A device for preventing pipe string from flying out during pressurized operations

Abstract

This invention discloses a live-line operation prevention device, belonging to the field of live-line operation technology. It solves the problem of safety accidents caused by high-speed tubing ejection due to personnel misoperation, equipment failure, or abnormal wellbore pressure in existing anti-top slip devices. The device includes a segmented housing, a straightening mechanism, and a locking mechanism. The segmented housing is cylindrical, and the tubing is inserted inside. Several sets of straightening and locking mechanisms are arranged in a ring inside the segmented housing, with the tubing located at the center of the straightening and locking mechanisms. In this invention, if the tubing abnormally ascends, the slip teeth are instantly triggered by the elastic force of the locking spring and the upward force of the tubing. The slip teeth bite the tubing, converting the upward force into a radial clamping force, achieving a self-locking effect of "the greater the upward force, the tighter the clamping," thereby intercepting the tubing within the device and preventing high-speed tubing ejection from causing safety accidents.

Description

Technical Field

[0001] This invention relates to the field of live work technology, and in particular to a device for preventing pipe strings from flying out during live work. Background Technology

[0002] Live pressure operation technology, as one of the key technologies for modern oil and gas field development and maintenance, has significant advantages in protecting reservoirs, improving recovery rates, and protecting the environment. However, live pressure operation involves running and pulling tubing in an environment where the wellbore is not under pressure and there is high pressure at the wellhead. Due to the pressure difference between the inside and outside of the well, when the weight of the tubing inside the wellbore is less than the upward force acting on the tubing, the tubing will experience upward pressure.

[0003] Currently, existing technologies use anti-top slips to hold the tubing string in place to prevent it from flying out. However, in cases of human error, slip malfunction, or abnormal wellbore pressure, the anti-top slips may fail to effectively hold the ascending tubing string, easily leading to a "tubing string flyout" safety accident, resulting in serious consequences such as equipment damage, personal injury, and environmental pollution. To completely avoid tubing string flyout accidents, it is necessary to design a device that can prevent tubing string flyout, adding a reliable safety barrier to pressurized operations.

[0004] Therefore, the present invention provides a purely mechanical, rapid-response, safe and reliable device for preventing pipe string from flying out during pressurized operations. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a device to prevent tubing from flying out during pressurized operations. This device solves the problem of safety accidents caused by the tubing flying out at high speed due to personnel misoperation, equipment failure, or abnormal wellbore pressure when using existing anti-top slip devices.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A device for preventing pipe string from flying out during pressurized operations includes a segmented shell, a straightening mechanism, and a locking mechanism. The segmented shell is cylindrical, and the pipe string passes through the interior of the segmented shell. Several sets of straightening and locking mechanisms are provided, and the sets of straightening and locking mechanisms are arranged in a ring inside the segmented shell, with the pipe string located at the center of the straightening and locking mechanisms. The straightening and locking mechanisms clamp the pipe string.

[0007] In this scheme, when the tubing or drill pipe is run into the well, the tubing or drill pipe passes through the holes inside the split shell. The straightening mechanism forces the tubing to be straightened and centered, placing it at the axial position of the split shell. The locking mechanism locks the tubing to prevent it from moving upward and avoids abnormal ejection of the tubing.

[0008] Furthermore, the segmented shell includes a top cover plate, an outer shell, a support plate, and a fastening plate; the outer shell is evenly divided into several sections along its circumference, and these sections are connected by fitting bolts; the top cover plate is circular with a hole in the center, and is divided into the same number of sections as the outer shell along its circumference, with each top cover plate overlapping the two adjacent outer shell sections at both ends of its arc, and bolt holes being provided at both ends of each top cover plate, with the cover plate screws in the bolt holes at both ends being threaded into the cover plate screw holes at the top of the two adjacent outer shell sections; the support plate and the fastening plate are sequentially installed at the bottom of the outer shell.

[0009] In this design, the outer shell is evenly divided into several pieces, which facilitates the assembly and installation of the internal straightening and locking mechanisms; the upper cover plate is set at the splicing seam between two adjacent outer shell pieces to connect the two adjacent outer shell pieces and connect the segmented shells into a whole.

