Wellhead sealing device and method

Abstract

The invention relates to the technical field of oil well sealing equipment, in particular to a wellhead sealing device and method.The wellhead sealing device comprises a mounting part and a sealing part; the mounting part is arranged on a wellhead, a first through hole and a second through hole are formed in the axial direction of the wellhead, and one end of the second through hole faces the first through hole and communicates with the first through hole; the sealing part is movably arranged in the second through hole; after the sealing part is inserted into the first through hole, the end face of the end, inserted into the first through hole, of the sealing part abuts against the oil pipe and surrounds the periphery of the oil pipe, and the end, inserted into the first through hole, of the sealing part is arranged in a gap between the oil pipe and the first through hole in a filling mode. When the crossover flange is removed and hoisting operation is carried out, sealing and unsealing are guaranteed to be carried out smoothly, the operation process is simplified, the operation difficulty is reduced, operation and construction under the condition of hoisting heavy objects are avoided, and the operation safety is improved. And when subsequent leakage occurs, secondary extrusion can be performed, so that sealing is performed again, and the sealing stability is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil well sealing equipment, and particularly relates to a wellhead sealing device and method. Background Art

[0002] In the oilfield, downhole electric heating technology is carried out. By lowering an electric heater, the steam flowing through the surface of the electric heater is heated and then injected into the production formation, thereby improving the steam dryness. Among them, the sealing device arranged at the wellhead is one of the important components of the entire electric heating technology.

[0003] The existing sealing devices at the wellhead are generally of the structure form of being tightened by a compression cap. After the tubing is lowered, the wellhead auxiliary sealing can be achieved by tightening the compression cap. However, for the sealing device with the structure form of being tightened by a compression cap, after the tubing is lowered, the conversion flange needs to be disassembled and lifted to a certain height to tighten the compression cap, resulting in risks in the safety during the operation process. Moreover, the sealing effect of the sealing device tightened by the compression cap is extremely susceptible to the tightening degree, equipment material and assembly method, resulting in poor sealing stability. And the existing sealing devices are generally for one-time operation construction. When problems such as leakage occur due to wear of the sealing element, construction needs to be carried out again to replace the sealing element, making the sealing life unstable.

[0004] Therefore, the application effect of the existing sealing devices at the wellhead is poor. Summary of the Invention

[0005] In view of the above problems, the present invention provides a wellhead sealing device and method. Among them, a wellhead sealing device includes:

[0006] An installation part, which is installed on the wellhead, and a first through hole for the tubing to pass through is axially opened on the installation part along the wellhead;

[0007] A second through hole is further opened on the installation part, and one end of the second through hole faces the first through hole and is communicated with the first through hole;

[0008] A sealing part, which is movably arranged in the second through hole, and the sealing part can move towards the direction close to the first through hole;

[0009] After one end of the sealing part close to the first through hole is inserted into the first through hole, the end face of the one end of the sealing part inserted into the first through hole abuts against the tubing and is arranged around the outer periphery of the tubing, and the one end of the sealing part inserted into the first through hole is filled between the gap between the tubing and the first through hole.

[0010] In some specific embodiments, there are two second through holes, and the two second through holes are symmetrically opened on both sides of the first through hole;

[0011] There are two sealing parts, and the two sealing parts are arranged in one-to-one correspondence with the two second through holes.

[0012] In some specific embodiments, the second through hole is radially opened on the mounting part along the first through hole.

[0013] In some specific embodiments, the mounting part includes:

[0014] A fixed disk, the fixed disk is fixedly covered on the wellhead and is coaxially arranged with the wellhead;

[0015] The first through hole is axially opened in the middle of the fixed disk along the axis of the fixed disk;

[0016] The second through hole is adjacent to the first through hole and is opened radially on the fixed disk.

[0017] In some specific embodiments, a bolt assembly is detachably arranged at the bottom of the fixed disk, and the fixed disk is connected to the wellhead through the bolt assembly.

[0018] In some specific embodiments, the sealing part includes:

[0019] A driving component, the driving component is movably arranged in the second through hole, and one end of the driving component close to the first through hole can move in the direction close to the first through hole;

[0020] A sealing component, the sealing component is movably arranged at one end of the driving component close to the first through hole, so that the driving component drives the sealing component to move;

[0021] One end of the sealing component close to the first through hole is adapted to the first through hole.

[0022] In some specific embodiments, the driving component includes:

[0023] A moving rod, one end of the moving rod is movably inserted into the second through hole and is connected to the sealing part, and the other end of the moving rod extends to the outside of the mounting part in the direction away from the first through hole.

[0024] In some specific embodiments, the driving component further includes:

[0025] A connecting sleeve, the connecting sleeve is arranged circumferentially around the second through hole in the second through hole;

[0026] The moving rod passes through the second through hole, and the moving rod is threadedly connected with the second through hole.

[0027] In some specific embodiments, a sealing ring is circumferentially embedded on the inner wall of the connecting sleeve around the circumference of the connecting sleeve, and the inner wall of the sealing ring is in movable abutment with the outer wall of the moving rod.

[0028] In some specific embodiments, between the outer wall of one end of the connecting sleeve close to the first through hole and the inner wall of the second through hole is a stepped structure adapted to each other.

[0029] In some specific embodiments, at one end of the moving rod close to the first through hole, a connecting rod is arranged along the axial direction of the moving rod, and one end of the connecting rod close to the first through hole is rotatably connected to the sealing part.

[0030] In some specific embodiments, one end of the connecting rod close to the moving rod is detachably connected to the moving rod through a pin.

