CN107701135B - An emergency detachment device for an underwater Christmas tree - Google Patents

Abstract

The invention discloses an emergency disengagement device for an underwater Christmas tree, which comprises a lifting oil cylinder mechanism, the lifting oil cylinder mechanism is fixedly connected with a clamping mechanism, the clamping mechanism includes an upper cylinder body, the lower end of the upper cylinder body is fixedly connected with a lower cylinder body, The upper cylinder has a built-in piston II, which is set in a shell-like structure. The piston II has a built-in mandrel, and one end of the mandrel passes through the piston II in turn, and the upper cylinder is fixedly connected with the lifting cylinder mechanism. The fourth oil circuit, the third oil circuit is also opened on the mandrel, the inner wall of the lower cylinder is provided with a vertical through groove and an annular groove, the vertical through groove and the annular groove are connected, and a finger-shaped pawl is arranged under the side of the piston II , the pawl extends into the vertical through groove, and a locking block is built in the ring groove. It solves the problem in the prior art that the recovery tool of the underwater Christmas tree has no emergency disconnection device, and the emergency unlocking of the underwater Christmas tree can only be realized by lowering a shearing tool or a special disconnection tool.

Description

An emergency detachment device for an underwater Christmas tree

technical field

The invention belongs to the technical field of offshore oil and gas drilling equipment, and relates to an emergency detachment device for an underwater Christmas tree.

Background technique

With the continuous improvement and improvement of various new technologies and new equipment in the field of offshore oil and gas exploration, more and more underwater Christmas trees are equipped with special recovery tools for installation. At present, if the existing wellhead connector realizes the locking and unlocking of the connection between the subsea tree and the subsea wellhead device by hydraulically driving the lock block, when the subsea tree is installed or recovered during the choke and kill manifold The hydraulic pressure is abnormal, and the liquid cannot be supplied normally; or when severe weather such as typhoon and tsunami occurs, the operation is forced to be interrupted. Since there is no emergency disengagement device for the recovery tool installed on the existing subsea tree, the subsea tree and the subsea wellhead device cannot be separated in time, and the connection part with the subsea tree can only be cut off by running additional equipment or tools, and the water is discarded. Lower the Christmas tree and installation tools, take back the rest, and re-install after the problem is solved, resulting in long operation time and high operating costs, and the cut-off installation tools cannot be reused, resulting in huge economic losses.

Contents of the invention

The object of the present invention is to provide an emergency disconnection device for underwater Christmas trees, which solves the problem that the underwater Christmas tree recovery tool in the prior art has no emergency disconnection device. The problem of emergency unlocking of the lower Christmas tree.

The technical solution adopted in the present invention is an emergency disconnection device for underwater Christmas trees, including a lifting cylinder mechanism, which is fixedly connected with a clamping mechanism, and the clamping mechanism includes an upper cylinder body, and the lower end of the upper cylinder body is fixedly connected There is a lower cylinder, and a piston II is built in the upper cylinder. The piston II is set as a shell structure. The piston II has a built-in mandrel. It is fixedly connected with the lower cylinder so that the clamping mechanism can move up and down with the piston rod. The upper end of the upper cylinder is provided with a fourth oil passage, and the mandrel is also provided with a third oil passage. The inner wall of the lower cylinder is provided with a The vertical through groove is connected with the ring groove, and the vertical through groove is connected with the ring groove. There is a finger-shaped pawl under one side of the piston II, and the pawl extends into the vertical through groove, and a locking block is built in the ring groove.

The present invention is also characterized in that,

The lifting cylinder mechanism includes a cylinder liner. The upper and lower ends of the cylinder liner are respectively threaded to connect the upper end cover and the lower end cover. The cylinder liner has a built-in piston I, and a piston rod is fixedly connected under the piston I. The other end of the piston rod passes through the lower end cover and the core. The shaft is fixedly connected.

The lower end surface of the lower cylinder is fixed with an indicator rod seat, which is hinged with an indicator rod, and the screw head of the telescopic screw is hinged on the indicator rod, and the telescopic screw rod is covered with a spring, and both the telescopic screw and the spring pass through the side of the lower cylinder wall, the telescopic screw passes through the side wall of the lower cylinder and is fixedly connected to the side of the locking block away from the ratchet.

