A kind of non-disassembled rotary blowout preventer for wellhead

Abstract

The present invention discloses a wellhead disassembly-free rotary blowout preventer, which relates to the technical field of petroleum machinery equipment. The present invention includes: a housing; a central hole is provided at the top of the housing; a rotary assembly, the rotary assembly includes an outer cylinder and a rotary head, an oil inlet ring groove and an oil return ring groove are spaced apart along the axial direction of the outer side wall of the outer cylinder, an oil return port communicating with a sealing cavity is provided at the upper part of the inner side wall, and an oil inlet port communicating with the sealing cavity is provided at the lower part; an oil distribution assembly, the upper part of the oil distribution assembly is sleeved on the outer side wall of the outer cylinder, and the lower part is fixedly connected to the housing. An oil inlet hole communicating with the oil inlet ring groove and an oil return hole communicating with the oil return ring groove are provided at the upper part of the oil distribution assembly. The oil inlet hole is connected to an oil inlet pipe, and the oil return hole is connected to an oil return pipe. By providing the oil distribution assembly, the present invention enables the automatic connection between the rotary assembly and the hydraulic circuit after the rotary assembly is installed in place, eliminating the need for manual repeated disassembly and assembly of the hydraulic pipeline, avoiding manual high-altitude operations, and improving production efficiency and work safety.

Description

Technical Field

[0001] The present invention relates to the technical field of oil drilling machinery and equipment, and more particularly to a wellhead disassembly-free rotary blowout preventer. Background Art

[0002] Rotary blowout preventers are used to seal drill pipes during drilling and are essential key equipment in managed pressure drilling and underbalanced drilling. Rotary blowout preventers are mainly divided into two categories: active and passive. Due to factors such as complex control and very inconvenient on-site replacement of rubber cores, the application amount of active ones is much less than that of passive ones. The rubber core of the passive rotary blowout preventer has a short service life and often requires on-site replacement of the rubber core. The passive rotary blowout preventer generally includes a housing, a rotary assembly, and a clamp for connecting the housing and the rotary assembly. For example, the invention patent with the publication number CN1254052A discloses a drilling rotary blowout preventer, which is exactly a passive rotary blowout preventer. It includes a rotary assembly and a housing. A central pipe is provided in the rotary assembly. An upper connecting flange is provided at the upper part of the central pipe and is fixed on the central pipe by bolts and positioning pins. An upper rubber core is provided at the upper part of the central pipe. An oil pressure capsule is provided in the annulus between the upper rubber core and the central pipe. A lower rubber core leakage observation hole is provided at the upper part of the central pipe. A sliding bearing centering sleeve is provided outside the central pipe. A lubricating oil channel is provided in the sliding bearing centering sleeve, and a lubricating oil injection hole and a discharge hole are provided outside it. An axial thrust ball bearing and a radial tapered roller bearing are provided outside the middle part of the central pipe. A V-shaped packing, an anti-wear centering sleeve, cooling fins, and a cooling water inlet and outlet are provided at the lower part of the central pipe. A lower rubber core is also provided at the lower part of the central pipe and is fixed on the central pipe by bolts; the clamp is provided outside the housing and fixedly connects the rotary assembly and the housing through bolts. When the lower rubber core needs to be replaced, as long as the fixing bolts on the clamp are loosened, the rotary assembly can be lifted out together with the lower rubber core for replacement of the lower rubber. However, there are the following prominent problems in the process of replacing the rubber core: during the process of replacing the rubber core, the fixing bolts of the clamp need to be loosened, the rotary assembly needs to be lifted out, and before the rotary assembly is lifted out, the control oil circuit needs to be cut off and the lubricating oil pipeline on it needs to be removed to prevent lubricating oil leakage caused by pipeline breakage. However, since the rotary blowout preventer is located at the highest position of the wellhead, the disassembly and assembly operations are very inconvenient, the disassembly and assembly efficiency is low, and the safety is poor, which is likely to cause too long a drilling stop time, thus triggering other drilling accidents.

[0003] Therefore, how to provide a rotary blowout preventer with simple operation and easy disassembly and assembly is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention aims to provide a wellhead non-disassembling and assembling type rotating blowout preventer to at least to some extent solve the problems of cumbersome manual disassembly and assembly, low efficiency and poor safety when replacing the rubber core of the existing rotating blowout preventer.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A wellhead non-disassembling and assembling type rotating blowout preventer, comprising:

[0007] A housing; a central hole is provided at the top of the housing;

[0008] A rotating assembly, the rotating assembly includes an outer cylinder and a rotating head, the outer cylinder is installed in the central hole, an upper dynamic seal ring is installed on the inner wall of the upper end of the outer cylinder, and a lower dynamic seal ring is installed on the inner wall of the lower end. The upper part of the rotating head is rotatably installed in the outer cylinder, and a sealing cavity is formed between the outer side wall thereof and the upper dynamic seal ring and the lower dynamic seal ring. A bearing is installed on the outer side wall of the rotating head corresponding to the sealing cavity; oil inlet ring grooves and oil return ring grooves are spaced apart along the axial direction of the outer side wall of the outer cylinder, an oil return port communicating with the sealing cavity is provided on the upper part of the inner side wall, an oil inlet port communicating with the sealing cavity is provided on the lower part, and an oil inlet channel communicating the oil inlet ring groove with the oil inlet port and an oil return channel communicating the oil return ring groove with the oil return port are provided inside the side wall.

[0009] An oil distribution assembly, the upper part of the oil distribution assembly is sleeved on the outer side wall of the outer cylinder, and the lower part is connected to the housing. An oil inlet hole communicating with the oil inlet ring groove and an oil return hole communicating with the oil return ring groove are provided on the upper part of the oil distribution assembly. The oil inlet hole communicates with an oil inlet pipe, and the oil return hole communicates with an oil return pipe.