[0010] Furthermore, the locking mechanism includes a body with an arc-shaped cross-section. Several sets of locking mechanism bodies are spliced ​​together circumferentially to form a complete circle. The back of the body is fixed to the inner wall of the outer shell by bolts. The body has a conical cavity inside, and the inner wall of the conical cavity has an inclined first dovetail groove. The first dovetail groove slides in conjunction with the first dovetail wedge at the rear end of the arc-shaped slider. The front end of the arc-shaped slider has a slip tooth for gripping the insertion tubing. The bottom of the body has an inclined spring hole, in which a spring tube is movably installed. A locking spring is installed inside the spring tube. The top of the spring tube is connected to the bottom of the arc-shaped slider. A keyway is also provided on the inner wall of the main body at the top of the first dovetail groove, and a locking block is fixed in the keyway; the locking block limits the stroke of the arc-shaped slider.

[0011] In this design, when tubing or drill pipe is lowered into the well through the holes inside the segmented casing, the straightening mechanism straightens the tubing string. The arc-shaped slider at the front end of the locking mechanism is pushed downwards, compressing the locking spring. The slip teeth at the front end of the arc-shaped slider always grip the tubing string, allowing tubing strings of various sizes or other tools to be lowered freely. If the tubing string in the well tends to eject upwards due to excessive pressure, the spring force of the locking spring pushes the arc-shaped slider upwards along the first dovetail groove. Simultaneously, several annularly distributed arc-shaped sliders converge towards the center, rapidly reducing the diameter of the near-circle formed by the arc-shaped sliders. The slip teeth at the front end of the arc-shaped sliders grip the outer wall of the tubing string, preventing it from moving upwards. The greater the upward force of the tubing string, the stronger the grip of the slip teeth on the outer wall, thus preventing abnormal upward movement of the tubing string.

[0012] Furthermore, the back of the body connected to the outer shell is provided with several protrusions, and a groove is formed between two adjacent protrusions; several toothed retaining rings are provided on the inner wall of the outer shell, and a toothed groove is formed between two adjacent toothed retaining rings along the axial direction; each toothed retaining ring is correspondingly embedded in each groove, and each protrusion is correspondingly embedded in each toothed groove; each protrusion is provided with a locking screw hole, and a locking through hole is provided in each toothed groove at the position corresponding to the locking screw hole. The locking screw passes through the locking through hole and is threaded into the locking screw hole to fix the body.

[0013] In this solution, during installation, the boss on the main body is rotated to the lower part of the dental clamp retaining ring, i.e., into the dental clamp groove, to prevent it from moving upward; then, the boss is fastened to the inside of the dental clamp groove by the locking screw, ensuring stability and reliability after installation.

[0014] Furthermore, the straightening mechanism includes a square housing. One end of the square housing is fitted with a second dovetail wedge via a connecting screw. The second dovetail wedge is slidably disposed within a second dovetail groove axially opened on the inner wall of the housing. The other end of the square housing is open, and an outer cavity is movably disposed within the opening. The outer cavity has a tapered cross-section, and an inner cavity is fixedly installed within the outer cavity. A first spring groove is provided on the inner side of the second dovetail wedge, and a second spring groove is provided on the inner side of the outer cavity. A straightening spring is installed between the first spring groove and the second spring groove. The end of the inner cavity near the axis abuts against the tubing to straighten the tubing.

[0015] In this design, the outer cavity and the inner cavity can move back and forth along the square shell, while compressing the straightening spring; under the elastic force of the straightening spring, the end of the inner cavity straightens the tubing.

[0016] Furthermore, the outer cavity has an outer groove for steel balls at its end, and the inner cavity has an inner groove for steel balls at its end; a spherical cavity is formed between the outer groove and the inner groove, and steel balls are movably disposed within the spherical cavity; the outer wall of the steel balls rolls on the tubular column.

[0017] In this design, when it is necessary to run tubing or drill pipe and other tools into the well, the steel balls are pushed backward, causing the inner and outer cavities to move backward and compressing the centering spring. The reaction force of the centering spring forces the tubing and tools to be centered, thus achieving a centering effect. By utilizing the contact between the steel balls and the tubing, the steel balls roll along the surface of the tubing during the centering process, reducing the friction between them.

