CN118029938A - Well drop preventing device - Google Patents

Abstract

The invention belongs to the technical field of oilfield operation, and discloses a well drop prevention device which comprises a trigger mechanism, an actuating mechanism and a linkage mechanism. The trigger mechanism comprises a trigger cylinder, a trigger piston assembly and an air supply assembly, the trigger cylinder is arranged on the blowout prevention box, the trigger piston assembly is movably inserted into the trigger cylinder and extends into the blowout prevention box to abut against the continuous oil pipe, the trigger piston assembly acts, and the air supply assembly is selectively communicated with the trigger cylinder; the execution mechanism comprises a barrel assembly, a slip assembly, a plurality of execution cylinders and a plurality of execution piston assemblies, wherein the continuous oil pipe penetrates through the barrel assembly, the slip assembly is sleeved outside the continuous oil pipe, the execution cylinders are circumferentially arranged on the barrel assembly, the execution piston assemblies are movably inserted into the execution cylinders respectively, and the execution piston assemblies are connected with the slip assembly respectively; the linkage mechanism is communicated with the trigger cylinder and the execution cylinder, and the compressed air controls the action of the execution piston assembly to change the inner diameter of the slip assembly. The anti-drop well device can act when the coiled tubing breaks, and the anti-drop reliability is improved.

Description

Well drop preventing device

Technical Field

The invention relates to the technical field of oilfield operation, in particular to a well drop prevention device.

Background

The coiled tubing is a tubing made of low-carbon alloy steel, and has good flexibility, which is also called as a flexible tubing. The continuous oil pipe operation equipment has the characteristics of pressurized operation and continuous lifting, and has the advantages of small equipment volume, short operation period, low operation cost and the like. At present, continuous operation oil pipe equipment is widely applied to oilfield operation. The clamping block of the injection head of the continuous oil pipe can be damaged in the operation process, the problems of untimely treatment and the like when the continuous oil pipe is in contact with the blockage in the descending process can be caused, and the phenomenon can cause the unsupported section (gap) of the continuous oil pipe between the injection head chain and the blowout prevention box to be broken, so that the accident of falling into the well of the continuous oil pipe can be caused.

The distance from the triggering end to the executing end of the continuous oil pipe provided by the prior art is larger, so that the length of the well-falling prevention device is too long, and the installation and use difficulty of equipment is increased; meanwhile, the transmission process from the triggering end to the executing end of the continuous oil pipe is complex, the problem of execution delay can occur, and the reliability is difficult to guarantee.

Accordingly, there is a need for a well-drop prevention device that solves the above problems.

Disclosure of Invention

The invention aims to provide a well drop prevention device which can timely act when a continuous oil pipe breaks, so that the reliability of drop prevention is improved.

To achieve the purpose, the invention adopts the following technical scheme:

a well-drop prevention device comprising: the device comprises a trigger mechanism, an actuating mechanism and a linkage mechanism;

The trigger mechanism comprises a trigger cylinder, a trigger piston assembly and an air supply assembly, the trigger cylinder is arranged on the blowout prevention box, the trigger piston assembly is movably inserted into the trigger cylinder and extends into the blowout prevention box to abut against the continuous oil pipe, the trigger piston assembly acts to drive the air supply assembly to selectively communicate with the trigger cylinder, and the air supply assembly is configured to provide compressed air for the trigger cylinder;

The actuating mechanism comprises a barrel assembly, a slip assembly, a plurality of actuating cylinders and a plurality of actuating piston assemblies, wherein the barrel assembly is arranged between the blowout prevention box and a wellhead, the continuous oil pipe penetrates through the barrel assembly and stretches into the well, the slip assembly is positioned in the barrel assembly and sleeved outside the continuous oil pipe, the actuating cylinders are uniformly arranged on the outer side part of the barrel assembly along the circumferential direction, and the actuating piston assemblies are movably inserted into the actuating cylinders in a one-to-one correspondence manner and stretch into the barrel assembly and are movably connected to the slip assembly respectively;

the linkage mechanism is communicated with the trigger cylinder and the execution cylinder, and the compressed air can control the execution piston assembly to act so as to change the inner diameter of the slip assembly.

