Wellhead casing head

Abstract

The present invention discloses a wellhead casing head, and relates to the technical field of casing heads. The wellhead casing head comprises a flange housing, a slip hanger and a locking mechanism; the slip hanger comprises a support seat located at the bottom of the slip hanger, the support seat comprises a circular ring structure formed by two semi-annular structures, a lower end of each support seat is provided with a lower extension, and at least two outwardly radiating wedge plates are installed in each lower extension through a first spring, and the wellhead casing head is provided with a wedge plate connected by a first spring below the support seat of the hanger, so that the support of a C-shaped plate is not required, and the locking mechanism can also be unlocked. After it is unlocked, when a blowout preventer group is used to apply downward pressure to the slip hanger, the main limit guide groove will generate a large pressure on the wedge plate, so that the wedge plate can be stably moved downward along the main limit guide groove, so as to achieve the purpose of stable downward movement of the slip hanger, and avoid eccentricity of the slip hanger and the oil layer casing relative to the flange housing.

Description

Technical Field

[0001] The invention relates to the technical field of casing heads, in particular to a wellhead casing head. Background Art

[0002] The casing head is used to fix the wellhead of the drilled well, connect the wellhead casing string, support the gravity of the technical casing and the oil layer casing, seal the annular space between the layers of pipes, provide a transition connection for the installation of the blowout preventer, tubing head, and Christmas tree, and through the two side ports on the casing head body, operations such as squeezing mud, monitoring, and adding balancing fluid can be carried out.

[0003] The casing head generally includes a flange housing and a hanger. The hanger generally includes a slip hanger and an axis hanger. It is an important component used to hang the pipe string in oil and gas drilling operations. The slip hanger is mainly composed of a slip seat and a slip tooth. Among them, the slip tooth is the most critical component, which directly affects the clamping state of the slip tooth and the pipe string and the degree of damage to the pipe string.

[0004] When installing the hanger, refer to Figure 1 First, it is necessary to arrange two C-shaped plates 100 on the upper surface of the flange body to support the hanger to be assembled. The operator can operate the hanger through the support of the C-shaped plate 100. After the hanger is rotated into place, the entire hanger is pried up at the bottom of the hanger by two sets of crowbars, and then the two C-shaped plates 100 at the bottom are pulled out, and then the hanger is slowly pulled out and released by the two sets of crowbars until the hanger is lowered to pass through the inside of the flange shell.

[0005] However, the above operation process has certain defects:

[0006] Since the crowbar cannot completely enter the interior of the flange shell, it is pulled out earlier than the hanger. As a result, in the process of the hanger descending into the flange shell, the hanger itself and the oil layer casing have large deviations and inclinations. It is difficult for the two to maintain a concentric state with the flange shell, and the staff themselves need to perform extensive straightening to make the hanger itself and the oil layer casing concentric with the flange shell. Summary of the invention

[0007] In view of the deficiencies of the prior art, the present invention provides a wellhead casing head, which solves the problem that the hanger itself and the oil layer casing have large deviations and inclinations, and it is difficult for both to maintain concentricity with the flange housing.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: a wellhead casing head, comprising a flange shell, a slip hanger and a locking mechanism; the slip hanger comprises a support seat located at the bottom of the slip hanger, the support seat comprises a circular ring structure formed by two semi-annular structures, the lower end of each support seat is provided with a lower extension, each of the lower extensions is provided with at least two outwardly radiating wedge plates installed in it through a first spring, and the wedge plates can be retracted into the lower extension or ejected out of the lower extension by the first spring, and the bottom surface of the wedge plates is provided with There is a bottom slope; the inner edge of the upper end opening of the flange shell is provided with a slope mouth, and the inner wall of the flange shell is provided with a main limit guide groove from the slope mouth downward, and the main limit guide groove is opposite to the position of the wedge plate; the locking mechanism is arranged on the lower extension part, and the locking mechanism is used to lock or unlock the position of the wedge plate, the locking mechanism locks the wedge plate, and is used to make the wedge plate be located in the main limit guide groove on the slope mouth, forming a state in which the slip hanger is supported on the upper end of the flange shell, and the locking mechanism enables the wedge plate to be stably moved downward along the main limit guide groove when the wedge plate is unlocked.

[0009] Furthermore, a receiving groove is provided in the area opposite to the wedge plate on the lower extension portion, a mounting shell is fixed in the receiving groove, the locking mechanism is provided in the mounting shell, and the mounting shell has a sliding chamber capable of sliding the wedge plate, and the first spring is located in the sliding chamber; the locking mechanism comprises: a locking block, the locking block is located in the area close to the outer edge of the sliding chamber, and the locking block can move in the vertical direction, so that the locking block can block the wedge plate from retracting into the mounting shell or the locking block does not block the wedge plate from retracting into the mounting shell; a minor arc ring, two minor arc rings are provided, which are rotatably assembled on one side of the mounting shell close to the center of the cava hanger, and a rotating channel for the minor arc ring to rotate is provided in the mounting shell; a driving structure, the driving structure is used to drive the minor arc ring to rotate; a transmission structure, the transmission structure is used to convert the rotational force of the minor arc ring into the force required for the vertical displacement of the locking block.

[0010] Furthermore, the transmission structure includes: a sliding rod, one end of which is fixed on a locking block, a rotating cylinder is installed in the mounting shell at a position opposite to the other end of the sliding rod through rotation of a wheel axle, a spiral groove matching the sliding rod is provided on the outer arc surface of the rotating cylinder, and the sliding rod can be driven to produce vertical displacement when the rotating cylinder rotates, and a guide rod for guiding the sliding rod is provided in the mounting shell; a rotating gear, which is fixed on the wheel axle, and the outer surface of the minor arc ring is provided with a tooth portion meshing with the rotating gear, so that the minor arc ring can drive the rotating gear to rotate when it rotates.