[0018] Furthermore, the square shell is in the shape of a square cavity. The end of the square shell that connects to the second dovetail wedge has four connecting screw holes. Each of the four corners of the second dovetail wedge has a connecting through hole. The connecting screw passes through the connecting through hole and is threaded onto the connecting screw hole, connecting the second dovetail wedge and the square shell into a whole.

[0019] Furthermore, the bottom of the outer shell has a section with a reduced diameter. Each outer shell has two supporting ribs on its outer wall at the reduced diameter section. Each supporting rib has a connecting through hole. The two supporting ribs on adjacent outer shells are connected by connecting bolts that pass through the connecting through hole.

[0020] In this solution, the supporting ribs at the bottom of two adjacent outer shells are connected using combination bolts, and the splicing seams at the top of two adjacent outer shells are connected using a top cover plate, so that multiple outer shells are spliced ​​into a whole.

[0021] Furthermore, the bottom of the outer casing is supported on the plate of the fixed slip assembly of the live-line working machine; the flange base at the bottom of the outer casing is provided with annularly distributed base through holes; The upper plate of the fixed clamp assembly is a triangular plate; the support plate is divided into three pieces, and the three support plates abut against the three sides of the upper plate of the fixed clamp assembly respectively. Each support plate has three bolt holes. The fastening plate abuts against the bottom of the plate on the fixing clamp assembly; the fastening plate is circular in shape with a hole in the middle, and the fastening plate is divided into three parts along the circumference, with three bolt holes on each fastening plate; The fastening bolts pass through the base through hole on the flange base, the bolt hole at the bottom of the support plate, and the bolt hole at the bottom of the fastening plate in sequence to fasten the outer shell, support plate, and fastening plate.

[0022] In this solution, the support plate fixes the upper plate of the triangular fixed slip assembly through its external structure. The support plate and the upper plate of the fixed slip assembly are confined to the same plane. The flange base and fastening plate at the bottom of the outer shell clamp the support plate and the upper plate of the fixed slip assembly from the top and bottom to form a whole and prevent displacement. At the same time, the entire anti-pipeline flying device for live working is fixed to the upper plate of the fixed slip assembly of the live working machine.

[0023] Furthermore, the outer shell is divided into three parts along the circumference, with six sets of straightening and locking mechanisms each; two sets of straightening mechanisms and two sets of locking mechanisms are fixed inside each outer shell.

[0024] The beneficial effects of this invention are: This invention provides a live-line operation anti-spill device, the core of which lies in the use of a purely mechanical self-locking principle: During normal operation, the arc-shaped slider slides along the inclined first dovetail groove, and as the pipe string descends, it drives the arc-shaped slider and the slip teeth to overcome the preload of the locking spring and move downwards; once the pipe string abnormally rises, the slip teeth are instantly triggered under the combined action of the locking spring's elasticity and the upward force of the pipe string, and the slip teeth bite into the pipe string, converting the upward force of the pipe string into a radial biting force, achieving a self-locking effect of "the greater the upward force, the tighter the bite," thereby reliably intercepting the pipe string within the device. This solves the technical problem of existing anti-spill slips causing safety accidents due to high-speed pipe string ejection caused by personnel misoperation, equipment failure, or abnormal wellbore pressure, providing an efficient and passive safety barrier for live-line operations.

[0025] The entire live-line anti-spike ejection device relies on a purely mechanical self-locking principle, requiring no external power, sensors, or control systems. It features a simple structure, high reliability, and no risks of power failure or false alarms. It offers rapid response and reliable braking. From the moment the string ascends to the moment the slips complete braking, the entire process is completed within milliseconds, far exceeding the reaction speed of manual operation and hydraulic systems. Its simple structure results in lower manufacturing and maintenance costs compared to complex electro-hydraulic control systems, making it easy to deploy and implement in oil and gas fields. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the downward movement of the tubing in a pressurized operation anti-spraying device according to the present invention; Figure 2 This is a schematic diagram of the upward movement of the tubing in a pressurized operation anti-spandrel device of the present invention; Figure 3 This is a schematic diagram of the disassembled structure of the segmented shell in this invention; Figure 4 for Figure 3 Schematic diagram of section AA; Figure 5 for Figure 3 Schematic diagram of the structure of section BB; Figure 6 for Figure 3 Schematic diagram of the CC section; Figure 7 This is a schematic diagram of the structure of the support plate and the fixed clamp assembly of the plate plate in this invention; Figure 8 This is a schematic diagram of the disassembled locking mechanism in this invention; Figure 9 This is a schematic diagram of the cross-sectional structure of the locking mechanism in this invention; Figure 10 This is a side view of the straightening mechanism in this invention; Figure 11This is a top view of the straightening mechanism in this invention; Figure 12 This is a partial cross-sectional view of a device for preventing pipe string from flying out during pressurized operations according to the present invention; Figure 13 for Figure 11 Schematic diagram of the structure of section DD; Figure 14 for Figure 11 Schematic diagram of the EE section; Figure 15 for Figure 11 A schematic diagram of the FF section.