As the preferable scheme of the well drop prevention device provided by the invention, the trigger piston assembly comprises a trigger piston and a trigger piston rod, the trigger piston rod is coaxially and fixedly connected with the trigger piston, the trigger mechanism further comprises a trigger elastic element, and the trigger elastic element is clamped between the inner wall of one end of the trigger cylinder, which is far away from the blowout prevention box, and the trigger piston, so that the trigger piston rod can be abutted against the continuous oil pipe.

As the preferable scheme of the well drop prevention device provided by the invention, the execution piston assembly comprises an execution piston, an execution piston rod and a slip connecting rod, wherein the execution piston rod is coaxially and fixedly connected with the execution piston, one end of the execution piston rod extends into the cylinder assembly, and two ends of the slip connecting rod are respectively hinged with the end part of the execution piston rod extending into the cylinder assembly and one part of the slip assembly;

The actuating piston is close to the barrel assembly, the slip assembly is gradually far away from the actuating cylinder along the length direction of the continuous oil pipe, and the inner diameter of the slip assembly is reduced;

The actuating piston is far away from the barrel assembly, the slip assembly gradually approaches the actuating cylinder along the length direction of the continuous oil pipe, and the inner diameter of the slip assembly is increased.

As the preferable scheme of the well drop prevention device provided by the invention, the relative positions of the peripheral parts of the trigger cylinders are respectively provided with an air inlet interface and an air outlet interface, and the air supply assembly is communicated with the air inlet interface;

an inner side interface and an outer side interface are arranged at intervals along the length direction of the execution cylinder, and the inner side interface and the outer side interface are selectively communicated with the exhaust interface through the linkage mechanism; the execution piston is located between the inner side interface and the outer side interface, and the air pressure difference between the inner side interface and the outer side interface can drive the execution piston to move along the length direction of the execution cylinder.

As the preferable scheme of the well drop prevention device provided by the invention, the ventilation ring groove is annularly arranged along the peripheral side part of the trigger piston, the trigger piston is close to the blowout prevention box along the length direction of the trigger cylinder, and the air inlet interface, the air outlet interface and the ventilation ring groove are communicated.

As the preferable scheme of the well drop prevention device provided by the invention, the trigger piston assembly further comprises a first sealing ring, a second sealing ring and a third sealing ring, wherein the first sealing ring, the second sealing ring and the third sealing ring are arranged on the trigger piston in a spacing way along the length direction of the trigger piston, the first sealing ring and the second sealing ring are respectively arranged on two sides of the ventilation ring groove, and when the trigger piston rod abuts against the continuous oil pipe, the third sealing ring and the second sealing ring are respectively arranged on two sides of the air inlet interface.

As the preferable scheme of the well drop prevention device provided by the invention, the linkage mechanism comprises a reversing valve and a ventilation valve, the reversing valve controls the ventilation valve to be communicated with the inner side interface, and the outer side interface is communicated with the exhaust interface; or the reversing valve controls the ventilation valve to be communicated with the outer side interface, and the inner side interface is communicated with the exhaust interface.

As a preferable scheme of the well drop preventing device provided by the invention, the execution cylinder comprises an execution cylinder body, an execution cylinder seat and an execution cylinder cover, wherein the execution cylinder seat is arranged on the cylinder body assembly, the execution cylinder body is arranged on the execution cylinder seat, the execution cylinder cover is buckled at one end of the execution cylinder body far away from the execution cylinder seat, and the execution piston is arranged in the execution cylinder body;

the execution cylinder seat is provided with a first buffer groove on one side opposite to the execution piston, the execution cylinder cover is provided with a second buffer groove on one side opposite to the execution piston, and the shapes of the first buffer groove and the second buffer groove are respectively matched with the shapes of two ends of the execution piston.

As a preferable scheme of the well drop preventing device provided by the invention, the actuating mechanism further comprises an actuating elastic element, wherein the actuating elastic element is clamped between the actuating cylinder seat and the actuating piston and is configured to push the actuating piston away from the actuating cylinder seat.