[0010] The beneficial effects that the present invention can achieve: By providing an oil distribution assembly, connecting the oil inlet pipe and the oil return pipe to the oil distribution assembly, after the rotating assembly is installed, its oil inlet ring groove and oil return ring groove can be automatically communicated with the oil inlet pipe and the oil return pipe respectively through the oil distribution assembly, and the joints of the oil inlet pipe and the oil return pipe do not need to be disassembled and assembled, avoiding manual high-altitude operation, saving manpower, shortening the drilling stop time, improving production efficiency, and avoiding safety accidents.

[0011] Further, the oil distribution assembly includes an oil distribution ring and a plurality of oil distribution ring fixing members. The oil distribution ring is sleeved on the outer side wall of the outer cylinder, and an oil inlet hole communicating with the oil inlet ring groove and an oil return hole communicating with the oil return ring groove are provided on the oil distribution ring; the plurality of oil distribution ring fixing members are arranged at intervals along the circumferential direction of the oil distribution ring, and each oil distribution ring fixing member is connected to the bottom of the oil distribution ring at the top and has a limiting protrusion formed at the bottom. A limiting groove for limiting connection with each limiting protrusion is provided on the outer side wall of the housing.

[0012] Further, the limiting protrusion is fixed in the limiting groove by a screw.

[0013] Further, a clamp assembly is also provided. The clamp assembly includes an oil cylinder and a first clamp piece and a second clamp piece connected in a snap-on manner. One end of the first clamp piece is hingedly connected to the fixed end of the oil cylinder, one end of the second clamp piece is hinged to the other end of the first clamp piece, and the other end is hinged to the movable end of the oil cylinder;

[0014] The first clamp piece and the second clamp piece have the same structure. Through slots are respectively formed in the inner side walls corresponding to the oil distribution ring fixing parts, and a lower annular clamping protrusion is formed at the lower part of the inner side wall, and an upper annular clamping groove is formed at the upper part. A lower annular clamping groove for clamping and cooperating with the lower annular clamping protrusion is formed in the outer side wall of the housing above the limiting groove, and an upper annular clamping protrusion for clamping and cooperating with the upper annular clamping groove is formed on the outer side wall of the outer cylinder.

[0015] Further, the oil cylinder includes:

[0016] A cylinder barrel, the cylinder barrel is a cylindrical structure with both ends closed, a first oil port is opened at one end, and a second oil port is opened at the other end; the first clamp piece is hinged on the outer wall of the cylinder barrel near the second oil port end;

[0017] A piston assembly, one end of the piston assembly is slidably installed in the inner cavity of the cylinder barrel along the axial direction of the cylinder barrel, and the other end passes through the end of the other end of the cylinder barrel and is hinged to the second clamp piece.

[0018] Further, the piston assembly includes:

[0019] A piston rod, one end of the piston rod is slidably installed in the inner cavity of the cylinder barrel along the axial direction of the cylinder barrel, and the other end passes through the end wall of the cylinder barrel near the first oil port end and is hinged to the second clamp piece;

[0020] An outer sleeve, the outer sleeve is a cylindrical structure with both ends closed, it is fixed at one end of the piston rod corresponding to the inside of the cylinder barrel, and its outer side wall is slidably connected to the inner side wall of the cylinder barrel; a plurality of first oil holes are opened at one end of the outer sleeve near the first oil port, and a plurality of second oil holes are opened at one end near the second oil port; a plurality of sliding ports communicating with its inner cavity are circumferentially spaced on the side wall of the outer sleeve;

[0021] A wedge block pushing assembly, the wedge block pushing assembly is slidably installed in the inner cavity of the outer sleeve along the axial direction of the cylinder barrel;

[0022] A plurality of wedges are provided. On the inner side wall of the cylinder barrel, on the side close to the second oil port, there is a cylinder barrel inclined sliding surface with a gradually decreasing inner diameter in the direction away from the second oil port. The plurality of wedges correspond to the plurality of sliding ports one by one and are slidably installed in the sliding ports along the radial direction of the outer sleeve. On the side of each wedge away from the inner cavity of the outer sleeve, there is a first inclined sliding surface that can slidably cooperate with the cylinder barrel inclined sliding surface. On the side close to the inner cavity of the outer sleeve, each is connected to the output end of the wedge pushing assembly to slide along the radial direction of the outer sleeve under the drive of the wedge pushing assembly.

[0023] Furthermore, the wedge pushing assembly includes:

[0024] An inner piston, the inner piston includes a sealing section and an installation section with an outer diameter smaller than that of the sealing section. The installation section is slidably installed in the inner cavity of the outer sleeve along the axial direction of the outer sleeve. The sealing section is integrally connected to the side of the installation section close to the first oil hole, and a plurality of plunger installation holes arranged along the axial direction of the outer sleeve are circumferentially spaced on the outer peripheral side of the installation section corresponding to the installation section;

[0025] A wedge sleeve, the wedge sleeve is slidably sleeved on the outer side wall of the installation section along the axial direction of the outer sleeve. The wedge sleeve is circumferentially provided with a plurality of oil passing holes arranged along the axial direction of the outer sleeve, and on its outer side wall, there is a wedge sleeve inclined surface with a gradually increasing diameter in the direction close to the first oil hole. On the side of the wedge close to the inner cavity of the outer sleeve, there is a second inclined sliding surface that slidably cooperates with the wedge sleeve inclined surface;

[0026] A plurality of plungers, the plurality of plungers correspond to the plurality of plunger installation holes one by one and are slidably installed in the plunger installation holes along the axial direction of the outer sleeve. And the end of each plunger away from the first oil hole can abut against the end of the wedge sleeve close to the first oil hole.