[0011] Furthermore, the driving structure is arranged at one end where the two inferior arc rings are close to each other; the driving structure includes: a worm wheel, which is fixed on two wheel axles close to the end of the inferior arc ring; a worm, which is meshed on one side of the worm wheel, and a transmission gear is fixed on the end of the worm away from the center of the cava hanger, and the two transmission gears are meshed, and a through opening is opened on the mounting shell at a position opposite to the transmission gear, so that when the two lower extensions are matched, the two transmission gears can mesh with each other through the two through openings; a force hole, which is opened at one end of one of the worms away from the center of the lower extension, and the inner cavity of the force hole is a hexagonal groove, and an operating hole is opened in the area of ​​the lower extension opposite to the force hole.

[0012] Furthermore, the transmission structure includes a force-bearing rod, which is fixedly connected to a locking block, and the middle part of the force-bearing rod is sleeved in a force-bearing plate, the force-bearing plate is fixedly arranged in an installation shell, a second spring is provided on the upper part of the force-bearing plate, and the second spring is sleeved on the outside of the force-bearing rod, the second spring is arranged between the top of the force-bearing rod and the force-bearing plate, when the second spring is in a natural state, the locking block is upwardly disengaged from the sliding space, and when the second spring is under pressure, the locking block is inserted into the sliding space; an auxiliary ring is provided on the side of the force-bearing rod away from the wedge plate, and a lower convex portion is provided on the lower surface of the auxiliary ring, and a connecting rod 1 is fixed between the minor arc ring and the auxiliary ring, and when the minor arc ring rotates, the auxiliary ring can be caused to rotate so that the lower convex portion gradually presses down the force-bearing rod.

[0013] Furthermore, the outer surfaces of the ends of the two inferior arc rings that are close to each other are both provided with teeth, and the outer sides of the teeth are meshed with rotating gears, and the rotating gears are installed in the mounting shell through the rotation of the wheel axle; the driving structure includes: a worm wheel, which is fixed on the wheel axle; a worm, which is meshed on one side of the worm wheel, and a transmission gear is fixed on the end of the worm away from the center of the cava hanger, and the two transmission gears are meshed, and a through opening is opened at a position opposite to the transmission gear on the mounting shell, so that when the two lower extensions are matched, the two transmission gears can mesh with each other through the two through openings; a force hole, which is fixed on one of the transmission gears, and the inner cavity of the force hole is a hexagonal groove, and an operating hole is opened in the area opposite to the force hole on the lower extension.

[0014] Furthermore, the upper and lower surfaces of the wedge plate are provided with limiting grooves, and the upper and lower surfaces of the mounting shell are fixed with limiting protrusions, and the limiting protrusions cooperate with the limiting grooves to limit the limiting grooves from excessively extending out of the mounting shell.

[0015] Furthermore, the cava hanger also includes: a cava shell, the cava shell is composed of two semi-annular structures, and an extrusion chamber is provided in the cava shell, the lower end of the cava shell is provided with a cava seat composed of two semi-annular structures, the support seat is provided at the lower end of the cava seat, and the cava hanger is in a separable state when the connecting seam of the cava shell is aligned with the connecting seam of the support seat; cava teeth are provided in the extrusion chamber, and the cava teeth are provided in at least four groups, and the four groups of cava teeth are evenly distributed in the extrusion chamber, and the cava teeth can move downward when subjected to downward pressure, and the extrusion chamber can reduce the diameter of the cava teeth so that the cava teeth can hold the oil layer casing tightly.

[0016] Furthermore, the upper part of the flange shell is the flange disc body, and the lower part of the flange shell is the connecting pipe part. A retaining slope is provided inside the connecting pipe part, and the outer edge of the lower end of the support seat is provided with a slope surface adapted to the retaining slope, so that the retaining slope can support the cava hanger after the cava hanger moves down into the flange shell.

[0017] Furthermore, the four sides of the flange body are provided with top screw holes, and a pressure cap hole is provided on the side of the top screw hole away from the center of the flange shell; a top screw is provided in the top screw hole, and a conical structure is provided at the end of the top screw close to the center of the flange shell, so that the top screw can exert downward pressure on the cava tooth when it is pushed into the flange shell; a pressure cap is provided on the side of the top screw away from the center of the flange shell, and the pressure cap is located in the pressure cap hole.

[0018] The present invention has the following beneficial effects:

[0019] (1) The wellhead casing head has a wedge plate connected by a first spring disposed below the support seat of the hanger, and a slope opening is disposed on the inner edge of the upper end opening of the flange shell. A main limit guide groove is disposed downward from the slope opening on the inner wall of the flange shell, and the main limit guide groove is opposite to the position of the wedge plate. Therefore, when the wedge plate extends out of the outer periphery of the hanger, it can support the entire slip hanger above the flange shell, thereby eliminating the need for support by a C-shaped plate. In addition, since a locking mechanism capable of locking the position of the wedge plate is disposed, the wedge plate can be locked in the main limit guide groove on the slope opening and can maintain a stable support state.

[0020] (2) The locking mechanism of the wellhead casing head can also be unlocked. After being unlocked, the slip hanger can still be supported on the upper surface of the flange shell due to the elastic force of the first spring. However, when the blowout preventer group is used to apply downward pressure to the slip hanger, the main limit guide groove will exert a greater pressure on the wedge plate, so that the wedge plate can move downward stably along the main limit guide groove, thereby achieving the purpose of stable downward movement of the slip hanger and avoiding eccentricity of the slip hanger and the oil layer casing relative to the flange shell.