[0031] In some specific embodiments, a bearing is movably arranged around the circumference of the second through hole between the outer wall of the connecting rod and the inner wall of the second through hole.

[0032] In some specific embodiments, the sealing assembly includes:

[0033] A sealing block, which is arranged at one end of the moving rod close to the first through hole, the sealing block is adapted to the first through hole, and one side of the sealing block close to the first through hole can be in abutment with the outer wall of the oil pipe.

[0034] In some specific embodiments, a pressure rod is arranged between the sealing block and the moving rod;

[0035] On the outer wall of the sealing block, a plurality of support members are symmetrically arranged;

[0036] The pressure rod is detachably connected to the plurality of support members.

[0037] In some specific embodiments, on one side of the pressure rod close to the moving rod, a rotating groove is formed, and the pressure rod is rotationally clamped to the moving rod through the rotating groove.

[0038] In some specific embodiments, one end of the support member close to the first through hole bends towards the outside of the support member, so that the end face of one end of the support member close to the first through hole forms an abutting surface;

[0039] In the middle of the abutting surface, a semi-circular groove adapted to the outer circumference of the oil pipe is formed.

[0040] In some specific embodiments, a connecting member is further arranged between the pressure rod and the support member;

[0041] The pressure bar and the support member cooperate with each other to be able to squeeze and limit the connecting member;

[0042] The connecting member is made of an elastic material, and the reaction force during extrusion is used to fill the wear and leakage.

[0043] In some specific embodiments, the connecting member is arranged circumferentially around the second through hole;

[0044] Both ends of the connecting member are respectively arranged around the outer circumferences of the pressure bar and the support member, and are respectively clamped with the pressure bar and the support member.

[0045] In some specific embodiments, one end of the pressure bar close to the first through hole is inserted between the inner walls of the symmetric support members away from the first through hole;

[0046] The pressure bar is connected to each of the symmetric support members through a pin.

[0047] A wellhead sealing method based on the same concept, using the wellhead sealing device described in any of the above specific embodiments, includes the following steps:

[0048] The installation part is installed on the wellhead, and one end of the oil pipe passes through the first through hole of the installation part into the wellhead;

[0049] Drive the sealing part to move towards the direction close to the first through hole until one end of the sealing part close to the first through hole is inserted into the first through hole. At the same time, the gap between the oil pipe and the first through hole is filled by the end of the sealing part inserted into the first through hole;

[0050] Continue to drive the sealing part to move towards the direction close to the first through hole until the end face of the end of the sealing part inserted into the first through hole abuts against the oil pipe and is arranged around the outer circumference of the oil pipe to fill the leakage space of the wellhead sealing device caused by wear.

[0051] The wellhead sealing device of the present invention allows the oil pipe to pass through the first through-hole of the installation part. Only by moving the sealing part arranged in the second through-hole communicating with the first through-hole towards the direction close to the first through-hole until it is inserted into the first through-hole and abuts against the oil pipe, the sealing operation of the external space of the oil pipe can be achieved. Correspondingly, only by moving the sealing part away from the first through-hole can the unsealing operation of the external space of the oil pipe be realized. It replaces the original structure of pressing the gland nut, can ensure the smooth progress of sealing and unsealing while removing the disassembly of the conversion flange and the hoisting operation, simplifies the operation process, reduces the operation difficulty, and avoids the operation construction under the condition of hoisting heavy objects, improving the operation safety. Moreover, by moving the sealing part, sufficient extrusion force can be applied to the oil pipe, thus ensuring the sealing effect and improving the sealing stability. When leakage occurs during subsequent use, secondary extrusion can be carried out to achieve re-sealing, ensuring the stability of the sealing life.

[0052] The wellhead sealing method of the present invention adopts the above-mentioned wellhead sealing device, so it has the same beneficial effects as the above-mentioned wellhead sealing device. Therefore, it will not be elaborated here again.

[0053] Other features and advantages of the present invention will be described in the subsequent specification, and part of them will become obvious from the specification or be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures pointed out in the specification and the drawings. Brief Description of the Drawings

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0055] Figure 1 It shows a schematic diagram of the wellhead sealing device in the embodiment of the present invention;

[0056] Figure 2 It shows a schematic diagram of the wellhead sealing device installed on the wellhead in the embodiment of the present invention;

[0057] Figure 3 It shows a flowchart of the wellhead sealing method in the embodiment of the present invention.

[0058] In the figure, 100 is the installation part; 110 is the fixing plate; 120 is the bolt assembly; 200 is the sealing part; 210 is the driving assembly; 211 is the moving rod; 212 is the connecting sleeve; 2121 is the first connecting ring; 2122 is the second connecting ring; 2123 is the third connecting ring; 213 is the sealing ring; 214 is the connecting rod; 215 is the bearing; 220 is the sealing assembly; 221 is the sealing block; 222 is the pressing rod; 223 is the support; 224 is the connecting piece. Detailed implementation manner

[0059] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0060] Referring to Figure 1 , the present invention provides a wellhead sealing device, including: an installation part 100 and a sealing part 200. The installation part 100 is installed on the wellhead, and a first through hole is axially opened on the installation part 100 along the wellhead. A second through hole is also opened on the installation part 100, and one end of the second through hole communicates with the first through hole. The sealing part 200 is movably arranged in the second through hole, and the sealing part 200 can move in the direction close to the first through hole until the end of the sealing part 200 close to the first through hole is inserted into the first through hole and abuts against the oil pipe.