[0027] Furthermore, a limiting retaining ring is fixed on the outer side wall of the installation section close to the second oil hole end. On the end face of the wedge sleeve close to the second oil hole end, there is a circular limiting groove opening penetrating its inner side wall. The limiting retaining ring can be clamped in the limiting groove opening.

[0028] Furthermore, the inclination angle of the wedge sleeve inclined surface is 10°.

[0029] Furthermore, a plurality of long strip-shaped chutes are arranged on the wedge sleeve inclined surface in the length direction along its axial direction. A plurality of sliding strips that slidably cooperate with the long strip-shaped chutes are formed on the second inclined sliding surface.

[0030] Through the above technical solutions, compared with the prior art, the present invention discloses and provides a wellhead non-disassembling and assembling type rotary blowout preventer, which has the following beneficial effects:

[0031] 1. By setting up the oil distribution assembly, after the rotary assembly is installed in place, automatic connection between the rotary assembly and the hydraulic circuit can be achieved, eliminating the need for manual repeated disassembly and assembly of the hydraulic pipeline, avoiding manual high-altitude operation, and improving production efficiency and work safety.

[0032] 2. Through the oil cylinder with an automatic locking function, the clamp assembly can be mechanically locked automatically when closed and unlocked automatically before opening, eliminating the need for manual disassembly and assembly of the locking bolts, avoiding manual high-altitude operation, saving manpower, and improving production efficiency and work safety. Brief Description of the Drawings

[0033] 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 use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative efforts.

[0034] Figure 1 It is a schematic diagram of the overall structure of a wellhead non-disassembling and assembling rotary blowout preventer provided by the present invention.

[0035] Figure 2 It is a schematic diagram of the exploded structure of a wellhead non-disassembling and assembling rotary blowout preventer provided by the present invention.

[0036] Figure 3 It is a schematic diagram of the sectional structure of a wellhead non-disassembling and assembling rotary blowout preventer provided by the present invention.

[0037] Figure 4 It is Figure 3 an enlarged schematic diagram of part A in

[0038] Figure 5 It is Figure 3 an enlarged schematic diagram of part B in

[0039] Figure 6 It is a schematic diagram of a sectional structure of the piston rod of the oil cylinder of the present invention in the retracted and locked state.

[0040] Figure 7 It is another schematic diagram of a sectional structure of the piston rod of the oil cylinder of the present invention in the retracted and locked state.

[0041] Figure 8 It is a schematic diagram of a sectional structure of the piston rod of the oil cylinder of the present invention when extended to the intermediate state.

[0042] Figure 9 It is another schematic diagram of a sectional structure of the piston rod of the oil cylinder of the present invention when extended to the intermediate state.

[0043] Figure 10 This is a schematic cross-sectional structure diagram of the fully extended state of the oil cylinder piston rod of the present invention.

[0044] Figure 11 This is another schematic cross-sectional structure diagram of the fully extended state of the oil cylinder piston rod of the present invention.

[0045] Figure 12 This is a schematic explosion structure diagram of the oil cylinder of the present invention.

[0046] Figure 13 This is a schematic structure diagram of the wedge sleeve of the present invention.

[0047] Figure 14 This is a schematic structure diagram of the wedge block of the present invention.

[0048] In the figure:

[0049] 1. Housing;

[0050] 2. Rotating assembly, 21. Outer cylinder, 211. Oil inlet ring groove, 212. Oil return ring groove, 213. Oil return port, 214. Oil inlet port, 215. Oil inlet channel, 216. Oil return channel, 22. Rotating head, 23. Upper dynamic seal ring, 24. Lower dynamic seal ring, 25. Bearing;

[0051] 3. Oil distribution assembly, 31. Oil distribution ring, 311. Oil inlet hole, 312. Oil return hole, 32. Oil distribution ring fixing part, 321. Limit projection;

[0052] 4. Clamp assembly, 41. Oil cylinder, 411. Cylinder barrel, 4111. Cylinder body, 41111. Cylinder barrel inclined sliding surface, 4112. First end cover, 41121. First oil port, 4113. Second end cover, 41131. Second oil port, 412. Piston rod, 4121. First shaft, 4122. Second shaft, 41221. Annular limit groove, 412211. Positioning block, 413. Outer sleeve, 4131, First sleeve, 41311. First oil hole, 4132. Second sleeve, 41321. Second oil hole, 41322. Slide port, 414. Wedge block, 4141. First inclined sliding surface, 4142. Second inclined sliding surface, 41421. Slide bar, 415. Inner piston, 4151. Sealing section, 41511. Plunger installation hole, 4152. Installation section, 4153. Limit retaining ring, 416. Wedge sleeve, 4161. Oil passing hole, 4162. Wedge sleeve inclined surface, 41621. Long strip-shaped chute, 417. Plunger, 42. First hoop, 43. Second hoop;

[0053] 5. Oil inlet pipe;

[0054] 6. Oil return pipe. Specific embodiments

[0055] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. 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.