[0021] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of two C-shaped plates supporting the slip hanger above the flange housing in the prior art;

[0023] Figure 2 It is a schematic diagram of the slip hanger supported above the flange housing in the present invention;

[0024] Figure 3 For the present invention Figure 2 sectional view of

[0025] Figure 4 It is a schematic diagram of the overlap of the slip housing and the support seat of the slip hanger of the present invention;

[0026] Figure 5 The present invention is Figure 4 Separate schematic diagram;

[0027] Figure 6 A schematic diagram of the slip housing and the support seat of the slip hanger of the present invention being staggered;

[0028] Figure 7 For the present invention Figure 6 A schematic diagram of inserting the first handle and the second handle into the slip hanger;

[0029] Figure 8 It is an exploded view of the lower extension part and the mounting shell in the first embodiment of the present invention;

[0030] Fig. 9 For the present invention Figure 8 A top view of the mounting shell;

[0031] Fig.10 It is a schematic structural diagram of the locking mechanism and the wedge plate in the first embodiment of the present invention;

[0032] Fig.11 It is a schematic diagram of the locking block located inside the mounting shell in the first embodiment of the present invention;

[0033] Fig.12 It is a schematic diagram of the top screw locking the slip teeth after the slip hanger is moved down into position in the first embodiment of the present invention;

[0034] Fig.13 For the present invention Fig.10 A top view of

[0035] Fig.14 This is a bottom view of the lower extension portion in the first embodiment of the present invention;

[0036] Fig.15 It is a structural schematic diagram of the rotary tool of the present invention;

[0037] Fig.16 Schematic diagram of embedding a C-shaped pressing plate in the embedding groove 412 in the first embodiment of the present invention;

[0038] Fig.17 It is a schematic diagram of the position of the main limiting guide groove of the present invention;

[0039] Fig.18 This is a schematic diagram of the structure of the locking mechanism in the second embodiment of the present invention;

[0040] Fig.19 It is an exploded view of the lower extension part and the mounting shell in the second embodiment of the present invention;

[0041] Fig. 20 The locking mechanism and the mounting shell in the second embodiment of the present invention are matched Figure 1 ;

[0042] Fig.21 The locking mechanism and the mounting shell in the second embodiment of the present invention are matched Figure 2 ;

[0043] Fig. 22 This is a bottom perspective view of the lower extension portion in the second embodiment of the present invention.

[0044] In the figure, 1, oil layer casing; 21, top screw; 22, pressure cap; 3, flange shell; 31, flange body; 32, flange hole; 33, pressure cap hole; 34, pipe connection part; 35, main limit guide groove; 36, slope mouth; 37, top screw hole; 38, slope stop; 4, slip hanger; 41, slip shell; 411, handle hole 1; 412, embedded groove; 42, slip tooth; 43, slip seat; 44, support seat; 45, lower extension; 451, handle hole 2; 452, accommodating groove; 453, annular groove; 5, wedge plate; 51, bottom slope; 52, limit slide groove; 7, locking mechanism; 71, rotating cylinder; 711, spiral groove; 72, rotating Rotating gear; 73, axle; 74, sliding rod; 741, guide rod; 75, driving structure; 751, worm wheel; 752, worm; 753, transmission gear; 754, force hole; 76, force plate; 77, second spring; 78, force rod; 79, locking block; 8, through hole; 9, first handle; 10, second handle; 11, first spring; 15, mounting shell; 151, limiting protrusion; 152, rotating channel; 16, inferior arc ring; 161, tooth portion; 162, connecting rod one; 163, auxiliary ring; 164, lower protrusion; 165, connecting rod two; 100, C-shaped plate; 200, rotating tool; 300, C-shaped pressure plate. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inside", "all around" and the like indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0047] According to the following Figure 2-Figure 22 The wellhead casing head provided by the present invention is described.

[0048] Embodiment 1: This embodiment refers to Figure 2-Figure 17 .

[0049] like Figure 2 , Figure 3 As shown, an embodiment of the present invention provides a wellhead casing head, including a flange shell 3 and a slip hanger 4, wherein the flange shell 3 includes a flange body 31 and a connecting pipe portion 34, and the flange body 31 and the connecting pipe portion 34 have a hollow cavity for accommodating the slip hanger 4. A flange hole 32 is provided on the upper portion of the flange body 31 for connecting the secondary casing head. Top screw holes 37 are radially provided on the four sides of the flange body 31, and the top screw holes 37 are used to screw in the top screws 21, and a pressure cap hole 33 is provided at the outer end of the top screw hole 37 for accommodating the pressure cap 22. The top screw 21 is used to apply pressure to achieve the hanging of the slip hanger 4 on the oil layer casing 1, and the pressure cap 22 is used to further lock the position of the top screw 21.

[0050] like Figure 2-Figure 4 As shown, the above-mentioned cava hanger 4 should be a hanger with two halves coupled. Specifically, the cava hanger 4 includes a cava shell 41, a cava seat 43 located at the lower end of the cava shell 41, and a support seat 44 located at the lower end of the cava seat 43. The cava shell 41, the cava seat 43 and the support seat 44 are all composed of two semi-annular structures. Specifically, the support seat 44 and the cava seat 43 are mutually engaged, so that the support seat 44 and the cava seat 43 form an integral body and can move synchronously. A track is set on the upper surface of the cava seat 43, and the cava shell 41 can rotate on the track. When the joint seam of the cava shell 41 is aligned with the joint seam of the support seat 44, the cava hanger 4 is in a separable state (such as Figure 4 ), the separated form is as follows Figure 5As shown, when the joint seam of the slip housing 41 and the support seat 44 form a 90° angle, Figure 6 As shown, the entire slip hanger 4 is in a locked state at this time.

[0051] like Figure 4-Figure 6 An extrusion chamber is provided in the slip shell 41, and a slip tooth 42 is provided in the extrusion chamber. There are at least four groups of slip teeth 42, and the four groups of slip teeth 42 are evenly distributed in the extrusion chamber. The slip teeth 42 can move downward when subjected to downward pressure (this force is provided by the conical head of the top screw 21). The extrusion chamber can reduce the diameter of the circular structure formed by the four slip teeth 42, so that the slip teeth 42 can hold the oil layer casing 1 tightly to achieve the hanging of the oil layer casing 1.

