and lifting out from the body pipe;

FIG. 10 is a schematic view of a locking ring of the present application;

FIG. 11 is a schematic structural diagram of a cylinder body tube according to the present application;

FIG. 12 is a schematic view of the structure of the cylinder head of the present application;

labeled in the graphs of fig. 2-12: 100-body tube, 110-body tube axis, 120-convex ring, 200-locking ring, 210-groove, 211-locking ring locking surface, 212-locking ring pressing surface, 300-cam block, 310-locking end, 311-cam bearing surface, 312-cam locking surface, 320-pressing end, 330-balancing weight, 340-sliding end, 400-connecting shaft, 500-cylinder tube, 510-piston, 520-piston rod, 521-boss, 530-annular chamber, 531-upper chamber, 532-lower chamber, 540-cylinder cover, 541-annular protrusion and 600-connecting tube.

Detailed Description

The present invention will be described in further detail with reference to test examples and specific embodiments. It should be understood that the scope of the above-described subject matter is not limited to the following examples, and any techniques implemented based on the disclosure of the present invention are within the scope of the present invention.

Referring to fig. 2 to 11, a quick change-over device for a wellhead blowout preventer comprises a body pipe 100, a locking ring 200, a cam block 300, a cylinder pipe 500 and a connecting shaft 400 which can rotate around its axis and is arranged on the body pipe 100, wherein the body pipe 100 is fixedly connected with the cylinder pipe 500 coaxially through a connecting pipe 600, as shown in fig. 2, a piston rod 520 fixedly connected with the locking ring 200 is arranged on the cylinder pipe 500, the piston rod 520 drives the locking ring 200 to be arranged on the body pipe 100 in a manner that the locking ring 200 can move along the axis of the locking ring 200, as shown in fig. 2, 6, 7 and 10, a groove 210 for accommodating the cam block 300 is arranged on the inner side of the locking ring 200 at intervals, as shown in fig. 4 to 10, the upper part and the lower part of the bottom surface of the groove 210 are respectively named as a locking ring locking surface 211 and a pressing surface 212, the locking ring locking surface, the locking ring pressing surface 212 is an inclined surface which is inclined from the inside of the locking ring 200 to the outside of the locking ring 200 from the top to the bottom;

as shown in fig. 2 and 4-9, the cam block 300 is rotatably disposed at one end of the connecting shaft 400, and a plurality of cam blocks 300 are arranged at intervals along the circumferential direction of the body pipe 100, and correspondingly, a plurality of grooves 210 for accommodating the cam blocks 300 are also disposed inside the locking ring 200, as shown in fig. 3-4, the cam blocks 300 include a pressing end 320, a locking end 310 and a sliding end 340, the pressing end 320 is cylindrical and is configured to be engaged with a circular arc step on the bop interface pipe, that is, a step formed between the male ring 120 and the body pipe 100 in the drawing, the outer side of the locking end 310 includes a cam bearing surface 311 and a cam locking surface 312, the cam bearing surface 311 is a convex curved surface generated by a straight line segment rotating along the rotation center of the cam block 300, the cam bearing surface 311 is preferably a circular arc surface, the cam locking surface 312 is a flat surface, and the cam bearing surface 311 and the cam locking surface 312 are smoothly transited, the sliding end 340 of the sliding end 340 is a plane, in the rotating direction from the inside of the body tube 100 to the outside of the body tube 100, the cam block 300 is sequentially provided with a pressing end 320, a sliding end 340 and a locking end 310, which is the relative position relationship of the pressing end 320, the sliding end 340 and the locking end 310, and in addition, when the cam block 300 rotates until the sliding end 340 is parallel to the axis of the body tube 100, as shown in fig. 5, the distance between the sliding end 340 and the axis 110 of the body tube is Lb, the radius of the convex ring 120 is La, and Lb > La; so that when the body tube 100 is inserted into the quick-change device of the present application from top to bottom, the protruding ring 120 on the body tube 100 can pass over the cam block 300 so that the pressing end 320 on the cam block 300 can be engaged with the step on the body tube 100, the step is formed by engaging the upper end surface of the protruding ring 120 with the body tube 100, and the state illustrated in fig. 6 is a state where the pressing end 320 is engaged with the step;

when the cam locking surface 312 is parallel to the axis of the body tube 100, the distance between the cam locking surface 312 and the axis of the body tube 100 is equal to or greater than the radius of the locking ring locking surface 211, and the distance between the cam locking surface 312 and the axis of the body tube 100 is greater than the radius of the locking ring locking surface 211, so that the cam locking surface 312 and the locking ring locking surface 211 form an interference fit to be more fixed in assembly, so that the locking ring 200 can slide down continuously to lock the cam block 300, and an error within 1mm can be allowed, of course, as shown in fig. 4, after the cam block 300 is naturally balanced without external force, the cam bearing surface 311 gradually extends inward from top to bottom in the diameter direction of the body tube 100.