[0027] Figure label: 1. Split shell; 2. Alignment mechanism; 3. Locking mechanism; 11. Top cover plate; 12. Outer shell; 13. Support plate; 14. Fastening plate; 121. Cover plate screw hole; 122. Second dovetail groove; 123. Toothed retaining ring; 124. Toothed groove; 125. Locking through hole; 126. Support rib plate; 127. Assembly through hole; 128. Flange base; 129. Base through hole; 151. Cover plate screw; 152. Locking screw; 153. Assembly bolt; 154. Fastening bolt; 201. Second dovetail wedge; 202. First spring groove; 203. 204. Connecting through hole; 205. Connecting screw; 206. Straightening spring; 207. Square shell; 208. Connecting screw hole; 209. Outer cavity; 210. Steel ball; 211. Inner cavity; 212. Second spring groove; 301. Body; 302. Groove; 303. Boss; 304. Locking screw hole; 305. Locking block; 306. Keyway; 307. Arc-shaped slider; 308. Locking tooth; 309. First dovetail wedge; 310. Spring tube; 311. Locking spring; 312. First dovetail groove; 313. Spring hole; 4. Fixed locking plate. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Specific embodiments of the present invention are described below to facilitate understanding by those skilled in the art. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various modifications are obvious as long as they fall within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0029] like Figure 1 and Figure 2 As shown, this embodiment provides a device to prevent tubing from flying out during pressurized operations, solving the problem of safety accidents caused by the tubing flying out at high speed due to personnel misoperation, equipment failure, or abnormal wellbore pressure in existing anti-top slip devices; specifically, it includes: The components include a split housing 1, a straightening mechanism 2, and a locking mechanism 3; The split housing 1 is cylindrical, and the tubing string passes through its interior. Several sets of centering mechanisms 2 and locking mechanisms 3 are arranged in a ring inside the split housing 1, with the tubing string positioned at the center of these mechanisms. The centering and locking mechanisms 2 and 3 clamp the tubing string. When tubing or drill pipe is inserted into the well, it passes through the holes inside the split housing 1. The centering mechanism 2 forcibly centers the tubing string, placing it at the axial position of the split housing 1. The locking mechanism 3 locks the tubing string, preventing it from moving upwards and avoiding abnormal ejection.

[0030] The structure of the segmented shell 1 is as follows: like Figure 3 As shown, the segmented shell 1 includes an upper cover plate 11, an outer shell 12, a support plate 13, and a fastening plate 14; the outer shell 12 is evenly divided into several pieces along the circumferential surface, and the several pieces of the outer shell 12 are connected by a combination bolt 153.

[0031] The upper cover plate 11 is circular with a hole in the center. The upper cover plate 11 is divided into the same number of sections as the outer shell 12 along its circumference. Each upper cover plate 11 overlaps two adjacent outer shell sections 12 at its two ends along its arc. Bolt holes are provided at both ends of each upper cover plate 11, and cover plate screws 151 in these holes are threaded into the cover plate screw holes 121 at the top of the two adjacent outer shell sections 12. The support plate 13 and fastening plate 14 are sequentially installed at the bottom of the outer shell 12. The outer shell 12 is evenly divided into several sections to facilitate the assembly and installation of the internal straightening mechanism 2 and locking mechanism 3.

[0032] The bottom of the outer shell 12 has a narrowed section, and each outer shell 12 has two supporting ribs 126 on its outer wall at the narrowed section. Figure 6 As shown, each supporting rib plate 126 has a connecting through hole 127. Two adjacent supporting rib plates 126 on two adjacent outer shells 12 are connected by connecting bolts 153 passing through the connecting through holes 127. The supporting rib plates 126 at the bottom of two adjacent outer shells 12 are connected by connecting bolts 153, and the splicing seam at the top of two adjacent outer shells 12 is connected by the top cover plate 11, so that multiple outer shells 12 are spliced ​​into a whole.