The inner wall of the locking block is provided with toothed locking grooves, and the upper end of the locking block near the pawl is set as a conical surface.

The mandrel is in sealing fit with the piston II and the upper cylinder, the joints of the mandrel, the piston II and the upper cylinder are respectively installed with seal f and seal g, the piston II is in sealing fit with the upper cylinder, and the piston II is in contact with the upper cylinder A seal e is installed at the joint of the body.

The upper end cover and the lower end cover are respectively provided with a first oil passage and a second oil passage, and both the first oil passage and the second oil passage are connected to the inner cavity of the cylinder liner.

The lifting cylinder mechanism also includes a base set as a ring structure, and the lower end cover is fixed on the base.

The piston rod and the lower end cover are sealed, and the seal h is installed at the joint between the piston rod and the lower end cover. The cylinder liner is sealed with the upper end cover and the lower end cover, and the seals are installed at the connection between the cylinder liner and the upper end cover and the lower end cover. a. Seal b. The piston I and the cylinder liner are in a sealing fit, and the seal i is installed at the joint between the piston I and the cylinder liner.

A guide rod is also fixed on the outer circumference of the upper cylinder, and the guide rod is fixed on the upper cylinder through the fastener II.

The beneficial effect of the present invention is that the emergency disconnection device for underwater Christmas tree of the present invention is integrated with the underwater Christmas tree recovery tool, and the clamping mechanism and the clamping mechanism are realized by moving up and down the piston rod of the lifting cylinder mechanism and the clamping mechanism piston. The centering and locking of the emergency release lever of the subsea tree finally achieves the purpose of emergency recovery of the subsea tree. The device of the present invention can be directly integrated on the recovery tool of the underwater Christmas tree, and without changing the structure of the recovery tool and the underwater Christmas tree, the connection between the underwater Christmas tree and the underwater Christmas tree can be realized without inserting a shearing tool or a disconnecting tool. Quick unlocking and disengagement of wellhead devices. This operation can be completed by remotely providing the control fluid. The operation is simple, fast, and repeatable. No special tools are required, and the operation time is short. The invention has a simple and reliable structure, is easy to operate, and has a wide application range. It can be matched with various underwater Christmas tree recovery tools, and realizes the emergency detachment of the underwater Christmas tree through remote hydraulic drive, making preparations for emergency recovery and avoiding forced cutting of the underwater tree X-mas trees reduce operational risks and costs.

Description of drawings

Fig. 1 is the structural representation of a kind of underwater Christmas tree emergency detachment device of the present invention;

Fig. 2 is a schematic diagram of installation of fastener IV of an emergency release device for a subsea tree of the present invention.

In the figure, 1. Upper end cover, 2. Seal a, 3. Piston I, 4. Cylinder liner, 5. Piston rod, 6. Seal b, 7. Lower end cover, 8. Base, 9. Fasteners Ⅰ, 10. Upper cylinder, 11. Piston II, 12. Guide rod, 13. Fastener II, 14. Seal d, 15. Mandrel, 16. Locking block, 17. Lower cylinder, 18. Fastener Ⅲ, 19. Indicator rod seat, 20. Pin Ⅰ, 21. Telescopic screw, 22. Pin Ⅱ, 23. Spring, 24. Indicator rod, 25. Seal e, 26. Seal f, 27. Seal Part g, 28. Fastener Ⅳ, 29. Seal h, 30 Seal i, 31. Fourth oil circuit, 32. Third oil circuit, 33. Vertical through groove, 34. Ring groove, 35. Thorn Claw, 36. Locking groove, 37. First oil passage, 38. Second oil passage, 39. Cavity A, 40. Cavity B, 41. Cavity C, 42. Cavity D.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