As the preferable scheme of the well drop prevention device provided by the invention, the slip assembly comprises a plurality of slips uniformly arranged along the circumferential direction of the continuous oil pipe, and each group of the execution cylinder and the execution piston assembly can respectively drive one slip to move along the length direction of the continuous oil pipe;

the cylinder assembly comprises a cylinder body and a base, the base is arranged on the inner side of the bottom of the cylinder body, the execution cylinder is mounted on the upper side of the side part of the cylinder body, the base is provided with a guide through hole, the guide through hole is gradually far away from the execution cylinder along the length direction of the continuous oil pipe, the hole wall of the guide through hole is gradually close to the central axis of the base, and a plurality of slips respectively prop against the inner wall of the guide through hole;

when the slips are gradually far away from the execution cylinder along the length direction of the continuous oil pipe, the slips are mutually close to each other until the slips are abutted against the continuous oil pipe.

The invention has the beneficial effects that:

The well drop prevention device provided by the invention comprises a trigger mechanism, an actuating mechanism and a linkage mechanism. The trigger mechanism comprises a trigger cylinder, a trigger piston assembly and an air supply assembly, wherein the trigger cylinder is arranged on the blowout prevention box, the trigger piston assembly is movably inserted into the trigger cylinder and extends into the blowout prevention box to abut against the continuous oil pipe, the trigger piston assembly acts to drive the air supply assembly to selectively communicate with the trigger cylinder, and the trigger piston assembly is configured to provide compressed air for the trigger cylinder. That is, when the coiled tubing breaks down, the blocking effect of the coiled tubing on the trigger piston assembly is eliminated, and at the moment, the trigger piston assembly acts, so that the air supply assembly selectively communicates with the trigger cylinder. The actuating mechanism comprises a barrel assembly, a slip assembly, a plurality of actuating cylinders and a plurality of actuating piston assemblies, wherein the barrel assembly is arranged between the blowout prevention box and a wellhead, the continuous oil pipe penetrates through the barrel assembly and stretches into the underground, the slip assembly is positioned in the barrel assembly and sleeved outside the continuous oil pipe, the actuating cylinders are uniformly arranged on the outer side part of the barrel assembly along the circumferential direction, the actuating piston assemblies are movably inserted into the actuating cylinders in a one-to-one correspondence mode, and extend into the barrel assembly and are movably connected to the slip assembly respectively. The linkage mechanism is in communication with the trigger cylinder and the actuating cylinder, and the compressed air is capable of controlling the actuating piston assembly to act to change the inner diameter of the slip assembly. That is, when this coiled tubing fracture whereabouts, compressed air can get into the execution cylinder from the air feed subassembly through trigger cylinder and link gear, lets in the position of execution cylinder and then produces pressure to executing piston subassembly through this compressed air, makes its action, and then drives slip subassembly action, makes its clamp coiled tubing, prevents that it from continuing to drop.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following description will briefly explain the drawings needed in the description of the embodiments of the present invention, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to the contents of the embodiments of the present invention and these drawings without inventive effort for those skilled in the art.

FIG. 1 is a schematic view of a well-drop prevention device according to an embodiment of the present invention;

FIG. 2 is an enlarged view of the structure labeled B in FIG. 1;

FIG. 3 is an enlarged view of the structure labeled C in FIG. 1;

Fig. 4 is a cross-sectional view taken along A-A in fig. 1.

In the figure:

10. A blowout prevention box; 20. a coiled tubing;

100. A trigger mechanism; 110. triggering a cylinder; 111. an air inlet interface; 112. an exhaust interface; 120. triggering a piston assembly; 121. triggering a piston; 122. triggering a piston rod; 123. a ventilation ring groove; 124. a first seal ring; 125. a second seal ring; 126. a third seal ring; 127. a pin shaft; 130. a gas supply assembly; 131. a gas supply valve; 140. triggering the elastic element;

200. An actuator; 210. a barrel assembly; 211. a cylinder body; 212. a base; 220. a slip assembly; 230. an execution cylinder; 231. an inboard interface; 232. an outboard interface; 233. executing a cylinder body; 234. executing a cylinder seat; 235. executing a cylinder head; 236. a first buffer tank; 237. a second buffer tank; 240. executing a piston assembly; 241. an actuator piston; 242. executing a piston rod; 243. a slip connecting rod; 250. executing an elastic element;

300. A linkage mechanism; 310. a reversing valve; 320. and a vent valve.

Detailed Description

The invention is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present invention are shown in the drawings.