[0033] like Figure 7As shown, the bottom of the outer casing 12 is supported on the upper plate 4 of the fixed slip assembly of the live-line working machine; the flange base 128 at the bottom of the outer casing 12 has annularly distributed base through holes 129. The upper plate 4 of the fixed slip assembly is a triangular plate; the support plate 13 is divided into three parts, and the three support plates 13 respectively abut against the three sides of the upper plate 4 of the fixed slip assembly, and each support plate 13 has three bolt holes.

[0034] The fastening plate 14 abuts against the bottom of the plate 4 on the fixed clamp assembly. The fastening plate 14 is circular with a hole in the middle, and is divided into three parts along the circumference. Each fastening plate 14 has three bolt holes. The fastening bolts 154 pass through the base through hole 129 on the flange base 128, the bolt holes at the bottom of the support plate 13, and the bolt holes at the bottom of the fastening plate 14 in sequence, to fasten the outer shell 12, the support plate 13, and the fastening plate 14.

[0035] The support plate 13 fixes the upper plate 4 of the triangular fixed slip assembly through its external structure. The support plate 13 and the upper plate 4 of the fixed slip assembly are confined to the same plane. The flange base 128 and the fastening plate 14 at the bottom of the outer shell 12 clamp the support plate 13 and the upper plate 4 of the fixed slip assembly from the top and bottom to form a whole and prevent displacement. At the same time, the entire anti-pipe-flying device for live working is fixed to the upper plate 4 of the fixed slip assembly of the live working machine.

[0036] The structure of locking mechanism 3 is as follows: like Figure 8 As shown, the locking mechanism 3 includes a body 301, a boss 303, an arc-shaped slider 307, a first dovetail wedge 309, a locking tooth 308, a spring tube 310, a locking spring 311, and a locking block 305. The cross-section of the body 301 is arc-shaped, and several sets of the bodies 301 of the locking mechanism 3 are spliced ​​together circumferentially to form a complete circle. The back of the body 301 is fixed to the inner wall of the outer shell 12 by bolts. The body 301 has a conical cavity inside, and the inner wall of the conical cavity has an oblique first dovetail groove 312. The first dovetail groove 312 slides with the first dovetail wedge 309 at the rear end of the arc-shaped slider 307, allowing the arc-shaped slider 307 to move up and down. Figure 9 As shown. The front end of the arc-shaped slider 307 is a slip tooth 308, which is used to clamp the tubing or drill pipe and other well access strings and tools. A spring hole 313 is obliquely provided at the bottom of the body 301. A spring tube 310 is movably installed in the spring hole 313, and a locking spring 311 is provided inside the spring tube 310. The top of the spring tube 310 is connected to the bottom of the arc-shaped slider 307. A keyway 306 is also provided on the inner wall of the body 301 at the top of the first dovetail groove 312. A locking block 305 is fixed in the keyway 306. The locking block 305 limits the stroke of the arc-shaped slider 307 to prevent the arc-shaped slider 307 from coming off upward.

[0037] When tubing or drill pipe is lowered into the well through the holes inside the split housing 1, the straightening mechanism 2 straightens the tubing. The arc-shaped slider 307 at the front end of the locking mechanism 3 is pushed downward, the locking spring 311 is compressed, and the slip teeth 308 at the front end of the arc-shaped slider 307 always grip the tubing, allowing tubing of various sizes or other tools to be lowered freely. If the tubing in the well tends to eject upward due to excessive pressure, the spring force of the locking spring 311 can push the arc-shaped slider 307 to slide upward along the first dovetail groove 312. At the same time, several annularly distributed arc-shaped sliders 307 converge towards the center, and the diameter of the circle formed by the arc-shaped sliders 307 rapidly decreases. The slip teeth 308 at the front end of the arc-shaped slider 307 grip the outer wall of the tubing, preventing it from moving upward. The greater the upward force of the tubing, the greater the force of the slip teeth 308 gripping the outer wall of the tubing, thus preventing abnormal upward movement of the tubing.