[0061] Specifically, the installation part 100 is installed above the wellhead. The wellhead can be blocked through the installation part 100. Among them, the first through hole is axially opened on the installation part 100 along the wellhead for the oil pipe to pass through, so that the oil pipe can pass through the first through hole and reach the well. The second through hole is opened on one side of the installation part 100, so that the second through hole is located on one side of the first through hole, and one end of the second through hole is communicated with the first through hole. The sealing part 200 is arranged in the second through hole, and the sealing part 200 is movably connected with the second through hole. The sealing part 200 can move in the second through hole along the axial direction of the second through hole towards the direction close to the first through hole or away from the first through hole. When the sealing part 200 moves in the second through hole along the axial direction of the second through hole towards the direction close to the first through hole until one end of the sealing part 200 close to the first through hole is inserted into the first through hole, one end of the sealing part 200 inserted into the first through hole can abut against the outer wall of the oil pipe passing through the first through hole. Moreover, the shape and size of one end of the sealing part 200 that can be inserted into the first through hole are also adapted to the shape and size of the first through hole. When one end of the sealing part 200 inserted into the first through hole abuts against the outer wall of the oil pipe passing through the first through hole, other spaces in the first through hole can be blocked through one end of the sealing part 200 inserted into the first through hole, so as to seal the outer space of the oil pipe and realize the sealing operation. When sealing is not required, only by moving the sealing part 200 away from the first through hole can the unsealing operation of the outer space of the oil pipe be realized. It replaces the original structure form of pressing the cap, can still ensure the smooth progress of sealing and unsealing while removing the disassembly of the conversion flange and the hoisting operation, simplifies the operation process, reduces the operation difficulty, and avoids the operation construction under the condition of hoisting heavy objects, thus improving the operation safety. Moreover, when one end of the sealing part 200 inserted into the first through hole abuts against the outer wall of the oil pipe passing through the first through hole, sufficient extrusion force can be applied to the outer wall of the oil pipe by continuously moving the sealing part 200 closer to the first through hole, so as to ensure the sealing effect and improve the sealing stability.

[0062] In some specific embodiments of the present invention, referring to Figure 1 , there are two second through holes, and the two second through holes are symmetrically opened on both sides of the first through hole. There are two sealing parts 200, and the two sealing parts 200 are arranged in one-to-one correspondence with the two second through holes.

[0063] Specifically, two second through-holes are symmetrically formed on both sides of the mounting portion 100, such that the two second through-holes can be symmetrically located on both sides of the first through-hole, and one end of each of the two second through-holes communicates with the first through-hole. Two sealing portions 200 are respectively disposed in the two second through-holes, and each sealing portion 200 can move in the corresponding second through-hole along the axial direction of the second through-hole towards or away from the first through-hole. When the two sealing portions 200 move in the corresponding second through-holes along the axial direction of the second through-holes towards the first through-hole until one end of each of the two sealing portions 200 close to the first through-hole is inserted into the first through-hole, the inserted ends of the two sealing portions 200 in the first through-hole can respectively abut against both sides of the outer wall of the oil pipe passing through the first through-hole. Moreover, the shape and size of the inserted ends of the two sealing portions 200 that can be inserted into the first through-hole respectively match the shape and size of both sides of the first through-hole. When the inserted ends of the two sealing portions 200 in the first through-hole respectively abut against both sides of the outer wall of the oil pipe passing through the first through-hole, the ends of the two sealing portions 200 close to the first through-hole also abut against each other, so that the ends of the two sealing portions 200 close to the first through-hole can cooperate with each other to surround the outside of the oil pipe, and the other spaces in the first through-hole can be blocked by the inserted ends of the two sealing portions 200 in the first through-hole, thereby sealing the outside space of the oil pipe. The cooperation of the two sealing portions 200 facilitates the sealing of the outside space of the oil pipe, can reduce the probability of leakage in the sealing, and the shape and size of the inserted ends of the sealing portions 200 in the first through-hole are also convenient for design, which can reduce the processing cost.

[0064] It should be noted that there can be more than two second through-holes, and there can also be more than two sealing portions 200. The more than two sealing portions 200 and the more than two second through-holes are arranged in one-to-one correspondence, and the outside space of the oil pipe can be sealed jointly by the more than two sealing portions 200. However, when the number of the sealing portions 200 is too large, the number of the junctions will inevitably increase, thus increasing the probability of gaps. When there are two sealing portions 200, it is not only convenient for sealing the outside space of the oil pipe, but also can effectively control the probability of gaps.

[0065] In some specific embodiments of the present invention, referring to Figure 1 , the second through-hole is formed on the mounting portion 100 along the radial direction of the first through-hole. Specifically, the second through-hole is horizontally formed, such that the second through-hole is arranged along the radial direction of the first through-hole, and when abutting against the outer wall of the oil pipe, a squeezing force can be applied to the outer wall of the oil pipe along the radial direction of the oil pipe, which can further improve the implementation effect of the squeezing force, so that a sufficient squeezing force can be applied to the oil pipe through the movement of the sealing portion 200, thereby ensuring the sealing effect and improving the sealing stability.