An emergency disengagement device for an underwater Christmas tree of the present invention, as shown in Figure 1, includes a lifting cylinder mechanism, and the lifting cylinder mechanism includes an end cover 1, a seal a2, a piston I3, a cylinder liner 4, a piston rod 5, a seal Part b6, lower end cover 7, base 8, fastener I9, seal h29, seal i30, upper end cover 1 and lower end cover 7 are all stepped rotary structures, and are respectively connected to the upper and lower ends of cylinder liner 4 through threads , The upper end cover 1 is provided with a first oil passage, and the lower end cover 7 is provided with a second oil passage. The piston Ⅰ3 is located in the cylinder liner 4, the piston rod 5 passes through the lower end cover 7 and is fixedly connected with the piston Ⅰ3 through threads, and can move up and down along the inner wall of the cylinder liner 4. The seals a2 and b6 are sealed respectively, the piston rod 5 and the lower end cover 7 are sealed and matched through the seal h29, the piston I3 and the cylinder liner 4 are sealed and matched through the seal i30, and the upper end cover 1 and the cylinder liner 4 are sealed. The inner wall, the upper surface of the piston I3, the seal a2, and the seal i30 form a closed variable cavity A39, the lower end cover 7, the inner wall of the cylinder liner 4, the lower surface of the piston I3, the piston rod 5, the seal b6, the seal h29, and The seal i30 forms a sealed variable chamber B40, the first oil passage communicates with the chamber A39, and the second oil passage communicates with the chamber B40. The base 8 is a ring structure for the piston rod 5 to pass through. The base 8 can be the base plate on the subsea tree recovery tool, and is fixedly connected to the bottom of the lower end cover 7 through the fastener I9.

The clamping mechanism consists of upper cylinder 10, piston II11, seal d14, mandrel 15, locking block 16, lower cylinder 17, seal e25, seal f26 and seal g27. The upper cylinder 10 is a rotary structure with a small step hole on the inner wall and a large bottom. The upper end of the upper cylinder 10 is provided with a fourth oil passage. The upper cylinder 10 is fixedly connected with the lower cylinder 17 through threads. The mandrel 15 is Shuttle-shaped rotary body structure, the upper end is fixedly connected with the piston rod 5 through threads, and can move up and down with the piston rod 5, and the lower end of the mandrel 15 is fixedly connected with the lower cylinder 17, so that the clamping mechanism can move up and down with the piston rod 5 Moving, the mandrel 15 and the inner wall of the piston II11 are sealed and matched through the seal f26, and the mandrel 15 is provided with a third oil passage. The inner wall of the lower cylinder 17 is provided with a vertical through groove 33 and an annular groove 34. The piston II 11 is a special-shaped rotary body structure. A finger-shaped pawl 35 is arranged under the piston II 11. The pawl 35 is inserted into the corresponding vertical passage in the lower cylinder 17. In slot 33. The piston II11 and the upper cylinder 10 pass through the upper end of the mandrel 15 in turn, and are set together. The piston II11 can move up and down for a certain distance along the inner wall of the upper cylinder 10, the outer wall of the mandrel and the groove a of the lower cylinder 17. The piston II11 and the upper cylinder The body 10 is sealed and matched through the seal e25, the mandrel 15 and the upper cylinder 10 are sealed and matched through the seal g, the upper cylinder 10, the outer wall of the mandrel 15, the upper surface of the piston II11, the seal e25, the seal f26, and the seal g27 forms a closed variable cavity C41. The inner wall of the piston II11, the outer wall of the mandrel 15, the sealing element d14, the sealing element e25, and the sealing element f26 form a closed variable chamber D42. The third oil passage communicates with the cavity D42, and the fourth oil passage communicates with the cavity C41.

The locking block 16 is a split structure, installed in the ring groove 34 of the lower cylinder 17, and distributed along the circumference; the upper end of the outer wall of the locking block 16 close to the pawl 35 is provided with a tapered surface, and the inner wall is provided with a tooth-shaped locking groove 36; the locking block 16 can move radially to the center for a certain distance under the thrust of the ratchet released by the piston II 11, and the end of the locking block 16 close to the ratchet 35 and the end far away from the ratchet 35 are provided with threaded holes, and the lower cylinder The side wall below 17 is provided with a through hole on the side close to the ratchet 35. As shown in Figure 2, a fastener IV 28 is pierced in the through hole. In the threaded hole on the side of the outer wall of the lock block 16 close to the pawl 35 , select a fastener IV 28 with a suitable length so that the fastener IV 28 can move radially in the lower cylinder 17 with the lock block 16 .