[0038] Specifically, the back of the main body 301, which connects to the outer shell 12, is provided with several protrusions 303, and a groove 302 is formed between two adjacent protrusions 303. For example... Figure 5 As shown, a plurality of toothed retaining rings 123 are provided on the inner wall of the outer casing 12, and a toothed groove 124 is formed between two adjacent toothed retaining rings 123 along the axial direction; each toothed retaining ring 123 is correspondingly embedded in each groove 302, and each corresponding boss 303 is correspondingly embedded in each toothed groove 124; each boss 303 is provided with a locking screw hole 304, and a locking through hole 125 is provided in each toothed groove 124 at a position corresponding to the locking screw hole 304, and a locking screw 152 passes through the locking through hole 125 and is threaded into the locking screw hole 304 to fix the body 301.

[0039] As a preferred embodiment, the outer shell 12 can be evenly divided into three pieces along its circumference. Each piece has the same structure and size. Each outer shell 12 contains two toothed retaining rings 123. The six toothed retaining rings 123 have six gaps on each plane. During installation, the boss 303 on the main body 301 is rotated 60° to the lower part of the toothed retaining ring 123, i.e., inside the toothed groove 124, to prevent it from moving upward. Then, the boss 303 is fastened to the inside of the toothed groove 124 by the locking screw 152. After installation, it is stable and reliable.

[0040] The structure of the straightening mechanism 2 is as follows: like Figure 10 and Figure 11 As shown, the straightening mechanism 2 includes a square housing 206, a connecting screw 204, a second dovetail wedge 201, an outer cavity 208, an inner cavity 210, a straightening spring 205, and a steel ball 209. The second dovetail wedge 201 is mounted on one end of the square housing 206 via the connecting screw 204. Figure 4As shown, a second dovetail groove 122 is axially formed on the inner wall of the outer shell 12, and a second dovetail wedge 201 is slidably disposed within the second dovetail groove 122. The other end of the square shell 206 is open, and an outer cavity 208 is movably disposed within the opening. The outer cavity 208 has a tapered cross-section, and an inner cavity 210 is fixedly installed within the outer cavity 208. A first spring groove 202 is provided on the inner side of the second dovetail wedge 201, and 18 second spring grooves 211 are formed on the inner side of the inner cavity 210. A straightening spring 205 is installed between the first spring groove 202 and the second spring groove 211 to prevent the straightening spring 205 from shifting. The end of the inner cavity 210 near the axis abuts against the tubing to straighten the tubing.

[0041] The outer cavity 208 has an outer groove for steel balls 209 at its end, and the inner cavity 210 has an inner groove for steel balls 209 at its end. A spherical cavity is formed between the outer groove and the inner groove of the steel balls 209, and the steel balls 209 are movably disposed within the spherical cavity. The outer wall of the steel balls 209 rolls on the tubing string. When it is necessary to run tubing or drill pipe and other tools into the well, the steel balls 209 are squeezed backward, pushing the inner cavity 210 and the outer cavity 208 backward, and compressing the centering spring 205. The reaction force of the centering spring 205 forces the tubing string and tools to be forcibly centered, thus achieving a centering effect. By utilizing the contact between the steel balls 209 and the tubing string, the steel balls 209 roll along the surface of the tubing string during the centering process, reducing the friction between them.

[0042] The square housing 206 has a square cavity shape. Four connecting screw holes 207 are provided at one end of the square housing 206 that connects to the second dovetail wedge 201. Each of the four corners of the second dovetail wedge 201 is provided with a connecting through hole 203. The connecting screw 204 passes through the connecting through hole 203 and is threaded onto the connecting screw hole 207, connecting the second dovetail wedge 201 and the square housing 206 into a whole.

[0043] In a preferred embodiment, the outer shell 12 is divided into three parts along its circumferential surface, and the straightening mechanism 2 and the locking mechanism 3 are each provided with six sets, such as... Figures 12-15 As shown. Each outer shell 12 has two sets of straightening mechanisms 2 and two sets of locking mechanisms fixed inside.

[0044] The working principle of this embodiment is as follows: During normal pressurized tubing lowering operations, tubing or drill pipe is lowered into the well through the holes inside the split housing 1. At this time, the downward direction of the tubing is consistent with the downward movement of the slip 308, which allows the slip 308 to overcome the preload of the locking spring 311 and push the slip 308 outward, enabling it to "open" around the hinge axis. This process does not hinder the downward movement of the tubing and does not interfere with normal well lowering operations.