In the description of the present invention, unless explicitly stated and limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", "left", and the like are orientation or positional relationships based on those shown in the drawings, merely for convenience of description and simplicity of operation, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the invention. Furthermore, the terms "first," "second," and the like, are used merely for distinguishing between descriptions and not for distinguishing between them.

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

FIG. 1 shows a schematic diagram of a well-drop prevention device according to an embodiment of the present invention; FIG. 2 shows an enlarged view of the structure labeled B in FIG. 1; FIG. 3 shows an enlarged view of the structure labeled C in FIG. 1; fig. 4 shows a cross-sectional view in the direction A-A of fig. 1. Referring to fig. 1-4, the present embodiment provides a well-drop prevention device. The well-drop prevention device includes a trigger mechanism 100, an actuator 200, and a linkage mechanism 300. The trigger mechanism 100 is used to perform a reaction operation in time when the coiled tubing 20 breaks. The actuator 200 is used to clamp the coiled tubing 20 after the trigger 100 has reacted to prevent it from continuing to drop to plug the well. The linkage mechanism 300 is communicated between the trigger mechanism 100 and the actuator 200, and can realize linkage of the trigger mechanism 100 and the actuator 200.

Specifically, referring to fig. 1 and 2, the trigger mechanism 100 includes a trigger cylinder 110, a trigger piston assembly 120, an air supply assembly 130, and a trigger spring 140. The trigger cylinder 110 is mounted on the blowout prevention box 10, the trigger piston assembly 120 is movably inserted into the trigger cylinder 110 and extends into the blowout prevention box 10 to abut against the coiled tubing 20, the trigger piston assembly 120 acts to drive the air supply assembly 130 to selectively communicate with the trigger cylinder 110, and the air supply assembly 130 is configured to supply compressed air to the trigger cylinder 110. The trigger elastic member 140 is interposed between an inner wall of an end of the trigger cylinder 110 remote from the blowout preventer 10 and a portion of the trigger piston assembly 120.

Still more specifically, the trigger piston assembly 120 includes a trigger piston 121 and a trigger piston rod 122. The trigger piston rod 122 is coaxially and fixedly connected to the trigger piston 121, and the trigger elastic element 140 is clamped between the inner wall of the end of the trigger cylinder 110, which is far away from the blowout preventer 10, and the trigger piston 121, so that the trigger piston rod 122 can be abutted against the coiled tubing 20.

More specifically, the relative positions of the peripheral portion of the trigger cylinder 110 are respectively provided with an air inlet port 111 and an air outlet port 112, and the air supply assembly 130 is communicated with the air inlet port 111. A vent ring groove 123 is formed around the circumferential side of the trigger piston 121, the trigger piston 121 approaches the blowout prevention box 10 along the length direction of the trigger cylinder 110, and the air inlet port 111, the air outlet port 112 and the vent ring groove 123 are communicated.

More specifically, the trigger piston assembly 120 further includes a first seal 124, a second seal 125, and a third seal 126. The first sealing ring 124, the second sealing ring 125 and the third sealing ring 126 are disposed on the triggering piston 121 along the length direction of the triggering piston 121 in a spacing ring manner, the first sealing ring 124 and the second sealing ring 125 are disposed on two sides of the ventilation ring groove 123 respectively, and when the triggering piston rod 122 abuts against the coiled tubing 20, the third sealing ring 126 and the second sealing ring 125 are disposed on two sides of the air inlet port 111 respectively. The first sealing ring 124, the second sealing ring 125 and the third sealing ring 126 can prevent the compressed air from overflowing to the rest positions in the trigger cylinder 110, form thrust to the trigger piston assembly 120, interfere with the communication effect of the air inlet port 111, the air outlet port 112 and the ventilation ring groove 123, and cause the problem that the trigger mechanism 100 cannot feed back in time when the coiled tubing 20 breaks and falls down.