[0056] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0057] In the present invention, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0058] Please refer to Figures 1-14 , an embodiment of the present invention discloses a wellhead non-disassembling rotary blowout preventer, including:

[0059] A housing 1; a central hole is provided at the top of the housing 1;

[0060] A rotary assembly 2, the rotary assembly 2 includes an outer cylinder 21 and a rotary head 22. The outer cylinder 21 is installed in the central hole. An upper dynamic seal ring 23 is installed on the inner wall of the upper end of the outer cylinder 21, and a lower dynamic seal ring 24 is installed on the inner wall of the lower end. The upper part of the rotary head 22 is rotatably installed in the outer cylinder 21, and a sealing cavity is formed between its outer side wall and the upper dynamic seal ring 23 and the lower dynamic seal ring 24. A bearing 25 is installed on the outer side wall of the rotary head 22 corresponding to the sealing cavity. Oil inlet ring grooves 211 and oil return ring grooves 212 are provided at intervals along the axial direction of the outer side wall of the outer cylinder 21. An oil return port 213 communicating with the sealing cavity is provided on the upper part of the inner side wall, and an oil inlet port 214 communicating with the sealing cavity is provided on the lower part. An oil inlet passage 215 communicating the oil inlet ring groove 211 and the oil inlet port and an oil return passage 216 communicating the oil return ring groove 212 and the oil return port are provided inside the side wall;

[0061] The oil distribution assembly 3 is sleeved on the outer side wall of the outer cylinder 21 at the upper part and fixedly connected to the housing 1 at the lower part. An oil inlet hole 311 communicating with the oil inlet ring groove 211 and an oil return hole 312 communicating with the oil return ring groove 212 are formed in the upper part of the oil distribution assembly 3. The oil inlet hole 311 communicates with the oil inlet pipe 5, and the oil return hole 312 communicates with the oil return pipe 6.

[0062] To further optimize the above technical solution, the oil distribution assembly 3 includes an oil distribution ring 31 and a plurality of oil distribution ring fixing members 32. The oil distribution ring 31 is sleeved on the outer side wall of the outer cylinder 21, and an oil inlet hole 311 communicating with the oil inlet ring groove 211 and an oil return hole 312 communicating with the oil return ring groove 212 are formed in the oil distribution ring 31. The plurality of oil distribution ring fixing members 32 are arranged at intervals along the circumferential direction of the oil distribution ring 31. Each oil distribution ring fixing member 32 is connected to the bottom of the oil distribution ring 31 at the top and has a limiting protrusion 321 formed at the bottom. A limiting groove for limiting connection with each limiting protrusion 321 is formed on the outer side wall of the housing 1. The oil distribution ring 31 is fixed to the housing 1 through the oil distribution ring fixing members 32, and the installation is firm.

[0063] To further optimize the above technical solution, the limiting protrusion 321 is fixed in the limiting groove by screws to strengthen the firmness of the installation of the oil distribution assembly 3.

[0064] To further optimize the above technical solution, a clamp assembly 4 is also provided. The clamp assembly 4 includes an oil cylinder 41 and a first clamp piece 42 and a second clamp piece 43 which are connected in a snap-on manner. One end of the first clamp piece 42 is hinged to the fixed end of the oil cylinder 41, one end of the second clamp piece 43 is hinged to the other end of the first clamp piece 42, and the other end is hinged to the movable end of the oil cylinder 41.

[0065] The first clamp piece 42 and the second clamp piece 43 have the same structure. A through slot is formed on the inner side wall corresponding to the oil distribution ring fixing member 32, and a lower annular clamping protrusion is formed at the lower part of the inner side wall, and an upper annular clamping groove is formed at the upper part. A lower annular clamping groove for clamping and cooperating with the lower annular clamping protrusion is formed on the outer side wall of the housing 1 above the limiting groove, and an upper annular clamping protrusion for clamping and cooperating with the upper annular clamping groove is formed on the outer side wall of the outer cylinder 21. The outer cylinder 21 and the housing 1 are locked through the clamp assembly 4.

[0066] To further optimize the above technical solution, the oil cylinder 41 includes:

[0067] A cylinder barrel 411, the cylinder barrel 411 has a cylindrical structure with both ends closed. A first oil port 41121 is formed at one end, and a second oil port 41131 is formed at the other end. The first clamp piece 42 is hinged to the outer wall of the cylinder barrel 411 near the second oil port 41131.

[0068] A piston assembly, one end of the piston assembly is slidably installed in the inner cavity of the cylinder barrel 411 along the axial direction of the cylinder barrel 411, and the other end passes through the end of the other end of the cylinder barrel 411 and is hinged to the second clamp piece 43.

[0069] The cylinder barrel 411 includes a cylinder body 4111, a first end cover 4112 and a second end cover 4113 respectively installed at both ends of the cylinder body. A first oil port 41121 is opened on the first end cover 4112, and a second oil port 41131 is opened on the second end cover 4113. The first hoop 42 is hinged to the second end cover 4113;

[0070] In the prior art, the hydraulic cylinder only relies on the pressure of the hydraulic oil to push the piston rod to move, and after the piston rod slides in place, it is necessary to maintain the stability of the hydraulic oil pressure to ensure that the piston rod stops at the set position. Once the hydraulic oil changes, the piston will slide, resulting in the possibility that the clamp may not be tightened. Therefore, in order to further optimize the above technical solution, the piston assembly includes:

[0071] A piston rod 412, one end of the piston rod 412 is slidably installed in the inner cavity of the cylinder barrel 411 along the axial direction of the cylinder barrel 411, and the other end passes through the end wall of the cylinder barrel 411 near the first oil port 41121 and is hinged to the second hoop 43;

[0072] An outer sleeve 413, the outer sleeve 413 has a cylindrical structure with both ends closed, which is fixed at one end of the piston rod 412 corresponding to the inside of the cylinder barrel 411, and its outer side wall is slidably connected to the inner side wall of the cylinder barrel 411; a plurality of first oil holes 41311 are opened at one end of the outer sleeve 413 near the first oil port 41121, and a plurality of second oil holes 41321 are opened at one end near the second oil port 41131; a plurality of sliding ports 41322 communicating with its inner cavity are circumferentially spaced on the side wall of the outer sleeve 413;