[0052] like Figure 6 and Figure 7 A handle hole 1 411 is radially provided near the upper part of the slip housing 41. Two handle holes 1 411 are provided on each slip housing 41. The arc between the two handle holes 1 411 is equal to the arc length corresponding to the 90° angle. There are four handle holes 1 411 in total. A lower extension 45 is extended at the lower end of each support seat 44. A handle hole 2 451 is provided in the middle of each semi-annular structure constituting the lower extension 45. Four first handles 9 can be inserted into the four handle holes 1 411, and two second handles 10 can be inserted into the two handle holes 2 451. When the slip hanger 4 is not in use, the slip hanger 4 is usually in a Figure 7 Status shown.

[0053] When it is necessary to hang the slips, the two halves of the coupled slip hanger need to be separated first. During operation, the second handle 10 is used to control the support seat 44 to be unable to operate circumferentially, and the first handle 9 is used to rotate the slip housing 41 90° to make the slip housing 41 and the support seat 44 axially aligned to form a Figure 4 The state shown, then the two halves of the coupled hanger are separated radially to form Figure 5 In the state shown, the first handle 9 and the second handle 10 are separated from the slip hanger 4, and then the sitting and hanging operation can be carried out.

[0054] Combination Figure 2-Figure 4 , Fig.11 As shown, at least two outwardly radiating wedge plates 5 are installed in each lower extension 45 through the first spring 11, and the bottom surface of the wedge plate 5 is provided with a bottom slope 51, and the wedge plate 5 can be retracted into the lower extension 45 or ejected out of the lower extension 45 by the first spring 11, and a slope opening 36 is provided at the inner edge of the upper end opening of the flange shell 3, and a main limit guide groove 35 (such as Fig.17), and the main limit guide groove 35 is opposite to the position of the wedge plate 5. When it is necessary to hang, there is no need to use the C-shaped plate 100 to pad the upper surface of the flange housing 3. It is only necessary to insert the wedge plate 5 on the entire slip hanger 4 into the corresponding main limit guide groove 35 on the ramp mouth 36 (such as Figure 2 and Figure 3 The figure shows the state where the wedge plate 5 is inserted into the corresponding main limiting guide groove 35 on the ramp opening 36).

[0055] Since the wedge plate 5 is squeezed by the main limit guide groove 35 (the first spring 11 is compressed) when it is inserted into the main limit guide groove 35 on the ramp mouth 36, the entire slip hanger 4 is in an unstable state when supported above the flange housing 3. Therefore, in order to ensure that the wedge plate 5 can be kept and stably held in the main limit guide groove 35 on the ramp mouth 36, Figure 3 In the state shown, a locking mechanism 7 is also provided here, which is used to lock or unlock the position of the wedge plate 5. Figure 3 When the lower extension portion 45 is in the state shown, the position of the wedge plate 5 can be kept stable when the wedge plate 5 is stuck in the main limit guide groove 35 on the slope mouth 36, ensuring that it will not be retracted into the lower extension portion 45 by a small amount, forming a state in which the slip hanger 4 is supported on the upper end of the flange shell 3; when the locking mechanism 7 unlocks the position of the wedge plate 5, due to the elastic force of the first spring 11, the slip hanger 4 can still be supported on the upper surface of the flange shell 3, but at this time, after the blowout preventer group is used to apply downward pressure to the slip hanger 4, the main limit guide groove 35 will generate a large pressure on the wedge plate 5, so that the wedge plate 5 can be stably moved downward along the main limit guide groove 35, thereby achieving the purpose of stable downward movement of the slip hanger 4 and avoiding eccentricity of the slip hanger 4 and the oil layer casing 1 relative to the flange shell 3.

[0056] In addition, after the slip hanger 4 is supported above the flange housing 3, in fact, Figure 4 In the state shown, it is also necessary to rotate the slip housing 41 to Figure 4 The state shown is rotated into Figure 7 As shown in the state, the main limiting guide groove 35 in this embodiment can also limit the following movement of the support seat 44 below when the slip housing 41 rotates.

[0057] Preferably, a retaining slope 38 is provided on the inner wall of the connecting pipe portion 34, and a slope body adapted to the retaining slope 38 is provided on the lower surface of the supporting seat 44, so that after the slip hanger 4 moves down into the flange shell 3, the retaining slope 38 can support the slip hanger 4 and move it down into place.

[0058] like Figure 8 and Fig. 9As shown, preferably, in this embodiment, in order to facilitate the installation of the entire locking mechanism 7, a receiving groove 452 is opened in the area opposite to the wedge plate 5 on the lower extension 45, and a mounting shell 15 is fixed in the receiving groove 452. The locking mechanism 7 is arranged in the mounting shell 15, and the mounting shell 15 has a sliding chamber that enables the wedge plate 5 to slide, and the first spring 11 is located in the sliding chamber.

[0059] Combination Figure 8-Figure 11 and Fig.13 As shown, specifically, the locking mechanism 7 mentioned above includes a locking block 79, a minor arc ring 16, a driving structure 75 and a transmission structure.

[0060] The locking block 79 is located in the area near the outer edge of the sliding chamber (the outer edge here refers to the side away from the center of the lower extension 45), and the locking block 79 can move in the vertical direction, so that the locking block 79 can prevent the wedge plate 5 from retracting into the mounting shell 15 or the locking block 79 does not prevent the wedge plate 5 from retracting into the mounting shell 15. When the locking block 79 prevents the wedge plate 5 from retracting into the mounting shell 15, it is in the Figure 3 The state shown, at this time the wedge plate 5 is in the extended state; the locking block 79 does not prevent the wedge plate 5 from being retracted into the mounting shell 15. Fig.12 In the state shown, the wedge plate 5 is in a retracted state.