[0066] In some specific embodiments of the present invention, referring to Figure 1, the installation part 100 includes: a fixed disk 110. The fixed disk 110 is fixedly covered on the wellhead and is coaxially arranged with the wellhead. The first through hole is axially formed in the middle of the fixed disk 110 along the axis of the fixed disk 110. The second through hole is radially formed on one side of the first through hole along the axis of the fixed disk 110. Specifically, the fixed disk 110 is covered above the wellhead, and the bottom surface of the fixed disk 110 is connected to the end of the wellhead, so that the axis of the fixed disk 110 is collinear with the axis of the wellhead. Among them, the first through hole is axially formed along the axis of the fixed disk 110, so that the first through hole can also be axially arranged along the wellhead. The second through hole is radially formed along the axis of the fixed disk 110, so that the second through hole can also be radially arranged along the first through hole. The sealing part 200 can apply sufficient extrusion pressure to the oil pipe passing through the first through hole, so as to ensure the sealing effect and improve the sealing stability.

[0067] Further, the fixed disk 110 can be a four-way component. The first through hole can be formed by two directly opposite and communicating channels of the four-way component, and the other two second through holes can be formed by the other two channels of the four-way component. The structure is simple, the cost is low, and it is convenient to use.

[0068] In some specific embodiments of the present invention, refer to Figure 2 , a bolt assembly 120 is detachably arranged at the bottom of the fixed disk 110, and the fixed disk 110 is connected to the wellhead through the bolt assembly 120. Specifically, the bolt assembly 120 includes a plurality of bolts, and the plurality of bolts are evenly threadedly connected to the bottom side of the fixed disk 110, which is convenient to connect to the wellhead through the plurality of bolts.

[0069] Further, a bolt assembly 120 is also detachably arranged at the top of the fixed disk 110, so that it can be connected to the blowout preventer through a plurality of bolts, which is convenient for installation.

[0070] In some specific embodiments of the present invention, refer to Figure 1 , the sealing part 200 includes: a driving component 210 and a sealing component 220. The driving component 210 is movably arranged in the second through hole, and one end of the driving component 210 close to the first through hole can move in the direction close to the first through hole. The sealing component 220 is movably arranged at one end of the driving component 210 close to the first through hole, so that the driving component 210 drives the sealing component 220 to move. One end of the sealing component 220 close to the first through hole is adapted to the first through hole.

[0071] Specifically, the driving component 210 is disposed along the axial direction of the second through hole and is movably connected to the second through hole. By applying a force to the driving component 210, the driving component 210 can be driven to move along the axial direction of the second through hole, that is, the driving component 210 can be driven to move towards or away from the first through hole. The sealing component 220 is disposed at one end of the driving component 210 close to the first through hole and is movably connected to the second through hole. When the driving component 210 is driven to move towards or away from the first through hole, the sealing component 220 can be driven to move towards or away from the first through hole together. Wherein, a contact side is formed on the side of the sealing component 220 close to the first through hole. When the driving component 210 is driven to drive the sealing component 220 to move towards the first through hole until the sealing component 220 is inserted into the first through hole, the contact side of the sealing component 220 can be in contact with the outer wall of the oil pipe in the first through hole. Moreover, the shape and size of the contact side of the sealing component 220 are adapted to the shape and size of the first through hole. As the driving component 210 continues to drive the sealing component 220 to move towards the first through hole together, the side of the contact side of the sealing component 220 can be in contact with the side of the contact side of the sealing component 220 of another sealing part 200. Thus, through the cooperation of multiple sealing components 220, the outer wall of the oil pipe can be surrounded circumferentially around the oil pipe, and the gap between the outer wall of the oil pipe and the inner wall of the first through hole, that is, the external space of the oil pipe, can be blocked, thereby realizing the sealing operation. The sealing and unsealing operations of the external space of the oil pipe can be realized only by moving the sealing part 200 towards or away from the first through hole. Instead of the original structure form of pressing the gland, it can ensure the smooth progress of sealing and unsealing while removing the disassembly of the conversion flange and the hoisting operation, simplifies the operation process, reduces the operation difficulty, and avoids the operation construction under the condition of hoisting heavy objects, improving the operation safety. It can also apply sufficient extrusion force to the oil pipe, thereby ensuring the sealing effect and improving the sealing stability.

[0072] In some specific embodiments of the present invention, referring to Figure 1, the driving component 210 includes: a moving rod 211. One end of the moving rod 211 is movably inserted into the second through hole and connected to the sealing portion 200, and the other end of the moving rod 211 extends away from the first through hole to the outside of the mounting portion 100. Specifically, one end of the moving rod 211 is movably inserted into the second through hole from the end of the second through hole away from the first through hole, and the end of the moving rod 211 inserted into the second through hole is connected to the sealing assembly 220. By moving the moving rod 211 in the second through hole, the sealing assembly 220 can be driven to move together. The other end of the moving rod 211, that is, the end of the moving rod 211 away from the second through hole, extends away from the first through hole along the axial direction of the second through hole to the outside of the fixed disk 110, so as to facilitate driving the moving rod 211 to move in the second through hole from the outside of the fixed disk 110. It replaces the original structure of pressing the gland, can still ensure the smooth sealing and unsealing while removing the disassembly of the conversion flange and the hoisting operation, simplifies the operation process, and reduces the operation difficulty.