The end 340 is slid in, and the minimum distance Lt from the cam locking surface 312 to the body pipe axis 110 is less than the maximum distance Ls from the locking ring pressing surface 212 to the body pipe axis 110, so that the locking ring can slide down to allow the cam block 300 to enter the groove 210, and can allow the locking ring locking surface 211 to be matched with the cam locking surface 312 to lock the cam block 300, so as to clamp the body pipe 100 of the blowout preventer and prevent the body pipe 100 from being separated.

As shown in fig. 4-9, the cam block 300 is provided with a weight 330, and the weight 330 is properly positioned so as to have the following two functions:

1. after the cam block 300 is balanced under the action of gravity, the minimum distance Lt from the cam locking surface 312 to the body tube axis 110 is less than the maximum distance Ls from the locking ring pressing surface 212 to the body tube axis 110, as shown in fig. 4 in particular, so that the locking ring can move downwards more easily so that the locking ring locking surface 211 is matched with the cam locking surface 312, and in addition, the radius Lr of the lower end of the body tube 100 is greater than the minimum distance Ly from the pressing end 320 to the body tube axis 110, so that the body tube 100 can drive the cam to rotate when moving downwards, and Ly is less than the radius La of the convex ring 120, so that after the pressing end 320 of the cam block 300 is matched with the step of the body tube 100, the body tube 100 is difficult to move upwards to lock the body tube 100, and the firm fixed connection relationship between the body tube 100 and the connecting tube 600 is realized;

2. this proper position also allows the slide-in ends 340 of the two opposing cam blocks 300 to be arranged in an inverted "splay" shape, as shown in fig. 4, when the body tube 100 is moved downward, the cam blocks 300 can rotate in the direction of rotation from the outside of the body tube 100 into the inside of the body tube 100, and when the protruding ring 120 passes over the press-holding end 320, the cam blocks 300 rotate in the opposite direction by their own weight so that the press-holding end 320 engages with the step, resulting in the state shown in fig. 6.

The main working process of the quick replacing device of the present application is shown in fig. 4-9, the initial state is shown in fig. 4, when the body tube 100 and the connecting tube 600 need to be fixedly connected, the body tube 100 is moved to move downwards, the lower end of the body tube 100 starts to contact the sliding-in end 340 of the cam block 300, the downward movement of the body tube 100 drives the cam block 300 to rotate, so that the connection line between the center of gravity of the cam block 300 and the rotation center of the cam block 300 is no longer vertical, the body tube 100 continues to move downwards, the convex ring 120 on the body tube 100 contacts the cam block 300 and follows the body tube 100 to move downwards, the cam block 300 rotates again, so that the convex ring 120 contacts the sliding-in end 340 of the cam block 300, the state shown in fig. 5 is reached, the body tube 100 continues to move downwards, after the convex ring 120 is separated from the sliding-in end 340, the convex ring 120 is separated from the pressing-holding end 320 by a short time contact, and then the convex ring 120, because the connection line between the center of gravity of the cam block 300 and the rotation center of the cam block 300 is no longer in a vertical state, the cam block 300 rotates under the action of its own gravity, so that the pressing end 320 contacts with the step of the body tube 100, and the state shown in fig. 6 is reached, and at this time, the body tube 100 does not go down any more;

then the locking ring 200 moves downward under hydraulic pressure and contacts the cam block 300 to reach the state shown in fig. 7, in which the locking ring pressing surface 212 contacts the cam pressing surface 311, the locking ring 200 gives a force perpendicular to the contact surface to the locking end 310 of the cam block 300 so that the locking end 310 of the cam block 300 gradually approaches the body tube 100, the locking ring 200 continues to descend, the locking ring locking surface 211 of the locking ring 200 contacts the cam locking surface 312 of the cam block 300 so that the locking ring 200 locks the cam block 300, the locking ring 200 continues to descend so that the contact area of the locking ring locking surface 211 and the cam locking surface 312 gradually increases until reaching the state of fig. 8, thereby clamping the body tube 100 so that the body tube 100 is difficult to be separated from the connection tube 600. In the operation process, the pressing end 320 of the cam block 300 is always matched with the convex ring 120 of the blowout preventer interface pipe to press and hold the convex ring 120, specifically, the pressing end 320 of the cam block 300 is a cylindrical surface, the upper end surface of the convex ring 120 is also a cylindrical surface, and the two are matched, so that the pressing end 320 is always matched with the convex ring 120 in the rotation process of the cam block 300;

when the blowout preventer interface pipe needs to be taken out, as shown in fig. 9, only hydraulic pressure needs to be driven to enable the locking ring 200 to move upwards, the locking ring 200 is separated from the cam block 300, and at this time, the blowout preventer interface pipe can be taken out, and of course, in order to enable the blowout preventer interface pipe to be taken out smoothly, the size of the cam block 300 needs to be proper, specifically, the proper size enables the cam block 300 to rotate anticlockwise to a certain position from the condition that the cam locking surface 312 is parallel to the body pipe axis 110, and the shortest distance Lc between the cam block 300 and the body pipe axis 110 is larger than the radius La of the convex ring 120, and at this time, as shown in fig. 9, the blowout preventer interface pipe can be.