[0061] Preferably, the upper and lower surfaces of the wedge plate 5 are provided with limit grooves 52, and the upper and lower surfaces of the mounting shell 15 are fixed with limit protrusions 151, and the limit protrusions 151 cooperate with the limit grooves 52 to limit the limit grooves 52 from excessively extending out of the mounting shell 15. Fig.11 In the state shown, the limiting protrusion 151 reaches the endmost position of the limiting slide groove 52. At this time, the first spring 11 is in a compressed state, which can apply pressure to the wedge plate 5, but the wedge plate 5 will not escape from the sliding chamber of the mounting shell 15 to the right.

[0062] There are two inferior arc rings 16, which are distributed in the two lower extensions 45. In fact, the inferior arc rings 16 are assembled in the mounting shell 15, and are rotatably assembled on one side of the mounting shell 15 close to the center of the slip hanger 4, and a rotating channel 152 (such as Fig.11 As shown), it should also be noted that the lower extension portion 45 should also be provided with an annular groove 453 for the inferior arc ring 16 to rotate, as shown in FIG. Fig.14 shown.

[0063] The driving structure 75 is used to drive the minor arc ring 16 to rotate, and the transmission structure is used to convert the rotational force of the minor arc ring 16 into the force required for the vertical displacement of the locking block 79, so as to achieve the purpose of locking or unlocking the position of the wedge plate 5 by the locking block 79.

[0064] It should be noted that, since the arc of the minor arc ring 16 is less than 180°, it can rotate in the lower extension portion 45 on one side without reaching the other lower extension portion 45 .

[0065] Combination Fig.10 , Fig.11 and Fig.13 As shown, specifically, the transmission structure includes a slide rod 74 and a rotating gear 72; one end of the slide rod 74 is fixed on a locking block 79, and a rotating cylinder 71 is rotatably installed in a position opposite to the other end of the slide rod 74 in the mounting shell 15 through a wheel axle 73, and a spiral groove 711 adapted to the slide rod 74 is provided on the outer arc surface of the rotating cylinder 71; the rotating gear 72 is fixed on the wheel axle 73, and the outer surface of the inferior arc ring 16 is provided with a tooth portion 161 meshing with the rotating gear 72.

[0066] In this embodiment, when the minor arc ring 16 rotates, it can drive the rotating gear 72 to rotate, thereby driving the rotating cylinder 71 to rotate through the wheel shaft 73. When the rotating cylinder 71 rotates, the limiting effect of the spiral groove 711 thereon can drive the sliding rod 74 to produce a vertical displacement, thereby adjusting the position of the locking block 79, thereby achieving locking or unlocking of the wedge plate 5 by the locking block 79.

[0067] Preferably, the slide bar 74 is an L-shaped structure.

[0068] Preferably, a guide rod 741 for guiding the slide rod 74 is provided in the mounting shell 15 .

[0069] Preferably, the curvature of the spiral groove 711 along the outer circumferential surface of the rotating cylinder 71 should be set smaller, for example, the spiral groove 711 only occupies a small section of the circumference of the rotating cylinder 71, that is, it is only spiral 9°-12°; this is because the rotation angle of the minor arc ring 16 is limited, which leads to the limited rotation angle of the rotating cylinder 71. When the curvature of the spiral groove 71 is set smaller, the rotation angle of the minor arc ring 16 is smaller, and the locking block 79 can lock or unlock the wedge plate 5 when the displacement is small.

[0070] Continue to refer to Fig.10 , Fig.11 and Fig.13 As shown, the driving structure 75 mentioned above is arranged at one end of the two minor arc rings 16 close to each other, that is, the driving structure 75 is arranged in the joint area of ​​the two lower extensions 45, so that the rotation of the two minor arc rings 16 can be controlled at one time.

[0071] Specifically, the driving structure 75 includes a worm wheel 751, a worm 752 and a force application hole 754; the worm wheel 751 is fixed on two wheel shafts 73 near the end of the minor arc ring 16, the worm 752 is meshed on one side of the worm wheel 751, and a transmission gear 753 is fixed on the end of the worm 752 away from the center of the slip hanger 4 (it should be noted that the area of ​​the worm 752 assembled with the transmission gear 753 is the optical axis), and the two transmission gears 753 are meshed, and a through hole 8 is opened on the mounting shell 15 at a position opposite to the transmission gear 753 (such as Figure 5 As shown), when the two lower extensions 45 are matched, the two openings 8 can mesh with each other, so that when one of the worms 752 rotates, the other worm 752 can rotate synchronously through the action of the transmission gear 753, so that the two worm wheels 751 can rotate at the same speed, realizing the rotation of the two rotating gears 72 under the two worm wheels 751, and the two rotating gears 72 under the worm wheels 751 can drive the minor arc ring 16 to rotate through the tooth portion 161, thereby achieving the purpose of the subsequent minor arc ring 16 driving the remaining rotating cylinders 71 to rotate.

[0072] Preferably, the force hole 754 is fixed at one end of one of the worms 752 away from the center of the lower extension 45, and the inner cavity of the force hole 754 is a hexagonal groove. An operating hole is opened in the area opposite to the force hole 754 on the lower extension 45. Fig.15 The hexagonal head of the rotating tool 200 is inserted into the force application hole 754, and the rotating tool 200 is manually rotated, so that the worm 752 can be rotated.

[0073] Therefore, the wellhead casing head provided in the embodiment of the present invention can achieve locking or unlocking of the locking block 79 by rotating the rotary tool 200, thereby making the locking and unlocking of the device more convenient.

[0074] In this embodiment, when a wedge plate 5 is equipped with two upper and lower locking blocks 79, the two locking blocks 79 better limit the position of the wedge plate 5. At this time, the inferior arc ring 16 on one side should be provided with two groups, one upper group and one lower group, and the two groups are connected by a connecting rod 165. Fig.10 .