With continued reference to fig. 2, the firing cylinder 110 includes a firing cylinder body, a firing cylinder block, and a firing cylinder head. The trigger cylinder seat is fixedly connected to the side part of the blowout prevention box 10, the trigger cylinder body is connected to the trigger cylinder seat, and the trigger cylinder cover is buckled on the end part of the trigger cylinder body, which is far away from the trigger cylinder seat, back of the trigger cylinder body. The trigger piston 121 is disposed in the trigger cylinder body, and both ends of the trigger piston rod 122 penetrate the trigger cylinder block and the trigger cylinder head, respectively.

Specifically, the trigger piston rod 122 is provided with a plurality of pin holes through a portion of the trigger cylinder head. A plurality of pin holes are formed at intervals along the length direction of the trigger piston rod 122, and the forming direction of the pin holes is along the radial direction of the trigger piston rod 122. The pin shaft holes are configured to be inserted with pin shafts 127, and the pin shafts 127 can be inserted into a preset positioning structure and any pin shaft hole to realize positioning of the trigger piston rod 122. With the above arrangement, positioning of the trigger piston rod 122 in different positions can be achieved. During normal lowering of the coiled tubing 20, the trigger piston rod 122 is pulled to the limit position in a direction away from the blowout preventer 10 and locked by the pin shaft 127, preventing the trigger piston rod 122 from contacting the coiled tubing 20 at this time, preventing normal lowering of the coiled tubing 20.

Alternatively, in the present embodiment, the air supply assembly 130 may be an air tank in the prior art, and the air supply valve 131 is disposed at the outlet of the air tank. The air supply valve 131 is used to control the on-off of the air supply assembly 130 and the air inlet port 111.

Referring to fig. 1 and 3, the actuator 200 includes a cylinder assembly 210, a slip assembly 220, a plurality of actuating cylinders 230 and a plurality of actuating piston assemblies 240, wherein the cylinder assembly 210 is disposed between the blowout preventer 10 and a wellhead, the coiled tubing 20 extends into the well through the cylinder assembly 210, the slip assembly 220 is disposed in the cylinder assembly 210 and sleeved outside the coiled tubing 20, the actuating cylinders 230 are uniformly disposed at the outer side of the cylinder assembly 210 along the circumferential direction, and the actuating piston assemblies 240 are movably inserted into the actuating cylinders 230 in a one-to-one correspondence manner and extend into the cylinder assembly 210 to be movably connected to the slip assembly 220. The slip assembly 220 is capable of gripping or releasing the coiled tubing 20 by actuation of a plurality of actuator piston assemblies 240.

Specifically, the actuator piston assembly 240 includes an actuator piston 241, an actuator piston rod 242, and a slip connection rod 243. The actuating piston rod 242 is coaxially and fixedly connected to the actuating piston 241, one end of the actuating piston rod 242 extends into the cylinder assembly 210, and two ends of the slip connecting rod 243 are respectively hinged to the end of the actuating piston rod 242 extending into the cylinder assembly 210 and a portion of the slip assembly 220. The actuator piston 241 approaches the barrel assembly 210 and the slip assembly 220 tapers away from the actuator cylinder 230 along the length of the coiled tubing 20, with the slip assembly 220 having a reduced inner diameter. The actuator piston 241 moves away from the barrel assembly 210 and the slip assembly 220 moves progressively closer to the actuator cylinder 230 along the length of the coiled tubing 20, the inner diameter of the slip assembly 220 increasing.

Still more specifically, the implement cylinder 230 includes an implement cylinder body 233, an implement cylinder block 234, and an implement cylinder head 235. The actuating cylinder block 234 is mounted on the cylinder assembly 210, the actuating cylinder body 233 is mounted on the actuating cylinder block 234, and the actuating cylinder head 235 is fastened to an end of the actuating cylinder body 233 remote from the actuating cylinder block 234. The actuating piston 241 is disposed in the actuating cylinder body 233, and one end of the actuating piston rod 242 extends through the actuating cylinder block 234 and into the barrel assembly 210.