[0045] When the anti-top slip of the live working machine fails or due to operator error, and the tubing string begins to rise abnormally under the influence of high-pressure fluid in the well, the live working machine anti-tubing-out device will perform the following actions: Instantaneous triggering: Once the column begins to move upward, its upward movement causes the locking teeth 308 and the arc-shaped slider 307 to move upward. At the same time, with the assistance of the elastic force of the locking spring 311, the locking teeth 308 retract inward and instantly bite the column body 301.

[0046] Self-locking effect: After engagement occurs, the continued upward movement of the tubing applies an upward frictional force to the locking teeth 308. This upward frictional force is converted into a torque that further "weaves" the locking teeth 308 inward. The greater the upward force on the tubing, the stronger the wedging torque, and the tighter the engagement of the locking teeth 308 with the tubing, thus achieving the self-locking effect of "the greater the upward force, the tighter the engagement," until the upward force on the tubing disappears.

[0047] Reliable load bearing: Ultimately, all the upward force is transmitted to the body 301 through the locked jaws 308, and is finally borne by the high-strength split shell 1, thereby firmly locking the high-speed flying tube into the split shell 1 and effectively preventing the tube from flying out.

[0048] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention and should be understood as not limiting the scope of protection of the invention to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed herein without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of the invention.

Claims

1. A flying pipe column prevention device for working with pressure, characterized in that: It includes a split shell (1), a straightening mechanism (2), and a locking mechanism (3); the split shell (1) is cylindrical, and the tube is inserted inside the split shell (1); the straightening mechanism (2) and the locking mechanism (3) are provided in several groups, and the several groups of the straightening mechanism (2) and the locking mechanism (3) are distributed in a ring inside the split shell (1), with the tube located at the center of the straightening mechanism (2) and the locking mechanism (3); the straightening mechanism (2) and the locking mechanism (3) clamp the tube.

2. The make-up pressure preventing pipe string flying out device according to claim 1, characterized in that: The segmented shell (1) includes an upper cover plate (11), an outer shell (12), a support plate (13), and a fastening plate (14); the outer shell (12) is evenly divided into several pieces along the circumferential surface, and the several pieces of the outer shell (12) are connected by a combination bolt (153); The upper cover plate (11) is circular in shape with a hole in the middle. The upper cover plate (11) is divided into the same number of pieces as the outer shell (12) along the circumference. Each upper cover plate (11) overlaps the two adjacent outer shells (12) at both ends of the arc. Each upper cover plate (11) has bolt holes at both ends of the arc. The cover plate screws (151) in the bolt holes at both ends are threaded into the cover plate screw holes (121) on the top of the two adjacent outer shells (12). The support plate (13) and the fastening plate (14) are installed sequentially at the bottom of the outer shell (12).

3. The device for preventing pipe string from flying out during pressurized operations according to claim 2, characterized in that: The locking mechanism (3) includes a body (301), the cross-section of which is arc-shaped. Several sets of the bodies (301) of the locking mechanism (3) are spliced ​​together circumferentially to form a complete circle. The back of the body (301) is fixed to the inner wall of the outer shell (12) by bolts. The body (301) has a conical cavity inside, and the inner wall of the conical cavity has an oblique first dovetail groove (312). The first dovetail groove (312) and the arc-shaped slider (307) are connected. The first dovetail wedge (309) at the rear end is in sliding engagement; the front end of the arc-shaped slider (307) is a slip tooth (308), which is used to bite the wellhead tubing; the bottom of the body (301) is provided with a spring hole (313) at an angle, and a spring tube (310) is movably installed in the spring hole (313), and a locking spring (311) is provided inside the spring tube (310); the top of the spring tube (310) is connected to the bottom of the arc-shaped slider (307); The inner wall of the body (301) is provided with a keyway (306) at the top of the first dovetail groove (312), and a locking block (305) is fixed in the keyway (306); the locking block (305) limits the stroke of the arc-shaped slider (307).