[0075] When in use: the following steps are included: 1) first assemble the flange housing 3 with the blowout preventer, and then install the slip hanger 4 after cementing. However, if the cement return height is greater than 300m, install the slip hanger 4 after the cement is completely solidified 24 hours after cementing. No couplings shall appear one meter above and two meters below the installation position of the slip hanger 4.

[0076] 2) When installing the slip hanger 4, first remove the bolts between the BOP group and the flange housing 3, and completely release the hanging weight of the oil layer casing 1, and measure and record the lowering distance of the oil layer casing 1, then lift up and lock and stabilize the BOP group. Note that the lifting height must be no less than 45 cm, and support three columns or jacks between the flange housing 3 and the BOP group to support and fix the BOP group.

[0077] 3) Clean the top surface of flange housing 3.

[0078] 4) The slip hanger 4 should be Figure 7 In the state shown in FIG. 1 , when the slip hanger 4 needs to be assembled again, the two halves of the coupled slip hanger 4 should be separated. Figure 7 In the state shown, the support seat 44 is controlled to be unable to rotate by the second handle 10, and the slip housing 41 is rotated 90° by the first handle 9, so that the slip housing 41 and the support seat 44 are axially aligned to form a Figure 4 The state shown in the figure, the two halves of the coupled slip hanger 4 are then separated radially to form Figure 5 Status shown.

[0079] 5) Place the two-piece separated slip hanger 4 on the top of the flange housing 3. Specifically, when placing it, the first handle 9 should be opposite to the top screw hole 37. At this time, the wedge plate 5 on the entire slip hanger 4 is inserted into the corresponding main limit guide groove 35 on the opposite slope opening 36. Then, by rotating the first handle 9, the slip housing 41 can be rotated 90°, and the seam of the support seat 44 is staggered with the seam of the slip housing 41 to form Figure 2 and Figure 3 In the state shown, the locking mechanism 7 is in a state of locking the wedge plate 5 outside the extended lower portion 45, so that the entire slip hanger 4 can be supported above the flange shell 3. At this time, the slip hanger 4 is outside the oil layer casing 1.

[0080] 6) Remove the first handle 9 and the second handle 10, and use the rotating tool 200 to insert into the force application hole 754, and drive one of the worms 752 to rotate. The other worm 752 can rotate synchronously through the action of the transmission gear 753, so that the two worm wheels 751 can rotate at the same speed, realizing the rotation of the two rotating gears 72 under the two worm wheels 751. The two rotating gears 72 under the worm wheels 751 can drive the minor arc ring 16 to rotate through the tooth portion 161, and the minor arc ring 16 drives the remaining rotating cylinders 71 to rotate. When the rotating cylinder 71 rotates, the limiting effect of the spiral groove 711 thereon can drive the slide bar 74 to produce a vertical displacement, so that the locking block 79 moves, and then the position of the wedge plate 5 is unlocked. At this time, the wedge plate 5 can still be supported above the flange housing 3 due to the pressure of the first spring 11. After unlocking, the operator removes the rotating tool 200, and then places the C-shaped pressing plate 300 in the embedded groove 412 on the upper surface of the slip housing 41 to form Fig.16 In the state shown, the three columns or jacks are removed and the blowout preventer group is gradually moved downward, and the gravity of the blowout preventer group is used to force the slip hanger 4 to descend into place in the flange housing 3, and the blowout preventer group is lifted to its original position, and the three columns or jacks are used again to support the blowout preventer group, and then the two C-shaped pressure plates 300 are removed.

[0081] 7) Screw in each jack screw 21 respectively, so that the jack screw 21 enters the jack screw hole 37, but the jack screw 21 does not contact the slip teeth 42, so as to prevent the jack screw 21 from locking the slip teeth 42 and causing the entire slip hanger 4 to be pulled out when the oil layer casing 1 is lifted in the next step.

[0082] 8) Lift up the oil layer casing 1 and keep it in the lifting state. The net pulling force for the oil layer casing is 50-60 tons.

[0083] 9) Tighten the four top screws 21 respectively. When the top screws 21 are screwed in, the conical head can generate pressure on the slip teeth 42. This pressure can make the slip teeth 42 gradually enter the extrusion cavity, so that the multiple slip teeth 42 form a circular shape with a reduced diameter, so that each slip tooth 42 can evenly hold the oil layer casing 1.

[0084] 10) Release the hanging weight of the oil layer casing 1 to zero, and apply the weight of the oil layer casing 1 to the slip teeth 42 to make it hold the oil layer casing 1 tightly. Note that the sliding distance of the oil layer casing 1 relative to the slip teeth 42 should not be greater than 10mm, otherwise it needs to be re-hung.

[0085] Embodiment 2: This embodiment refers to Figure 18-Figure 22 .

[0086] The difference between this embodiment and the first embodiment is that the transmission structure here includes a force-bearing rod 78, the force-bearing rod 78 is fixedly connected to the locking block 79, and the middle part of the force-bearing rod 78 is sleeved in the force-bearing plate 76, the force-bearing plate 76 is fixedly arranged in the mounting shell 15, the upper part of the force-bearing plate 76 is provided with a second spring 77, and the second spring 77 is sleeved on the outside of the force-bearing rod 78, the second spring 77 is arranged between the top of the force-bearing rod 78 and the force-bearing plate 76, when the second spring 77 is in a natural state, the locking block 79 is upwardly separated from the sliding space, and when the second spring 77 is under pressure, the locking block 79 is inserted into the sliding space; an auxiliary ring 163 is provided on the side of the force-bearing rod 78 away from the wedge plate 5, the lower surface of the auxiliary ring 163 is provided with a lower protrusion 164, and a connecting rod 162 is fixed between the minor arc ring 16 and the auxiliary ring 163.