[0073] In some specific embodiments of the present invention, referring to Figure 1 , the driving component 210 further includes: a connecting sleeve 212. The connecting sleeve 212 is disposed around the circumference of the second through hole in the second through hole. The moving rod 211 is disposed through the second through hole, and the moving rod 211 is threadedly connected to the second through hole. Specifically, the connecting sleeve 212 is a cylindrical structure, and one end of the connecting sleeve 212 is inserted into the second through hole along the axial direction of the second through hole from the end of the second through hole away from the first through hole. The moving rod 211 is disposed through the connecting sleeve 212, so that one end of the moving rod 211 passes through the connecting sleeve 212 and is connected to the sealing assembly 220, and the other end of the moving rod 211 is disposed outside the connecting sleeve 212 along the axial direction of the second through hole. The outer wall of the moving rod 211 is threadedly connected to the inner wall of the connecting sleeve 212, so that the moving rod 211 can be driven to move along the axial direction of the second through hole by rotating the moving rod 211, and the moving rod 211 can be limited, avoiding the movement of the moving rod 211 under pressure and ensuring the stability of the seal. At the same time, since the end of the moving rod 211 away from the first through hole is disposed outside the connecting sleeve 212 along the axial direction of the second through hole, it is convenient to drive the moving rod 211 to rotate. And the threaded connection relationship between the outer wall of the moving rod 211 and the inner wall of the connecting sleeve 212 can form a sealing structure between the outer wall of the moving rod 211 and the inner wall of the connecting sleeve 212, ensuring the sealing effect.

[0074] Further, the connecting sleeve 212 and the second through hole are in a threaded connection relationship, which can facilitate the installation and disassembly while ensuring the sealing between the connecting sleeve 212 and the second through hole.

[0075] In some specific embodiments of the present invention, referring to Figure 1, a sealing ring 213 is circumferentially embedded on the inner wall of the connecting sleeve 212 around the circumference of the connecting sleeve 212, and the inner wall of the sealing ring 213 is movably abutted against the outer wall of the moving rod 211. Specifically, a sealing groove is circumferentially formed on the inner wall of the connecting sleeve 212 around the circumference of the connecting sleeve 212, and the sealing ring 213 is embedded in the sealing groove, so that the connecting sleeve 212 can be abutted against the outer wall of the moving rod 211 through the sealing ring 213, and the gap between the moving rod 211 and the connecting sleeve 212 can be blocked through the sealing ring 213, thereby ensuring the sealing performance.

[0076] In some specific embodiments of the present invention, referring to Figure 1 , the outer wall of one end of the connecting sleeve 212 close to the first through hole and the inner wall of the second through hole are of a mutually adapted stepped structure.

[0077] Specifically, the connecting sleeve 212 includes: a first connecting ring 2121, a second connecting ring 2122 and a third connecting ring 2123. One end of the first connecting ring 2121 is inserted into one end of the third connecting ring 2123, and one end of the second connecting ring 2122 is inserted into the other end of the third connecting ring 2123. Moreover, there is a gap between the end of the first connecting ring 2121 inserted into the third connecting ring 2123 and the end of the second connecting ring 2122 inserted into the third connecting ring 2123. Thus, a sealing groove is formed by the end face of the end of the first connecting ring 2121 inserted into the third connecting ring 2123, the end face of the end of the second connecting ring 2122 inserted into the third connecting ring 2123 and the inner wall of the third connecting ring 2123, ensuring the sealing performance of the connecting sleeve 212 itself after the sealing ring 213 is provided. And, an embedding groove is circumferentially formed at one end of the second through hole far from the first through hole around the circumference of the second through hole, and the groove wall of the embedding groove is adapted to the outer wall of the connecting sleeve 212 composed of the first connecting ring 2121, the second connecting ring 2122 and the third connecting ring 2123. When one end of the first connecting ring 2121 and the third connecting ring 2123 close to the first connecting ring 2121 are inserted into the embedding groove, the groove wall of the embedding groove can just be abutted against the outer wall of the first connecting ring 2121 and the outer wall of one end of the third connecting ring 2123 close to the first connecting ring 2121, so that a stepped structure can be formed between the groove wall of the embedding groove and the outer wall of the connecting sleeve 212, thereby further improving the sealing performance between the connecting sleeve 212 and the second through hole. Among them, the outer wall of one end of the third connecting ring 2123 close to the first connecting ring 2121 is in threaded connection with the groove wall of the embedding groove, which is convenient for disassembly and can ensure the sealing performance.

[0078] In some specific embodiments of the present invention, referring to Figure 1, a connecting rod 214 is arranged at one end of the moving rod 211 close to the first through hole along the axial direction of the moving rod 211, and one end of the connecting rod 214 close to the first through hole is rotatably connected to the sealing portion 200. Specifically, a connecting rod 214 is arranged at one end of the moving rod 211 close to the first through hole. One end of the connecting rod 214 is connected to the middle of the end face of the end of the moving rod 211 close to the first through hole, and the other end of the connecting rod 214 extends along the axial direction of the second through hole towards the direction close to the first through hole. One end of the connecting rod 214 close to the first through hole is rotatably connected to the sealing assembly 220. When the sealing assembly 220 is driven to move together by moving the moving rod 211, the connecting rod 214 can rotate together with the moving rod 211 relative to the sealing assembly 220, thereby avoiding driving the sealing assembly 220 to rotate together and ensuring the accuracy of sealing.

[0079] In some specific embodiments of the present invention, referring to Figure 1 , one end of the connecting rod 214 close to the moving rod 211 is detachably connected to the moving rod 211 through a pin. Specifically, the end of the connecting rod 214 away from the first through hole is inserted into the moving rod 211 along the axial direction of the moving rod 211, and a pin is inserted into the moving rod 211 along the radial direction of the moving rod 211. The pin is arranged through the end of the connecting rod 214 away from the first through hole, so as to ensure the connection stability after installation, enable the connecting rod 214 to rotate together with the moving rod 211, and facilitate installation and disassembly.