[0073] A wedge block pushing assembly, the wedge block pushing assembly is slidably installed in the inner cavity of the outer sleeve 413 along the axial direction of the cylinder barrel 411;

[0074] A plurality of wedge blocks 414, on the inner side wall of the cylinder body 4111 near the second oil port 41131, there is a cylinder barrel inclined sliding surface 41111 with an inner diameter gradually decreasing in the direction away from the second oil port 41131. The plurality of wedge blocks 414 correspond to the plurality of sliding ports 41322 one by one and are slidably installed in the sliding ports 41322 along the radial direction of the outer sleeve 413. And on the side of each wedge block 414 away from the inner cavity of the outer sleeve 413, there is a first inclined sliding surface 4141 that can slidably cooperate with the cylinder barrel inclined sliding surface 41111, and the side near the inner cavity of the outer sleeve 413 is connected to the output end of the wedge block pushing assembly to slide along the radial direction of the outer sleeve 413 under the drive of the wedge block pushing assembly.

[0075] The piston rod 412 is a stepped shaft, which includes a first shaft 4121 and a second shaft 4122 with an outer diameter smaller than that of the first shaft 4121. One end of the first shaft 4121 is hinged to the second hoop 43, and the other end is integrally connected to the second shaft 4122, and a shoulder is formed at the connection with the second shaft 4122. An annular limiting groove 41221 is formed on the side wall of the other end of the second shaft 4122. The outer sleeve 413 is sleeved on the second shaft 4122, and the end face of one end thereof abuts against the shoulder, and a limiting ring that is clamped with the annular limiting groove 41221 is arranged at the other end.

[0076] To further optimize the above technical solution, the outer sleeve 413 includes a first sleeve 4131 and a second sleeve 4132. Both the first sleeve 4131 and the second sleeve 4132 are cylindrical structures with one end open. The first sleeve 4131 and the second sleeve 4132 are arranged with their openings facing each other. The first sleeve 4131 is sleeved on the second shaft 4122 and the closed end thereof abuts against the shoulder. A plurality of first oil holes 41311 are circumferentially and spacedly arranged on the closed end of the first sleeve 4131. The open end of the second sleeve 4132 abuts against the end wall of the open end of the first sleeve 4131. A plurality of second oil holes 41321 are circumferentially and spacedly formed on the closed end. The limiting ring 41323 is arranged at the closed end of the second sleeve 4132, and a plurality of sliding openings 41322 are circumferentially and spacedly arranged on the side wall of the second sleeve 4132.

[0077] A plurality of positioning blocks 412211 are circumferentially and fixedly arranged at the bottom of the annular limiting groove 41221. A plurality of positioning grooves that are positioned and connected with the positioning blocks 412211 are circumferentially arranged on the limiting ring 41323 to prevent relative rotation between the outer sleeve 413 and the piston rod.

[0078] To further optimize the above technical solution, the second sleeve 4132 is formed by circumferentially splicing a plurality of arc-shaped structural plates, so as to facilitate sleeving the second sleeve 4132 on the second shaft 4122.

[0079] To further optimize the above technical solution, the wedge block pushing assembly includes:

[0080] An inner piston 415, the inner piston 415 includes a sealing section 4151 and an installation section 4152 with an outer diameter smaller than that of the sealing section 4151. The installation section 4152 is slidably installed in the inner cavity of the outer sleeve 413 along the axial direction of the outer sleeve 413. The sealing section 4151 is integrally connected to the side of the installation section 4152 close to the first oil holes 41311, and a plurality of plunger installation holes 41511 arranged along the axial direction of the outer sleeve 413 are circumferentially spaced on the outer peripheral side of the installation section 4152 corresponding to the sealing section 4151. Among them, both the sealing section 4151 and the installation section 4152 are sleeve-shaped structures and can be slidably sleeved on the second shaft 4122 to improve the stability of the inner piston 415 during the sliding process.

[0081] The wedge sleeve 416 is slidably sleeved on the outer sidewall of the installation section 4152 along the axial direction of the outer sleeve 413. A plurality of oil passing holes 4161 arranged along the axial direction of the outer sleeve 413 are circumferentially spaced on the wedge sleeve 416, and a wedge sleeve inclined surface 4162 with a gradually increasing diameter towards the first oil hole 41311 is provided on its outer sidewall. A second inclined sliding surface 4142 slidably engaged with the wedge sleeve inclined surface 4162 is provided on the side of the wedge block 414 close to the inner cavity of the outer sleeve 413.

[0082] A plurality of plungers 417 are slidably installed in the plunger installation holes 41511 along the axial direction of the outer sleeve 413, corresponding to the plurality of plunger installation holes 41511 one by one, and one end of each plunger 417 away from the first oil hole 41311 can abut against the end of the wedge sleeve 416 close to the first oil hole 41311.

[0083] To further optimize the above technical solution, a limit retaining ring 4153 is fixed on the outer sidewall of the installation section 4152 close to one end of the second oil hole 41321. An annular limit notch penetrating through its inner sidewall is formed on the end surface of the wedge sleeve 416 close to one end of the second oil hole 41321. The limit retaining ring 4153 can be clamped in the limit notch to limit the wedge sleeve 416, so that the wedge sleeve 416 can slide together with the inner piston.

[0084] To further optimize the above technical solution, the inclination angle of the wedge sleeve inclined surface 4162 is preferably 10°. Self-locking among the wedge block 414, the wedge sleeve 416 and the cylinder barrel 411 is achieved.