The guide rod 12 and the fastener II13 of the present invention together form a guide structure, the guide rod 12 is fixed to the outer circumference of the upper cylinder 10 through the fastener II13, and can move up and down together with the upper cylinder 10. The guiding structure cooperates with the fixed groove of the subsea tree recovery tool, and plays an auxiliary guiding role when moving up and down.

The locking indicator mechanism includes an indicator rod seat 19, a pin I20, a telescopic screw 21, a pin II22, a spring 23 and an indicator rod 24. The lower part of the indicator rod 24 is connected with the indicator rod seat 19 through the pin I20, and the indicator rod 24 can be wound around the pin When I20 rotates, the indicating rod seat 19 is fixedly connected to the lower end surface of the lower cylinder 17 through the fastener III18, and the telescoping screw 21 is fitted with the spring 23 and then screwed into the threaded hole on the side of the outer wall of the locking block 16 away from the pawl 35 . In a natural state, the spring 23 is in a compressed state, and the locking block 16 radially moves to a limit position under the action of the spring 23 . The non-threaded end of the telescopic screw 21 is connected to the indicator rod 24 via the pin II 22 , and the telescopic screw 21 can rotate around the pin II 22 . The telescopic screw 21 and the spring 23 can radially move a certain distance with the locking block 16, and at this moment, the indicating rod 24 swings with the telescopic screw 21.

The seal a2, seal b6, seal d14, seal e25, seal f26, seal g27, seal h29 and seal i30 of the present invention can be single or multiple seals, and can also be respectively or all metal Seal, non-metallic seal or combined seal; it can also increase the service life of the seal ring by adding a wear-resistant ring to the seal.

In the present invention, the upper end cover 1 and the cylinder liner 4, the cylinder liner 4 and the lower end cover 7, the piston I3 and the piston rod 5, the piston rod 5 and the mandrel 15, and the upper cylinder 10 and the lower cylinder 17 are fixedly connected by threads, It can also be connected by riveting, welding or clamps.

In the present invention, the connection between the lower end cover 7 and the base 8, between the guide rod 12 and the upper cylinder 10, and between the indicating rod seat 19 and the lower cylinder 17 is connected by fasteners, and can also be connected by welding, riveting, etc. .

The working principle of a kind of underwater Christmas tree emergency detachment device of the present invention is:

The state of the underwater Christmas tree: the underwater Christmas tree recovery tool and the emergency detachment device of the present invention are installed, and then the underwater Christmas tree recovery tool and the underwater Christmas tree are installed and locked; the underwater Christmas tree and the underwater wellhead device Connected wellhead connector hydraulic control line disconnected.

Preparation work: pump oil into the cavity B40 through the second oil circuit, so that the piston I3 moves upward to the limit position; pump oil into the cavity D42 through the third oil circuit, so that the piston II11 moves upward to the limit position, and the locking block 16 is in position. Under the action of the spring 23, the locking block 16 moves to the side close to the ratchet 35, and the locking block 16 is unlocked.

The second oil circuit releases the pressure, and pumps oil into the cavity A39 through the first oil circuit, so that the piston I, the piston rod 5 and the clamping mechanism generally move downward to the limit position. At this time, the locking groove 36 of the locking block 16 Align with the ring groove at the upper end of the emergency release lever of the subsea tree. The third oil circuit releases the pressure, and pumps oil into the cavity C41 through the fourth oil circuit, so that the piston II11 moves down to the limit position, and the locking block 16 is squeezed by the pawl 35 of the piston II11. Due to the setting of the cone surface, a The radial force squeezes the locking block 16 to the side away from the ratchet 35, and squeezes the emergency release lever to lock the emergency release lever in the locking groove 36. At this time, the indicating rod 24 rotates counterclockwise , until it is in a vertical state, so that it can be judged that the clamping mechanism is effectively locked with the emergency release lever of the subsea tree. The first oil circuit releases the pressure, and pumps oil into the chamber B40 through the second oil circuit, so that the piston I, the piston rod 5 and the clamping mechanism move upward to the limit position, and finally the submerged tree is lifted by the emergency release lever to unlock. Lift up the subsea tree recovery tool to recover the subsea tree.