For the driving of the piston 510 and the piston rod 520, referring to fig. 2, the cylinder tube 500 is fixedly connected with the body tube 100 by the connection tube 600, the cylinder tube 500 is provided with an annular chamber 530, the annular chamber 530 is provided with the annular piston 510 therein such that the annular piston 510 divides the annular chamber 530 into two separated chambers, an upper chamber 531 and a lower chamber 532, respectively, a plurality of piston rods 520 are arranged at intervals on the annular piston 510 along its own axis, the piston rods 520 are fixedly connected with the locking ring 200 such that the annular piston 510 enables the locking ring 200 to be arranged on the body tube 100 in a movable manner along its own axis under the action of fluid pressure, whereby the locking ring 200 can be operated in the direction of the body tube axis 110, in order to restrict the displacement of the piston 510 such that the piston 510 does not block the inlet of the fluid into the chamber, as shown in fig. 2, a boss 521 is provided on the piston rod 520 to restrict the distance, as shown in fig. 2 and 12, an opening portion of the cylinder head 540 of the hole in which the piston rod 520 is placed is provided with an annular protrusion 541 for limiting an upward travel distance of the piston 510, forming an upper limit of the movement of the piston 510.

Claims

1. A quick replacing device for a wellhead blowout preventer is characterized by comprising a body pipe (100), a locking ring (200) and a cam block (300), wherein the locking ring (200) is arranged on the body pipe (100) in a mode of moving along the axis of the locking ring, grooves (210) for accommodating the cam block (300) are formed in the inner side surface of the locking ring (200) at intervals, the upper part and the lower part of the bottom surface of each groove (210) are respectively named as a locking ring locking surface (211) and a locking ring pressing surface (212), the locking ring locking surface (211) is a plane parallel to the axis of the locking ring (200), and the locking ring pressing surface (212) is an inclined surface which is inclined from the inside of the locking ring (200) to the outside of the locking ring (200) from top to bottom;

the cam block (300) is rotatably arranged on the body tube (100), a plurality of cam blocks are arranged at intervals along the circumferential direction of the body tube (100), the cam block (300) comprises a pressing end (320) and a locking end (310), the pressing end (320) is cylindrical, the outer side surface of the locking end (310) comprises a cam bearing surface (311) and a cam locking surface (312), the cam bearing surface (311) is a convex curved surface generated by a certain straight line segment rotating along the rotating center of the cam block (300), the cam locking surface (312) is a plane, and a smooth transition sliding-in end (340) is arranged between the cam bearing surface (311) and the cam locking surface (312);

when the cam locking surface (312) is parallel to the axis of the body pipe (100), the distance between the cam locking surface (312) and the axis of the body pipe (100) is larger than the radius of the locking ring locking surface (211) so that the cam locking surface (312) and the locking ring locking surface (211) can form an interference fit, and the cam bearing surface (311) extends outwards along the diameter direction of the body pipe (100) from top to bottom.

2. The quick-change device for a wellhead blowout preventer according to claim 1, wherein starting from the cam locking face (312) parallel to the body tubular axis (110), the cam block (300) is rotated counterclockwise to a position such that the shortest distance of the cam block (300) from the body tubular axis (110) is greater than a collar (120) radius.

3. A quick-change device for a wellhead blowout preventer according to claim 1, characterized in that an annular chamber (530) is provided on the body pipe (100), an annular piston (510) is provided in the annular chamber (530) such that the annular piston (510) divides the annular chamber (530) into two separate chambers, an upper chamber (531) and a lower chamber (532), respectively, and a plurality of piston rods (520) are arranged on the annular piston (510) at intervals along its own axis, and the piston rods (520) are fixedly connected with the locking ring (200).

4. The quick reloading device for a wellhead blowout preventer according to claim 1, further comprising a connecting shaft (400) which can rotate around the axis of the connecting shaft and is arranged on the body pipe (100), wherein a plurality of connecting shafts (400) are uniformly arranged along the circumferential direction of the body pipe (100), and one end of each connecting shaft (400) is rotatably provided with the cam block (300); the cam block (300) further comprises a sliding end (340), the cam block (300) is sequentially provided with a pressing end (320), a sliding end (340) and a locking end (310) in the rotating direction of the body tube (100) from the inside to the outside of the body tube (100), the sliding end (340) is a plane, the cam block (300) rotates to the sliding end (340) and the axis of the body tube (100) in parallel, the distance between the sliding end (340) and the axis (110) of the body tube is Lb, and the radius of the convex ring (120) is La, and Lb > La.

5. The quick-change device for a wellhead blowout preventer according to claim 1, wherein a counterweight (330) is provided on the cam block (300), the counterweight (330) being suitably positioned such that:

after the cam block (300) is balanced under the action of gravity, the minimum distance Lt from the cam locking surface (312) to the axis (110) of the body pipe is less than the maximum distance Ls from the locking ring pressing surface (212) to the axis (110) of the body pipe, the radius Lr of the lower end of the connecting pipe (600) is greater than the minimum distance Ly from the pressing end (320) to the axis (110) of the body pipe, and Ly is less than the radius La of the convex ring (120);

the proper position also enables the slide-in ends (340) of two opposite cam blocks (300) to be arranged in an inverted splay shape.