[0080] In some specific embodiments of the present invention, referring to Figure 1 , a bearing 215 is movably arranged circumferentially around the second through hole between the outer wall of the connecting rod 214 and the inner wall of the second through hole. Specifically, the bearing 215 is clamped between the moving rod 211 and the sealing assembly 220, and the bearing 215 is arranged around the outer wall of the connecting rod 214 circumferentially around the second through hole, so as to ensure the smooth rotation of the moving rod 211 and the connecting rod 214 through the setting of the bearing 215.

[0081] In some specific embodiments of the present invention, referring to Figure 1, the sealing assembly 220 includes: a sealing block 221. The sealing block 221 is disposed at one end of the moving rod 211 close to the first through hole. The sealing block 221 is adapted to the first through hole, and one side of the sealing block 221 close to the first through hole can abut against the outer wall of the oil pipe. Specifically, the sealing block 221 is disposed at one end of the connecting rod 214 close to the first through hole and is rotatably connected to the connecting rod 214, so that one side of the sealing block 221 close to the first through hole forms the abutting side of the sealing assembly 220. When the moving rod 211 drives the connecting rod 214 to rotate, it can drive the connecting rod 214 to move in the direction close to the first through hole together, thereby pushing the sealing block 221 to move in the direction close to the first through hole until the sealing block 221 is inserted into the first through hole and abuts against the outer wall of the oil pipe. The shape and size of the sealing block 221 are adapted to the shape and size of the first through hole. As the moving rod 211 and the connecting rod 214 continue to drive the sealing block 221 to move in the direction close to the first through hole, the side of the sealing block 221 can abut against the side of the sealing block 221 of the sealing assembly 220 of another sealing portion 200. Thus, through the mutual cooperation of multiple sealing blocks 221, the outer wall of the oil pipe can be surrounded circumferentially around the oil pipe, and the gap between the outer space of the oil pipe, that is, the outer wall of the oil pipe and the inner wall of the first through hole, can be blocked, thereby realizing the sealing operation.

[0082] In some specific embodiments of the present invention, referring to Figure 1 , a pressure rod 222 is disposed between the sealing block 221 and the moving rod 211, and support members 223 are symmetrically disposed on the outer wall of the sealing block 221; the pressure rod 222 is detachably connected to the support members 223. Specifically, the pressure rod 222 is slidably disposed between one end of the connecting rod 214 close to the first through hole and the side of the sealing block 221 away from the first through hole, thereby ensuring the connection stability and avoiding the problem that the sealing block 221 and the connecting rod 214 are not easily connected. A plurality of support members 223 are disposed around the circumference of the second through hole and symmetrically surround the outer wall of the sealing block 221, and are slidably connected to the inner wall of the second through hole. The support members 223 can support the sealing block 221, so that when the sealing block 221 is squeezed, the deformation shape of the sealing block 221 is restricted, and further the sealing block 221 can just block the outer space of the oil pipe, avoiding the generation of gaps between the sealing block 221 and another sealing block 221. Moreover, the movement of the pressure rod 222 close to the first through hole is detachably connected to one end of the support member 223 away from the first through hole, so that the pressure rod 222 is indirectly connected to the sealing block 221.

[0083] Furthermore, one end of the push rod 222 close to the first through hole is inserted between the inner walls of a plurality of symmetrically arranged support members 223 away from the first through hole. The push rod 222 is connected to each of the symmetrically arranged support members 223 through a pin. When the push rod 222 moves, it can push or pull each of the symmetrically arranged support members 223 to move together through the connected pins, and at the same time drive the sealing block 221 to move.

[0084] In some specific embodiments of the present invention, referring to Figure 1 , a rotation groove is formed on one side of the push rod 222 close to the moving rod 211, and the push rod 222 is rotationally clamped with the moving rod 211 through the rotation groove. Specifically, the rotation groove is formed in the middle of the end face of the end of the push rod 222 away from the first through hole, so that the rotation groove is arranged opposite to the connecting rod 214. One end of the connecting rod 214 close to the first through hole is rotationally inserted into the rotation groove and rotationally clamped through a clamping structure, so that when the moving rod 211 drives the connecting rod 214 to rotate and move, it will not drive the sealing block 221 to rotate together, ensuring the accuracy of sealing.

[0085] In some specific embodiments of the present invention, referring to Figure 1 , one end of the support member 223 close to the first through hole is bent outward of the support member 223, so that the end face of the end of the support member 223 close to the first through hole forms an abutting surface. Specifically, one end of the support member 223 close to the first through hole is bent in the direction away from the sealing block 221 along the radial direction of the second through hole until the outer wall of the end of the support member 223 close to the first through hole is in sliding abutment with the inner wall of the second through hole, so that the end face of the end of the support member 223 close to the first through hole forms an abutting surface. When the moving rod 211 and the connecting rod 214 drive the push rod 222, the support member 223 and the sealing block 221 to move together in the direction close to the first through hole until the sealing block 221 cooperates with another sealing block 221 to surround the outer wall of the oil pipe, by continuously driving the support member 223 and the sealing block 221 to move in the direction close to the first through hole, the abutting surfaces of the two support members 223 can be made to abut against each other, thus ensuring the accuracy of sealing and improving the sealing effect.

[0086] Furthermore, a semi-circular groove is formed in the middle of the abutting surface of the support member 223 and in the middle of the side of the sealing block 221 close to the oil pipe. The semi-circular groove is adapted to the outer circumference of the oil pipe, so as to facilitate abutting against the outer wall of the oil pipe and filling the gap between the outer wall of the oil pipe and the inner wall of the first through hole.