Claims (9)

1. An underwater Christmas tree emergency disengagement device, characterized in that it comprises a lifting cylinder mechanism, and the lifting cylinder mechanism is fixedly connected with a clamping mechanism, and the clamping mechanism comprises an upper cylinder (10), the The lower end of the upper cylinder (10) is fixedly connected with the lower cylinder (17), the upper cylinder (10) has a built-in piston II (11), the piston II (11) is set in a shell-like structure, and the piston II (11) A mandrel (15) is built in, and one end of the mandrel (15) passes through the piston II (11), the upper cylinder (10) and is fixedly connected with the lifting cylinder mechanism, and the other end is connected with the lower cylinder (17) ) is fixedly connected as one, the upper end surface of the upper cylinder (10) is provided with a fourth oil passage (31), the mandrel (15) is also provided with a third oil passage (32), and the lower cylinder (17) The inner wall is provided with a vertical through groove (33) and an annular groove (34). The vertical through groove (33) and the annular groove (34) are connected. A ratchet (35), the ratchet (35) extends into the vertical through groove (33), and the ring groove (34) is built with a locking block (16). 2. A kind of underwater Christmas tree emergency disengaging device according to claim 1, characterized in that, the lifting cylinder mechanism comprises a cylinder liner (4), and the upper and lower ends of the cylinder liner (4) are respectively connected by threads There is an upper end cover (1) and a lower end cover (7). The cylinder liner (4) has a built-in piston I (3), and a piston rod (5) is fixedly connected under the piston I (3). The piston rod ( 5) The other end passes through the lower end cover (7) and is fixedly connected with the said mandrel (15). 3. A kind of underwater Christmas tree emergency disengagement device according to claim 1, it is characterized in that, the lower end surface of described lower cylinder (17) is fixed with indicating rod seat (19), and described indicating rod seat (19) ) is hinged with an indicator rod (24), the screw head of the telescopic screw (21) is hinged on the said indicator rod (24), the screw rod of the telescopic screw (21) is covered with a spring (23), and the telescopic screw (21) ) and the spring (23) pass through the side wall of the lower cylinder (17), and the telescoping screw (21) passes through the side wall of the lower cylinder (17) and is away from the pawl (35) with the locking block (16). ) is fixedly connected on one side. 4. A kind of underwater Christmas tree emergency disengaging device according to claim 1, characterized in that, the inner wall of the locking block (16) is provided with toothed locking grooves (36), and the locking block (16) ) near the upper end of one side of the ratchet (35) is set to a tapered surface. 5. A kind of underwater Christmas tree emergency disengaging device according to claim 1, characterized in that, the mandrel (15) is in sealing fit with the piston II (11) and the upper cylinder (10), and the mandrel ( 15) Seals f (26) and seals g (27) are respectively installed at the joints with the piston II (11) and the upper cylinder (10). The piston II (11) and the upper cylinder (10) For sealing fit, a seal e (25) is installed at the joint between the piston II (11) and the upper cylinder (10). 6. A kind of underwater Christmas tree emergency disengaging device according to claim 2, characterized in that, said upper end cover (1) and lower end cover (7) are respectively provided with a first oil passage (37) and a second The oil passage (38), the first oil passage (37) and the second oil passage (38) are all connected to the inner cavity of the cylinder liner (4). 7. A kind of underwater Christmas tree emergency disengagement device according to claim 2, is characterized in that, described lifting oil cylinder mechanism also comprises the base (8) that is arranged as ring structure, and described lower end cover (7) fixed on the base (8). 8. according to claim 2 or 6 or 7 described a kind of underwater Christmas tree emergency disengagement device, it is characterized in that, described piston rod (5) and described lower end cover (7) are sealing fit, piston rod (5) ) and the lower end cover (7) are equipped with a seal h (29), the cylinder liner (4) is in sealing connection with the upper end cover (1) and the lower end cover (7), and the cylinder liner (4) The joints of the upper end cover (1) and the lower end cover (7) are respectively equipped with a seal a (2) and a seal b (6), and the piston I (3) and the cylinder liner (4) ) is a sealing fit, and a seal i (30) is installed at the joint between the piston I (3) and the cylinder liner (4). 9. A kind of underwater Christmas tree emergency disengagement device according to any one of claims 1-7, characterized in that a guide rod (12) is also fixed on the outer circumference of the upper cylinder (10), and the guide The rod (12) is fixed on the upper cylinder (10) by the fastener II (13).