[0087] In this embodiment, when the minor arc ring 16 rotates, the auxiliary ring 163 can be driven to rotate through the connecting rod 162. When the auxiliary ring 163 rotates, the lower protrusion 164 below it can gradually press down the force rod 78, so that the force rod 78 compresses the second spring 77 and pushes the locking block 79 downward, thereby achieving the purpose of the locking block 79 blocking the wedge plate 5 from sliding. Conversely, when the minor arc ring 16 rotates in the opposite direction, the lower protrusion 164 disengages from the force rod 78, so that the second spring 77 rebounds, and the locking block 79 no longer blocks the wedge plate 5 from sliding.

[0088] In addition, the driving structure 75 in this embodiment is actually the same as the previous embodiment. The outer surfaces of the two inferior arc rings 16 at one end close to each other are both provided with a tooth portion 161, and the outer side of the tooth portion 161 is meshed with a rotating gear 72, and the rotating gear 72 is rotatably installed in the mounting shell 15 through the wheel shaft 73; the driving structure 75 includes a worm wheel 751, a worm 752 and a force application hole 754: the worm wheel 751 is fixed on the wheel shaft 73; the worm 752 is meshed on one side of the worm wheel 751, and the worm 75 A transmission gear 753 is fixedly arranged at one end away from the center of the slip hanger 4, and the two transmission gears 753 are meshed. A through hole 8 is provided on the mounting shell 15 at a position opposite to the transmission gear 753, so that the two transmission gears 753 can mesh with each other when the two lower extensions 45 are aligned. A force application hole 754 is fixed on one of the transmission gears 753, and the inner cavity of the force application hole 754 is a hexagonal groove. An operating hole is provided on the lower extension 45 at a region opposite to the force application hole 754.

[0089] In this embodiment, Fig.15The hexagonal head of the rotating tool 200 shown is inserted into the force hole 754, and the rotating tool 200 is manually rotated, so that the worm 752 can be rotated. When one of the worms 752 rotates, the other worm 752 can rotate synchronously through the action of the transmission gear 753, so that the two worm wheels 751 can rotate at the same speed, realizing the rotation of the two rotating gears 72 under the two worm wheels 751. The two rotating gears 72 under the worm wheels 751 can drive the minor arc ring 16 to rotate through the tooth portion 161, so that the subsequent minor arc ring 16 drives the auxiliary ring 163 to rotate by driving the connecting rod 162.

[0090] like Fig. 22 Preferably, an annular groove 453 for accommodating the auxiliary ring 163 and the minor arc ring 16 is also provided on the lower extension portion 45, and a groove cavity for the connecting rod 162 to rotate is provided.

[0091] In this embodiment, when a wedge plate 5 is equipped with two upper and lower locking blocks 79, the two locking blocks 79 better limit the wedge plate 5. At this time, the single-sided inferior arc ring 16 can still only be set in one group, but the auxiliary ring 163 needs to be set in two groups, which are connected by a connecting rod 165.

[0092] The specific steps of using this embodiment differ from those of the first embodiment only in that: 6) the first handle 9 and the second handle 10 are disassembled, and the rotating tool 200 is inserted into the force application hole 754 to drive one of the worms 752 to rotate, and the other worm 752 can rotate synchronously through the action of the transmission gear 753, so that the two worm wheels 751 can rotate at the same speed, and the two rotating gears 72 under the two worm wheels 751 can rotate, and the two rotating gears 72 under the worm wheels 751 can drive the minor arc ring 16 to rotate through the tooth portion 161, so that the minor arc ring 16 can subsequently drive the auxiliary ring 163 to rotate by driving the connecting rod 162, and when the auxiliary ring 163 rotates, the lower convex portion 164 under it The second spring 77 rebounds and the locking block 79 no longer blocks the wedge plate 5 from sliding, thereby unlocking the wedge plate 5. At this time, the wedge plate 5 can still be supported on the top of the flange housing 3 due to the pressure of the first spring 11. After unlocking, the operator removes the rotary tool 200, and then places the C-shaped pressure plate 300 in the embedded groove 412 on the upper surface of the slip shell 41. At this time, the three columns or jacks are removed, and the blowout preventer group is gradually moved downward. The gravity of the blowout preventer group is used to force the slip hanger 4 to descend into place in the flange housing 3, and the anti-air jet group is lifted to its original position, and the three columns or jacks are used again to support the anti-air jet group, and then the two C-shaped pressure plates 300 are removed.