[0087] In some specific embodiments of the present invention, referring to Figure 1, the compression bar 222 and the support member 223 are connected by a connecting member 224. The compression bar 222 and the support member 223 cooperate with each other to be able to squeeze and limit the connecting member 224. Specifically, the connecting member 224 is arranged between the compression bar 222 and the support member 223, and both ends of the connecting member 224 are respectively connected to the compression bar 222 and the support member 223. There are intervals between the sides of multiple symmetric support members 223, and the connecting member 224 can contact the sealing block 221 through the intervals between the sides of multiple symmetric support members 223 for bearing and pushing the sealing block 221. The connecting member 224 is made of compressible material, and the connecting member 224 can be squeezed through the cooperation between the compression bar 222 and the support member 223. Among them, the compression bar 222 squeezes the connecting member 224, and the support member 223 limits the connecting member 224. When the sealing block 221 and another sealing block 221 cooperate with each other to surround the outer wall of the oil pipe, and the abutting surfaces of the two support members 223 also abut against each other, continue to drive the compression bar 222 to move in the direction close to the first through hole by the movement of the moving rod 211 and the connecting rod 214, the connecting member 224 can be compressed, causing the connecting member 224 to undergo compressive deformation, so as to further strengthen the extrusion force on the sealing block 221 and the support through the reaction force generated after the compression of the connecting member 224, forming a two-stage sealing structure and improving the sealing effect.

[0088] Furthermore, the connecting member 224 is made of elastic material. When the rigid sealing formed by the support member 223 becomes less effective due to wear, the leakage space generated by wear can be filled through the reaction force generated during extrusion, thereby restoring the sealing effect, avoiding replacing the sealing member during complex operation construction, reducing the cost, and extending the service life.

[0089] In some specific embodiments of the present invention, refer to Figure 1 , the connecting member 224 is arranged circumferentially around the second through hole. Both ends of the connecting member 224 are respectively arranged around the outer circumferences of the compression bar 222 and the support member 223 and are respectively clamped with the compression bar 222 and the support member 223. Specifically, a first compression groove is formed on the outer wall of the compression bar 222, and a second compression groove is formed on the outer wall of the support member 223. Among them, since one end of the support member 223 close to the first through hole is a bent structure, the second compression groove is formed by this bent structure and the unbent outer wall of the support member 223. One end of the connecting member 224 is sleeved in the first compression groove, and the other end of the connecting member 224 is sleeved in the second compression groove, which can not only further provide an extrusion force through the compressed connecting member 224, but also seal between the support member 223 and the second through hole and between the compression bar 222 and the second through hole through the connecting member 224 to ensure the sealing effect.

[0090] Refer to Figure 3, the present invention also provides a wellhead sealing method, which uses the wellhead sealing device described in any of the above specific embodiments, and includes the following steps: The installation part 100 is installed on the wellhead, and one end of the oil pipe passes through the first through hole of the installation part 100 into the wellhead; Drive the sealing part 200 to move towards the direction close to the first through hole until the end of the sealing part 200 close to the first through hole is inserted into the first through hole; Continue to drive the sealing part 200 to move towards the direction close to the first through hole until the end face of the sealing part 200 inserted into the first through hole abuts against the oil pipe and is arranged around the outer periphery of the oil pipe. At the same time, the gap between the oil pipe and the first through hole is filled by the end of the sealing part 200 inserted into the first through hole. The first through hole of the installation part 100 of the wellhead sealing device is used for the oil pipe to pass through. By only driving the sealing part 200 arranged in the second through hole communicated with the first through hole to move towards the direction close to the first through hole, until the plurality of sealing blocks 221 and the support member 223 abut against each other, the sealing operation of the external space of the oil pipe can be realized. Correspondingly, by only driving the sealing part 200 to move away from the first through hole, the unsealing operation of the external space of the oil pipe can be realized. Instead of the original structure form of pressing the gland, it can ensure the smooth progress of sealing and unsealing while removing the disassembly of the conversion flange and the hoisting operation, simplifies the operation process, reduces the operation difficulty, and avoids the operation construction under the condition of hoisting heavy objects, improving the operation safety. Moreover, sufficient extrusion force can be applied to the oil pipe, so as to ensure the sealing effect and improve the sealing stability.

[0091] Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: They can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wellhead sealing device, characterized in that, Comprising: An installation part (100) which is installed on the wellhead, and a first through hole for an oil pipe to pass through is axially opened in the installation part (100) along the wellhead; A second through hole is further opened in the installation part (100), and one end of the second through hole faces the first through hole and is communicated with the first through hole; A sealing part (200) which is movably arranged in the second through hole, and the sealing part (200) can move towards the direction close to the first through hole; After one end of the sealing part (200) close to the first through hole is inserted into the first through hole, the end face of the end of the sealing part (200) inserted into the first through hole abuts against the oil pipe and is arranged around the outer periphery of the oil pipe, and the end of the sealing part (200) inserted into the first through hole is filled between the gap between the oil pipe and the first through hole.

2. The wellhead sealing device according to claim 1, characterized in that, There are two second through holes, and the two second through holes are symmetrically opened on both sides of the first through hole; There are two sealing parts (200), and the two sealing parts (200) are arranged in one-to-one correspondence with the two second through holes.

3. The wellhead sealing device according to claim 1, characterized in that, The second through hole is radially opened in the installation part (100) along the first through hole.