More specifically, the actuating cylinder block 234 has a first buffer slot 236 on a side facing the actuating piston 241, the actuating cylinder head 235 has a second buffer slot 237 on a side facing the actuating piston 241, and the two ends of the actuating piston 241 are respectively provided with a first boss structure and a second boss structure. The first buffer slot 236 matches the shape of the first boss structure, and the two can be in clearance fit; the shape of the second buffer groove 237 matches the shape of the second boss structure, and the two can be clearance fit. The first buffer groove 236 and the second buffer groove 237 can provide a buffer function to the execution piston 241.

More specifically, the inside interface 231 and the outside interface 232 are provided at intervals along the length direction of the actuating cylinder 230. The inner interface 231 and the outer interface 232 are selectively coupled to the exhaust interface 112 via the linkage 300. The actuating piston 241 is located between the inner interface 231 and the outer interface 232, and the air pressure difference between the inner interface 231 and the outer interface 232 can drive the actuating piston 241 to move along the length direction of the actuating cylinder 230.

Preferably, the actuator 200 further comprises an actuator spring 250, the actuator spring 250 being sandwiched between the actuator cylinder block 234 and the actuator piston 241 and being configured to urge the actuator piston 241 away from the actuator cylinder block 234. The actuator spring 250 acts to reset the actuator piston 241 in a natural state adjacent the actuator cylinder head 235, thereby allowing the slip assembly 220 to lift and relax and preventing the slip assembly 220 from holding the coiled tubing 20.

Referring to fig. 1 and 4, the slip assembly 220 includes a plurality of slips uniformly disposed circumferentially about the coiled tubing 20, each set of the actuator cylinder 230 and actuator piston assembly 240 being capable of moving one of the slips along the length of the coiled tubing 20. In this embodiment, four slips are specifically provided. The four slips enclose an oil pipe receiving space through which the coiled tubing 20 extends.

Specifically, the cartridge assembly 210 includes a cartridge body 211 and a base 212. The cylinder body 211 is disposed outside the wellhead of the well, and the base 212 is disposed inside the bottom of the cylinder body 211. The actuating cylinder 230 is mounted on the upper side of the lateral portion of the cylinder body 211, the base 212 is provided with a guiding through hole, the wall of the guiding through hole gradually approaches the central axis of the base 212 along the length direction of the coiled tubing 20, and a plurality of slips respectively prop against the inner wall of the guiding through hole. As the slips move progressively farther from the actuator cylinder 230 along the length of the coiled tubing 20, the slips move closer to each other until they are clamped against the coiled tubing 20.

Referring to fig. 1, the linkage 300 is disposed between the trigger cylinder 110 and the actuating cylinder 230. The linkage mechanism 300 comprises a reversing valve 310 and a vent valve 320, wherein the reversing valve 310 controls the vent valve 320 to be communicated with the inner side interface 231, and the outer side interface 232 is communicated with the exhaust interface 112; alternatively, the reversing valve 310 controls the vent valve 320 to communicate with the outer port 232 and the inner port 231 to communicate with the exhaust port 112. The linkage 300 controls the actuation of the actuator piston assembly 240 to vary the inside diameter of the slip assembly 220 by delivering compressed air to different positions of the actuator cylinder 230 to create different directional thrust forces on the actuator piston 241. The reversing valve 310 is a two-position four-way reversing valve, and adopts manual reversing.

The working principle of the well-drop prevention device provided by the embodiment is as follows:

The outside port 232 is connected to the exhaust port 112 and the vent valve 320 is connected to the inside port 231 by the control of the reversing valve 310, and the well-drop preventing device is in operation. When the coiled tubing 20 breaks, the abutting action of the coiled tubing 20 on the trigger piston rod 122 is eliminated, and the trigger piston 121 gradually approaches the blowout prevention box 10 under the pushing of the trigger elastic element 140 until the exhaust port 112 is opposite to the ventilation ring groove 123, and at this time, the exhaust port 112 is communicated with the air inlet port 111. At this time, compressed air can enter the execution cylinder 230 from the outer interface 232, and thrust is formed on the execution piston 241, so that the execution piston 241 moves towards the direction approaching the barrel assembly 210, and the slip connecting rod 243 is driven to push the slip assembly 220 to move towards the direction away from the blowout prevention box 10, and under the limitation of the shape of the inner wall of the guide through hole, the distance between the slips is gradually reduced until the coiled tubing 20 is clamped, and the continuous falling along the oil well is prevented.