4. The device for preventing pipe string from flying out during pressurized operations according to claim 3, characterized in that: The back of the body (301) connected to the outer shell (12) is provided with a plurality of bosses (303), and a groove (302) is formed between two adjacent bosses (303); a plurality of toothed retaining rings (123) are provided on the inner wall of the outer shell (12), and a toothed groove (124) is formed between two adjacent toothed retaining rings (123) along the axial direction; each toothed retaining ring (123) is correspondingly embedded in each groove (302), and each boss (303) is correspondingly embedded in each toothed groove (124); each boss (303) is provided with a locking screw hole (304), and a locking through hole (125) is provided in each toothed groove (124) at a position corresponding to the locking screw hole (304), and a locking screw (152) passes through the locking through hole (125) and is threaded into the locking screw hole (304) to fix the body (301).

5. The device for preventing pipe string from flying out during pressurized operations according to claim 2, characterized in that: The straightening mechanism (2) includes a square housing (206). One end of the square housing (206) is fitted with a second dovetail wedge (201) by a connecting screw (204). The second dovetail wedge (201) is slidably disposed in a second dovetail groove (122) opened axially on the inner wall of the outer housing (12). The other end of the square housing (206) is open, and an outer cavity (208) is movably disposed in the opening. The cross-section of the outer cavity (208) is tapered. An inner cavity (210) is fixedly installed in the outer cavity (208). A first spring groove (202) is provided on the inner side of the second dovetail wedge (201). A second spring groove (211) is provided on the inner side of the inner cavity (210). A straightening spring (205) is installed between the first spring groove (202) and the second spring groove (211). The end of the inner cavity (210) near the axis abuts against the column to straighten the column.

6. The device for preventing pipe string from flying out during pressurized operations according to claim 5, characterized in that: The outer cavity (208) has an outer groove for steel balls at its end, and the inner cavity (210) has an inner groove for steel balls at its end; a spherical cavity is formed between the outer groove for steel balls and the inner groove for steel balls, and a steel ball (209) is movably disposed in the spherical cavity; the outer wall of the steel ball (209) rolls on the column.

7. The device for preventing pipe string from flying out during pressurized operations according to claim 5, characterized in that: The square housing (206) is in the shape of a square cavity. The end of the square housing (206) connected to the second dovetail wedge (201) is provided with four connecting screw holes (207). Each of the four corners of the second dovetail wedge (201) is provided with a connecting through hole (203). The connecting screw (204) passes through the connecting through hole (203) and is threaded onto the connecting screw hole (207), connecting the second dovetail wedge (201) and the square housing (206) into a whole.

8. The device for preventing pipe string from flying out during pressurized operations according to claim 2, characterized in that: The bottom of the outer shell (12) has a section with a reduced diameter. Each outer shell (12) has two supporting ribs (126) on the outer wall at the reduced diameter section. Each supporting rib (126) has a connecting through hole (127). The two supporting ribs (126) on adjacent outer shells (12) are connected by connecting bolts (153) that pass through the connecting through hole (127).

9. The device for preventing pipe string from flying out during pressurized operations according to claim 2, characterized in that: The bottom of the outer shell (12) is supported on the plate (4) of the fixed slip assembly of the live working machine; the flange base (128) at the bottom of the outer shell (12) is provided with annularly distributed base through holes (129). The upper plate (4) of the fixed clamp assembly is a triangular plate; the support plate (13) is divided into three pieces, and the three support plates (13) respectively abut against the three sides of the upper plate (4) of the fixed clamp assembly, and each support plate (13) has three bolt holes. The fastening plate (14) abuts against the bottom of the plate (4) on the fixed clamp assembly; the fastening plate (14) is a circular shape with a hole in the middle, and the fastening plate (14) is divided into three parts along the circumference, and each fastening plate (14) has three bolt holes. The fastening bolts (154) pass through the base through hole (129) on the flange base (128), the bolt hole at the bottom of the support plate (13), and the bolt hole at the bottom of the fastening plate (14) in sequence to fasten the outer shell (12), the support plate (13), and the fastening plate (14).

10. The device for preventing pipe string from flying out during pressurized operations according to any one of claims 2 to 9, characterized in that: The outer shell (12) is divided into three parts along the circumference. The straightening mechanism (2) and the locking mechanism (3) are each provided with six sets. Two sets of the straightening mechanism (2) and two sets of the locking mechanism (3) are fixed inside each outer shell (12).

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