[0085] To further optimize the above technical solution, as Figures 12-14 shown, a plurality of elongated sliding grooves 41621 arranged along the axial direction of the wedge sleeve inclined surface 4162 are formed on the wedge sleeve inclined surface 4162, and a plurality of sliding strips 41421 slidably engaged with the elongated sliding grooves 41621 are formed on the second inclined sliding surface 4142. It is ensured that the wedge block 414 can only slide along the axial direction of the cylinder barrel 411. At the same time, the toothed sliding fit structure formed by the plurality of sliding strips 41421 and the plurality of elongated sliding grooves 41621 increases the contact area between the wedge sleeve 416 and the wedge block 414 and increases the friction force, so as to achieve self-locking at a larger inclination angle, shorten the stroke and make the structure more compact.

[0086] Working principle:

[0087] Before the equipment works, it needs to be installed at the wellhead. During installation, except for the rotating assembly 2, other components are installed on the wellhead drilling equipment as a whole. After the equipment is in place, the oil pipeline of the oil cylinder 41 and the oil distribution assembly 3 is installed well. The state of the rotating assembly 2 during the lowering of the drill tool to be installed in place is as Figure 2As shown, at this time, the piston rod 412 of the oil cylinder 41 is in the extended state, which drives the clamp assembly 4 to be in the open state. When the rotating assembly 2 continues to fall, its front end will pass through the oil distribution assembly 3 and the clamp assembly 4 and abut against the housing 1;

[0088] After the rotating assembly 2 falls in place, operate the hydraulic equipment to retract the piston rod 412 of the oil cylinder 41, driving the clamp assembly 4 to close to clamp the rotating assembly 2. At this time, the positions of all components are as Figure 1 shown;

[0089] After the rotating assembly 2 is installed in place, the oil circuit inside it is automatically connected through the oil distribution ring 31, and there is no need for manual connection. The oil circuit direction is as follows: The oil in the inlet pipe enters through the oil inlet hole 311, enters the oil inlet ring groove 211 through the oil inlet hole 311, then enters the sealing cavity through the oil inlet 214, flows upward from the bottom of the rotating control assembly through all bearings 25, cools and lubricates the bearings 25, and then enters the oil return ring groove 212 through the oil return port 213, and then flows to the oil return pipe through the oil return hole 312.

[0090] When it is necessary to lift the rotating assembly 2 for replacing vulnerable parts, the oil circuit will be interrupted. To reduce environmental pollution and waste of resources, after the machine is stopped, first use the method of blowing and squeezing with compressed air to drain the oil stored in the inner cavity of the rotating assembly 2 into the fuel tank, and then perform the operations of opening the clamp assembly 4 and lifting the rotating assembly 2.

[0091] After the oil cylinder 41 retracts the piston rod 412 to close the clamp assembly 4, it can automatically achieve mechanical locking at this position. At this time, even if the hydraulic pressure disappears, the piston rod 412 will not become loose. It is necessary to operate the reverse oil pressure to unlock the internal mechanism before the piston rod 412 can extend, so that this mechanism no longer requires manual locking, realizing the function of no need to disassemble and assemble at the wellhead;

[0092] Figure 6 、 Figure 7It is a sectional view when the piston rod of the oil cylinder 41 is in the automatically locked state after retraction. The working principle is as follows: The pressure oil enters the rod chamber through the first oil port 41121. The piston rod 412 retracts, driving the clamp assembly 4 to close. The pressure oil in the rod chamber enters the inner cavity of the outer sleeve 413 through the first oil hole 41311 on the outer sleeve 413, acting on the end face of the sealing section 4151 of the inner piston 415, and pushing the inner piston 415 to move left until the end face of the installation section 4152 of the inner piston 415 abuts against the inner end wall of the outer sleeve 413. During the leftward movement of the inner piston 415, the end face of the wedge sleeve 416 abuts against the side of the sealing section 4151 away from the rod chamber, and the pressure oil does not contact the wedge sleeve 416, so that there is no relative movement between the wedge sleeve 416 and the inner piston 415. When the inner piston 415 moves to the left end and abuts against the end wall of the cylinder barrel 411, the pressure oil cannot continue to push the inner piston 415 to move left. At this time, the pressure oil acts on the plunger 417, pushing the plunger 417 to move left. The leftward movement of the plunger 417 pushes the wedge sleeve 416 to move left. Since the wedge block 414 is movably installed in the sliding port and is restricted by the sliding port to move only radially, when the wedge sleeve 416 moves left, under the cooperation of the second inclined sliding surface 4142 and the wedge sleeve inclined surface 4162, it will cause the wedge block 414 to expand radially outward until the first inclined sliding surface 4141 of the wedge block 414 abuts against the cylinder barrel inclined sliding surface 41111. Since the second inclined surface and the wedge sleeve inclined surface 4162 are self-locking inclined angles, at this time, the wedge block 414, the cylinder barrel inclined sliding surface 41111 and the wedge sleeve inclined surface 4162 form a self-locking inclined surface mechanism. At this time, even if the hydraulic pressure disappears, the reaction force from the piston rod 412 to the right acts on the outer sleeve 413. Due to the self-locking state of the mechanism, the outer sleeve 413 will not move right, so the piston rod 412 will not move right, and the clamp assembly hinged to the piston rod 412 will not loosen. The piston rod 412 is in a mechanically locked state at this position.