The reversing valve 310 is used to reverse the direction, so that the vent valve 320 is connected to the outer port 232, the inner port 231 is connected to the exhaust port 112, and the anti-drop device is in a non-working state. Compressed air can enter the execution cylinder 230 from the inner interface 231 to push the execution piston 241, so that the execution piston 241 moves towards a direction far away from the cylinder assembly 210, and the slip connecting rod 243 is driven to pull the slip assembly 220 to move towards a direction close to the blowout prevention box 10, the distances among a plurality of slips are gradually increased, and the position of the trigger piston 121 is reset, so that the anti-drop well device is restored to an original state.

It is to be understood that the above examples of the present invention are provided for clarity of illustration only and are not limiting of the embodiments of the present invention. Various obvious changes, rearrangements and substitutions can be made by those skilled in the art without departing from the scope of the invention. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the invention are desired to be protected by the following claims.

Claims (10)

1. Anti-lost device, its characterized in that includes:

the trigger mechanism (100), the trigger mechanism (100) comprises a trigger cylinder (110), a trigger piston assembly (120) and an air supply assembly (130), the trigger cylinder (110) is installed on the blowout prevention box (10), the trigger piston assembly (120) is movably inserted into the trigger cylinder (110) and stretches into the blowout prevention box (10) to abut against the continuous oil pipe (20), the trigger piston assembly (120) acts to drive the air supply assembly (130) to selectively communicate with the trigger cylinder (110), and the air supply assembly (130) is configured to provide compressed air for the trigger cylinder (110);

The actuating mechanism (200), actuating mechanism (200) include barrel subassembly (210), slips subassembly (220), a plurality of actuating cylinder (230) and a plurality of actuating piston subassembly (240), barrel subassembly (210) set up in prevent spouting between box (10) and the well head, coiled tubing (20) run through barrel subassembly (210) stretches into underground, slips subassembly (220) are located in barrel subassembly (210), the cover is located outside coiled tubing (20), a plurality of actuating cylinder (230) set up evenly in along circumference in the lateral part of barrel subassembly (210), a plurality of actuating piston subassembly (240) one-to-one respectively movable insert locate a plurality of actuating cylinder (230), and stretch into barrel subassembly (210), swing joint respectively in slips subassembly (220);

And the linkage mechanism (300) is communicated with the trigger cylinder (110) and the execution cylinder (230), and the compressed air can control the execution piston assembly (240) to act so as to change the inner diameter of the slip assembly (220).

2. The well drop prevention device according to claim 1, wherein the trigger piston assembly (120) comprises a trigger piston (121) and a trigger piston rod (122), the trigger piston rod (122) is coaxially and fixedly connected to the trigger piston (121), the trigger mechanism (100) further comprises a trigger elastic element (140), and the trigger elastic element (140) is clamped between an inner wall of one end of the trigger cylinder (110) far away from the blowout prevention box (10) and the trigger piston (121), so that the trigger piston rod (122) can be abutted against the coiled tubing (20).

3. The well drop prevention device of claim 2, wherein the actuating piston assembly (240) comprises an actuating piston (241), an actuating piston rod (242) and a slip connecting rod (243), the actuating piston rod (242) being coaxially fixedly connected to the actuating piston (241), one end of the actuating piston rod (242) extending into the barrel assembly (210), two ends of the slip connecting rod (243) being hinged to the end of the actuating piston rod (242) extending into the barrel assembly (210) and to a portion of the slip assembly (220), respectively;

The actuating piston (241) is close to the barrel assembly (210), the slip assembly (220) is gradually far away from the actuating cylinder (230) along the length direction of the continuous oil pipe (20), and the inner diameter of the slip assembly (220) is reduced;

The actuating piston (241) is far away from the barrel assembly (210), the slip assembly (220) gradually approaches the actuating cylinder (230) along the length direction of the continuous oil pipe (20), and the inner diameter of the slip assembly (220) is increased.