4. The wellhead sealing device according to any one of claims 1 to 3, characterized in that, The installation part (100) includes: A fixed disk (110) which is fixedly covered on the wellhead and is coaxially arranged with the wellhead; The first through hole is axially opened in the middle of the fixed disk (110) along the fixed disk (110); The second through hole is radially adjacent to the first through hole along the fixed disk (110).

5. The wellhead sealing device according to claim 4, wherein, A bolt assembly (120) is detachably arranged at the bottom of the fixed disk (110), and the fixed disk (110) is connected with the wellhead through the bolt assembly (120).

6. The wellhead sealing device according to any one of claims 1 to 3, characterized in that, The sealing part (200) includes: A driving assembly (210) which is movably arranged in the second through hole, and one end of the driving assembly (210) close to the first through hole can move towards the direction close to the first through hole; A sealing assembly (220) which is movably arranged at one end of the driving assembly (210) close to the first through hole, so that the driving assembly (210) drives the sealing assembly (220) to move; One end of the sealing assembly (220) close to the first through hole is adapted to the first through hole.

7. The wellhead sealing device according to claim 6, characterized in that, The driving assembly (210) includes: A moving rod (211), one end of the moving rod (211) is movably inserted into the second through hole and is connected with the sealing part (200), and the other end of the moving rod (211) extends towards the outside of the installation part (100) in the direction away from the first through hole.

8. The wellhead sealing device according to claim 7, wherein, The driving assembly (210) further includes: A connecting sleeve (212) which is arranged in the second through hole around the circumference of the second through hole; The moving rod (211) is arranged through the second through hole, and the moving rod (211) is threadedly connected with the second through hole.

9. The wellhead sealing device according to claim 8, wherein, A sealing ring (213) is circumferentially embedded on the inner wall of the connecting sleeve (212) around the circumference of the connecting sleeve (212), and the inner wall of the sealing ring (213) is in movable abutment with the outer wall of the moving rod (211).

10. The wellhead sealing device according to claim 8, characterized in that, A stepped structure that fits each other is formed between the outer wall of one end of the connecting sleeve (212) close to the first through hole and the inner wall of the second through hole.

11. The wellhead sealing device according to claim 8, characterized in that, One end of the moving rod (211) close to the first through hole is provided with a connecting rod (214) along the axial direction of the moving rod (211), and one end of the connecting rod (214) close to the first through hole is rotatably connected to the sealing portion (200).

12. The wellhead sealing device according to claim 11, characterized in that, One end of the connecting rod (214) close to the moving rod (211) is detachably connected to the moving rod (211) by a pin.

13. The wellhead sealing device according to claim 11, characterized in that, A bearing (215) is circumferentially and movably arranged between the outer wall of the connecting rod (214) and the inner wall of the second through hole around the circumference of the second through hole.

14. The wellhead sealing device according to claim 8, characterized in that, The sealing assembly (220) includes: A sealing block (221) is arranged at one end of the moving rod (211) close to the first through hole. The sealing block (221) is adapted to the first through hole, and one side of the sealing block (221) close to the first through hole can abut against the outer wall of the oil pipe.

15. The wellhead sealing device according to claim 14, characterized in that, A pressure rod (222) is arranged between the sealing block (221) and the moving rod (211); A plurality of support members (223) are symmetrically arranged on the outer wall of the sealing block (221); The pressure rod (222) is detachably connected to the plurality of support members (223).

16. The wellhead sealing device according to claim 15, characterized in that, A rotating groove is formed on one side of the pressure rod (222) close to the moving rod (211), and the pressure rod (222) is rotatably clamped with the moving rod (211) through the rotating groove.

17. The wellhead sealing device according to claim 15, characterized in that, One end of the support member (223) close to the first through hole bends towards the outside of the support member (223), so that the end face of one end of the support member (223) close to the first through hole forms an abutting surface; A semi-circular groove adapted to the outer circumference of the oil pipe is formed in the middle of the abutting surface.

18. The wellhead sealing device according to claim 15, characterized in that, A connecting member (224) is further arranged between the pressure rod (222) and the support member (223); The pressure rod (222) and the support member (223) cooperate with each other to be able to squeeze and limit the connecting member (224); The connecting member (224) is made of an elastic material, and the wear loss is filled by the reaction force during extrusion.

19. The wellhead sealing device according to claim 18, wherein, The connecting member (224) is arranged around the circumference of the second through hole; Two ends of the connecting member (224) are respectively arranged around the outer circumferences of the pressure rod (222) and the support member (223), and are respectively clamped with the pressure rod (222) and the support member (223).

20. The wellhead sealing device according to claim 19, characterized in that, One end of the pressure rod (222) close to the first through hole is inserted between the inner walls of the symmetric support members (223) far from the first through hole; The pressure rod (222) is connected to each of the symmetric support members (223) by a pin.

21. A wellhead sealing method, which uses the wellhead sealing device described in any one of claims 1 to 20, is characterized in that, Including the following steps: The installation part (100) is installed on the wellhead, and one end of the oil pipe passes through the first through hole of the installation part (100) into the wellhead; Drive the sealing part (200) to move towards the direction close to the first through hole until one end of the sealing part (200) close to the first through hole is inserted into the first through hole. At the same time, fill the gap between the oil pipe and the first through hole with one end of the sealing part (200) inserted into the first through hole; Continue to drive the sealing part (200) to move towards the direction close to the first through hole until the end face of one end of the sealing part (200) inserted into the first through hole abuts against the oil pipe and is arranged around the outer periphery of the oil pipe, filling the leakage space of the wellhead sealing device caused by wear.

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