[0093] When it is necessary to open the clamp assembly, it is necessary to operate the reversing valve to reverse the oil path of the oil cylinder 41. At this time, the pressure oil enters the rodless chamber of the cylinder barrel 411 through the second oil port 41131, and the oil in the rod chamber returns to the fuel tank through the second oil port 41131. As Figure 8 、 Figure 9, The pressurized oil enters the inner cavity of the outer sleeve 413 through the second oil hole 41321 and acts on the inner piston 415 to move the inner piston 415 to the right. Since the limit retaining ring 4153 on the inner piston 415 is clamped with the annular limit notch on the wedge sleeve 416, when the inner piston 415 continues to move to the right, it will pull the wedge sleeve 416 to move to the right together until the sealing section 4151 abuts against the inner end face of the outer sleeve 413. At this time, the wedge block 414 is no longer under the expansion action of the wedge sleeve 416 and can retract into the inner cavity of the outer sleeve 413 along the sliding opening. As shown in the figure, the piston assembly completes the unlocking of the mechanism. Under the action of the oil pressure, the piston assembly continues to move to the right until the piston rod 412 completely extends, and the clamp assembly hinged to the piston rod 412 is also completely opened. When the piston rod 412 completely extends, the state of its internal components is as Figure 10 , Figure 11 shown;

[0094] When the reversing valve is operated again to reverse the oil circuit and perform the operation of closing the clamp assembly, the state of the internal components of the piston assembly is as Figure 6 , Figure 7 shown. The pressurized oil enters the rod chamber through the first oil port 41121, pushing the piston assembly to complete self-locking, retracting the piston rod 412 and achieving mechanical locking.

[0095] During the mechanical locking process, the driving force for the movement of the wedge sleeve 416 comes from the driving force of the plunger 417. Since the diameter of the plunger 417 is small, the locking force generated by it is small, and the small force can reduce the wear of the components during movement; when the mechanism is unlocked, the driving force for the movement of the wedge sleeve 416 comes from the driving force of the inner piston 415. Compared with when the pressurized oil acts on the end face of the plunger 417, when the pressurized oil acts on the end face of the inner piston 415, its acting area is larger and the unlocking force provided is also larger, thus avoiding unlocking failure and improving the reliability of the mechanism.

[0096] After the rotating blowout preventer of the present invention is installed in place, during the entire working period, when it is necessary to lift the rotating assembly 2 to replace the vulnerable parts and lower the rotating assembly 2 for installation, the oil distribution assembly 3 can realize the automatic connection of the hydraulic circuit, and the clamp assembly 4 can also be automatically unlocked and locked through the oil cylinder 41, eliminating the need for manual high-altitude disassembly and assembly operations at the wellhead, achieving manual-free disassembly and assembly, and greatly improving the production efficiency and work safety.

[0097] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0098] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wellhead non-disassembly type rotary blowout preventer, characterized in that: include: A shell (1); a center hole is formed on the top of the shell (1); The rotating assembly (2) comprises an outer cylinder (21) and a rotating head (22), wherein the outer cylinder (21) is installed in the center hole, an upper dynamic sealing ring (23) is installed on the inner wall of the upper end of the outer cylinder (21), and a lower dynamic sealing ring (24) is installed on the inner wall of the lower end of the outer cylinder (21), and the upper part of the rotating head (22) is rotatably installed in the outer cylinder (21), and a sealing cavity is formed between the outer wall of the rotating head (22) and the upper dynamic sealing ring (23) and the lower dynamic sealing ring (24), and the outer wall of the rotating head (22) is installed at a position corresponding to the sealing cavity. A bearing (25) is installed; an outer wall of the outer cylinder (21) is provided with an oil inlet ring groove (211) and an oil return ring groove (212) spaced apart in the axial direction thereof; an upper portion of the inner wall is provided with an oil return port (213) connected to the sealing cavity; a lower portion is provided with an oil inlet port (214) connected to the sealing cavity; and an oil inlet passage (215) connecting the oil inlet ring groove (211) and the oil inlet port (214) and an oil return passage (216) connecting the oil return ring groove (212) and the oil return port (213) are provided inside the side wall; An oil distribution assembly (3), wherein the upper portion of the oil distribution assembly (3) is sleeved on the outer side wall of the outer cylinder (21), and the lower portion is connected to the housing (1); the upper portion of the oil distribution assembly (3) is provided with an oil inlet hole (311) connected to the oil inlet ring groove (211) and an oil return hole (312) connected to the oil return ring groove (212); the oil inlet hole (311) is connected to the oil inlet pipe (5), and the oil return hole (312) is connected to the oil return pipe (6).

2. A wellhead non-disassembly type rotary blowout preventer according to claim 1, characterized in that: The oil distribution assembly (3) comprises an oil distribution ring (31) and a plurality of oil distribution ring fixing members (32); the oil distribution ring (31) is sleeved on the outer wall of the outer cylinder (21), and the oil distribution ring (31) is provided with an oil inlet hole (311) connected to the oil inlet ring groove (211) and an oil return hole (312) connected to the oil return ring groove (212); the plurality of oil distribution ring fixing members (32) are arranged at intervals along the circumferential direction of the oil distribution ring (31), and the top of each of the oil distribution ring fixing members (32) is connected to the bottom of the oil distribution ring (31), and a limiting protrusion (321) is formed on the bottom; and a limiting groove corresponding to each limiting protrusion (321) and connected to the limiting protrusion (321) is provided on the outer wall of the housing (1).

3. A wellhead non-disassembly type rotary blowout preventer according to claim 2, characterized in that: The limiting protrusion (321) is fixed in the limiting groove by means of screws.

4. The wellhead non-disassembly type rotary blowout preventer according to claim 2, characterized in that: A clamp assembly (4) is also provided, the clamp assembly (4) comprising an oil cylinder (41) and a first hoop piece (42) and a second hoop piece (43) connected in a buckle-type manner, one end of the first hoop piece (42) being hingedly connected to a fixed end of the oil cylinder (41), one end of the second hoop piece (43) being hingedly connected to the other end of the first hoop piece (42), and the other end being hingedly connected to a movable end of the oil cylinder (41); The first hoop plate (42) and the second hoop plate (43) have the same structure, and a through-notch is formed on the inner wall thereof corresponding to the oil distribution ring fixing member (32), and a lower annular clamping protrusion is formed on the lower part of the inner wall thereof, and an upper annular clamping groove is formed on the upper part thereof, and a lower annular clamping groove is formed on the outer wall of the housing (1) corresponding to the upper part of the limit groove and is engaged with the lower annular clamping protrusion, and an upper annular clamping protrusion is formed on the outer wall of the outer cylinder (21) and is engaged with the upper annular clamping groove.