4. A well drop prevention device according to claim 3, wherein the relative positions of the peripheral parts of the trigger cylinder (110) are respectively provided with an air inlet interface (111) and an air outlet interface (112), and the air supply assembly (130) is communicated with the air inlet interface (111);

An inner side interface (231) and an outer side interface (232) are arranged at intervals along the length direction of the execution cylinder (230), and the inner side interface (231) and the outer side interface (232) are selectively communicated with the exhaust interface (112) through the linkage mechanism (300); the execution piston (241) is located between the inner side interface (231) and the outer side interface (232), and the air pressure difference between the inner side interface (231) and the outer side interface (232) can drive the execution piston (241) to move along the length direction of the execution cylinder (230).

5. The well drop prevention device according to claim 4, wherein a ventilation ring groove (123) is annularly arranged along the peripheral side part of the trigger piston (121), the trigger piston (121) is close to the blowout prevention box (10) along the length direction of the trigger cylinder (110), and the air inlet interface (111), the air outlet interface (112) and the ventilation ring groove (123) are communicated.

6. The well drop prevention device of claim 5, wherein the trigger piston assembly (120) further comprises a first sealing ring (124), a second sealing ring (125) and a third sealing ring (126), the first sealing ring (124), the second sealing ring (125) and the third sealing ring (126) are arranged on the trigger piston (121) along the length direction of the trigger piston (121) in a spacing ring manner, the first sealing ring (124) and the second sealing ring (125) are respectively arranged on two sides of the ventilation ring groove (123), and when the trigger piston rod (122) abuts against the coiled tubing (20), the third sealing ring (126) and the second sealing ring (125) are respectively arranged on two sides of the air inlet interface (111).

7. The well-drop prevention device of claim 4, wherein the linkage (300) comprises a diverter valve (310) and a vent valve (320), the diverter valve (310) controlling the vent valve (320) to communicate with the inner port (231), the outer port (232) communicating with the exhaust port (112); or, the reversing valve (310) controls the ventilation valve (320) to be communicated with the outer side interface (232), and the inner side interface (231) is communicated with the exhaust interface (112).

8. A well drop prevention device according to claim 3, wherein the actuating cylinder (230) comprises an actuating cylinder body (233), an actuating cylinder block (234) and an actuating cylinder head (235), the actuating cylinder block (234) being mounted to the barrel assembly (210), the actuating cylinder body (233) being mounted to the actuating cylinder block (234), the actuating cylinder head (235) being snapped onto an end of the actuating cylinder body (233) remote from the actuating cylinder block (234), the actuating piston (241) being disposed in the actuating cylinder body (233);

The execution cylinder seat (234) is just to one side of execution piston (241) is offered first dashpot (236), execution cylinder head (235) just to one side of execution piston (241) is offered second dashpot (237), the shape of first dashpot (236) with second dashpot (237) matches respectively the shape at execution piston (241) both ends.

9. The well-drop prevention device of claim 8, wherein the actuator (200) further comprises an actuator spring (250), the actuator spring (250) being sandwiched between the actuator cylinder block (234) and the actuator piston (241) and configured to urge the actuator piston (241) away from the actuator cylinder block (234).

10. The well-drop prevention device of claim 1, wherein the slip assembly (220) comprises a plurality of slips uniformly disposed circumferentially about the coiled tubing (20), each set of the actuating cylinder (230) and the actuating piston assembly (240) being capable of moving one of the slips along the length of the coiled tubing (20), respectively;

The cylinder assembly (210) comprises a cylinder body (211) and a base (212), the base (212) is arranged on the inner side of the bottom of the cylinder body (211), the execution cylinder (230) is installed on the upper side of the side part of the cylinder body (211), the base (212) is provided with a guide through hole, the guide through hole is gradually far away from the execution cylinder (230) along the length direction of the continuous oil pipe (20), the hole wall of the guide through hole is gradually close to the central axis of the base (212), and a plurality of slips respectively prop against the inner wall of the guide through hole;

When a plurality of slips gradually move away from the execution cylinder (230) along the length direction of the continuous oil pipe (20), the slips are mutually close until abutting against the continuous oil pipe (20).