5. The wellhead non-disassembly type rotary blowout preventer according to claim 4, characterized in that: The oil cylinder (41) comprises: A cylinder barrel (411), the cylinder barrel (411) being a cylindrical structure with both ends closed, a first oil port (41121) being provided at one end thereof, and a second oil port (41131) being provided at the other end thereof; the first hoop (42) being hingedly connected to an outer wall of the cylinder barrel (411) at one end thereof close to the second oil port (41131); A piston assembly, one end of which is slidably mounted in the inner cavity of the cylinder (411) along the axial direction of the cylinder (411), and the other end of which passes through the end of the other end of the cylinder (411) and is hinged to the second hoop (43).

6. The wellhead non-disassembly type rotary blowout preventer according to claim 5, characterized in that: The piston assembly comprises: a piston rod (412), one end of the piston rod (412) being slidably mounted in the inner cavity of the cylinder barrel (411) along the axial direction of the cylinder barrel (411), and the other end of the piston rod (412) passing through an end wall of the cylinder barrel (411) close to one end of the first oil port (41121) and being hingedly connected to the second hoop plate (43); An outer sleeve (413), the outer sleeve (413) being a cylindrical structure with both ends closed, fixed to one end of the piston rod (412) corresponding to the cylinder (411), and having an outer wall slidably connected to the inner wall of the cylinder (411); a plurality of first oil holes (41311) are provided at one end of the outer sleeve (413) close to the first oil port (41121), and a plurality of second oil holes (41321) are provided at one end of the outer sleeve (413) close to the second oil port (41131); a plurality of sliding openings (41322) communicating with the inner cavity thereof are circumferentially spaced apart on the side wall of the outer sleeve (413); a wedge pushing assembly, the wedge pushing assembly being slidably mounted in the inner cavity of the outer sleeve (413) along the axial direction of the cylinder (411); A plurality of wedge blocks (414) are provided, on the side of the inner wall of the cylinder (411) close to the second oil port (41131), with a cylinder inclined sliding surface (41111) whose inner diameter gradually decreases in the direction away from the second oil port (41131); the plurality of wedge blocks (414) correspond one-to-one to the plurality of sliding ports (41322) and are slidably installed in the sliding ports (41322) along the radial direction of the outer sleeve (413); a first inclined sliding surface (4141) slidably matched with the cylinder inclined sliding surface (41111) is provided on the side away from the inner cavity of the outer sleeve (413); and the side close to the inner cavity of the outer sleeve (413) is connected to the output end of the wedge block pushing assembly so as to slide along the radial direction of the outer sleeve (413) under the drive of the wedge block pushing assembly.

7. The wellhead non-disassembly type rotary blowout preventer according to claim 6, characterized in that: The wedge block pushing assembly comprises: an inner piston (415), the inner piston (415) comprising a sealing section (4151) and a mounting section (4152) having an outer diameter smaller than that of the sealing section (4151); the mounting section (4152) is slidably mounted in the inner cavity of the outer sleeve (413) along the axial direction of the outer sleeve (413); the sealing section (4151) is integrally connected to a side of the mounting section (4152) close to the first oil hole (41311); and a plurality of plunger mounting holes (41511) arranged along the axial direction of the outer sleeve (413) are circumferentially spaced apart on the outer circumferential side of the sealing section (4151) corresponding to the mounting section (4152); A wedge sleeve (416), the wedge sleeve (416) being slidably sleeved on the outer wall of the mounting section (4152) along the axial direction of the outer sleeve (413), the wedge sleeve (416) being provided with a plurality of oil holes (4161) arranged along the axial direction of the outer sleeve (413) at intervals in the circumferential direction, and a wedge sleeve inclined surface (4162) whose diameter gradually increases in a direction approaching the first oil hole (41311) being provided on the outer wall thereof, and a second inclined sliding surface (4142) being slidably matched with the wedge sleeve inclined surface (4162) being provided on a side of the wedge block (414) close to the inner cavity of the outer sleeve (413); A plurality of plungers (417), the plurality of plungers (417) corresponding one to one with the plurality of plunger mounting holes (41511) and slidably mounted in the plunger mounting holes (41511) along the axial direction of the outer sleeve (413), and an end of each plunger (417) away from the first oil hole (41311) abuts against an end of the wedge sleeve (416) close to the first oil hole (41311).

8. The wellhead non-disassembly type rotary blowout preventer according to claim 7, characterized in that: A limit stop ring (4153) is fixed on the outer wall of the mounting section (4152) near the second oil hole (41321), and an annular limit groove is provided on the end surface of the wedge sleeve (416) near the second oil hole (41321) and passes through the inner wall thereof, and the limit stop ring (4153) is clamped in the limit groove.

9. The wellhead non-disassembly type rotary blowout preventer according to claim 7, characterized in that: The inclination angle of the wedge sleeve inclined surface (4162) is 10°.

10. The wellhead non-disassembly type rotary blowout preventer according to claim 7, characterized in that: The wedge sleeve inclined surface (4162) is provided with a plurality of long strip sliding grooves (41621) arranged along its axial direction in the length direction, and the second inclined sliding surface (4142) is formed with a plurality of sliding strips (41421) that slidably cooperate with the long strip sliding grooves (41621).

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