Claims

1. A wellhead casing head, characterized in that: It comprises a flange housing (3), a slip hanger (4) and a locking mechanism (7); The slip hanger (4) comprises a support seat (44) located at the bottom of the slip hanger (4), the support seat (44) comprising a circular ring structure formed by two semi-ring structures, a lower end of each support seat (44) is provided with a lower extension (45), at least two outwardly radiating wedge plates (5) are installed in each lower extension (45) via a first spring (11), and the wedge plates (5) can be retracted into the lower extension (45) or ejected out of the lower extension (45) via the first spring (11), and the bottom surface of the wedge plates (5) is provided with a bottom slope surface (51); The inner edge of the upper opening of the flange housing (3) is provided with a slope opening (36), and the inner wall of the flange housing (3) is provided with a main limit guide groove (35) extending downward from the slope opening (36), and the main limit guide groove (35) is opposite to the wedge plate (5); The locking mechanism (7) is arranged on the lower extension (45), and is used to lock or unlock the position of the wedge plate (5). The locking mechanism (7) locks the wedge plate (5) and is used to position the wedge plate (5) in the main limit guide groove (35) on the slope opening (36), so that the slip hanger (4) is supported on the upper end of the flange housing (3). When the locking mechanism (7) unlocks the wedge plate (5), the wedge plate (5) can stably move downward along the main limit guide groove (35); A receiving groove (452) is provided in an area of ​​the lower extension (45) opposite to the wedge-shaped plate (5), a mounting shell (15) is fixed in the receiving groove (452), the locking mechanism (7) is arranged in the mounting shell (15), and the mounting shell (15) has a sliding chamber capable of sliding the wedge-shaped plate (5), and the first spring (11) is located in the sliding chamber; The locking mechanism (7) comprises: A locking block (79) is included, wherein the locking block (79) is located in a region close to the outer edge of the sliding chamber, and the locking block (79) can move in a vertical direction, so that the locking block (79) can prevent the wedge plate (5) from being retracted into the mounting shell (15) or the locking block (79) does not prevent the wedge plate (5) from being retracted into the mounting shell (15); Minor arc rings (16), wherein two of the minor arc rings (16) are provided, each of which is rotatably assembled on one side of the mounting shell (15) close to the center of the slip hanger (4), and a rotating channel (152) for the minor arc ring (16) to rotate is provided in the mounting shell (15); A driving structure (75), wherein the driving structure (75) is used to drive the minor arc ring (16) to rotate; A transmission structure, the transmission structure is used to convert the rotational force of the minor arc ring (16) into a force required for the vertical displacement of the locking block (79); A slide bar (74), one end of the slide bar (74) being fixed on a locking block (79); a rotating cylinder (71) being rotatably mounted in the mounting shell (15) at a position opposite to the other end of the slide bar (74) via a wheel shaft (73); a spiral groove (711) matching the slide bar (74) being formed on an outer arc surface of the rotating cylinder (71); the rotating cylinder (71) being able to drive the slide bar (74) to generate vertical displacement when rotating; and a guide rod (741) for guiding the slide bar (74) being provided in the mounting shell (15); a rotating gear (72), the rotating gear (72) being fixedly mounted on the wheel shaft (73); the outer surface of the minor arc ring (16) being provided with a tooth portion (161) meshing with the rotating gear (72); and the minor arc ring (16) being able to drive the rotating gear (72) to rotate when rotating; The driving structure (75) is arranged at one end of the two inferior arc rings (16) close to each other; The drive structure (75) comprises: A worm wheel (751), wherein the worm wheel (751) is fixed on two wheel shafts (73) near the ends of the minor arc ring (16); A worm (752), the worm (752) meshing with one side of the worm wheel (751), and a transmission gear (753) is fixedly provided at one end of the worm (752) away from the center of the slip hanger (4), and the two transmission gears (753) are meshing with each other, and a through opening (8) is provided on the mounting shell (15) at a position opposite to the transmission gear (753), and when the two lower extensions (45) are aligned, the two transmission gears (753) can mesh with each other through the two through openings (8); A force application hole (754), the force application hole (754) being provided at one end of one of the worms (752) away from the center of the lower extension (45), and the inner cavity of the force application hole (754) being a hexagonal groove, and an operating hole being provided in a region of the lower extension (45) opposite to the force application hole (754); The upper and lower surfaces of the wedge-shaped plate (5) are both provided with limiting sliding grooves (52), and the upper and lower surfaces inside the mounting shell (15) are both fixedly provided with limiting protrusions (151), and the limiting protrusions (151) cooperate with the limiting sliding grooves (52).

2. A wellhead casing head according to claim 1, characterized in that: The transmission structure comprises a force-bearing rod (78), the force-bearing rod (78) is fixedly connected to a locking block (79), and the middle part of the force-bearing rod (78) is sleeved in a force-bearing plate (76), the force-bearing plate (76) is fixedly arranged in a mounting shell (15), a second spring (77) is arranged on the upper part of the force-bearing plate (76), and the second spring (77) is sleeved outside the force-bearing rod (78), the second spring (77) is arranged between the top of the force-bearing rod (78) and the force-bearing plate (76), when the second spring (77) is in a natural state, the locking block (79) is upwardly separated from the sliding space, and when the second spring (77) is in a compressed state, the locking block (79) is inserted into the sliding space; An auxiliary ring (163) is provided on the side of the force-bearing rod (78) away from the wedge plate (5), a lower convex portion (164) is provided on the lower surface of the auxiliary ring (163), and a connecting rod 1 (162) is fixedly provided between the inferior arc ring (16) and the auxiliary ring (163).

3. A wellhead casing head according to claim 2, characterized in that: The outer surfaces of the two minor arc rings (16) at one end close to each other are both provided with a toothed portion (161), the outer side of the toothed portion (161) is meshed with a rotating gear (72), and the rotating gear (72) is rotatably mounted in the mounting shell (15) via a wheel shaft (73); The drive structure (75) include: A worm wheel (751), wherein the worm wheel (751) is fixed on the wheel shaft (73); A worm (752), the worm (752) meshing with one side of the worm wheel (751), and a transmission gear (753) is fixedly provided at one end of the worm (752) away from the center of the slip hanger (4), and the two transmission gears (753) are meshing with each other, and a through opening (8) is provided on the mounting shell (15) at a position opposite to the transmission gear (753), and when the two lower extensions (45) are aligned, the two transmission gears (753) can mesh with each other through the two through openings (8); A force application hole (754) is fixed on one of the transmission gears (753), and the inner cavity of the force application hole (754) is a hexagonal groove. An operating hole is provided in an area of ​​the lower extension (45) opposite to the force application hole (754).

4. A wellhead casing head according to claim 3, characterized in that: The slip hanger (4) further comprises: A slip shell (41), the slip shell (41) being composed of two semi-annular structures, and having an extrusion cavity therein; a slip seat (43) being composed of two semi-annular structures is provided at the lower end of the slip shell (41); the support seat (44) is provided at the lower end of the slip seat (43); when the connecting seam of the slip shell (41) is aligned with the connecting seam of the support seat (44), the slip hanger (4) is in a state capable of being separated; The extrusion chamber is provided with slip teeth (42), and at least four groups of the slip teeth (42) are provided, and the four groups of slip teeth (42) are evenly distributed in the extrusion chamber. When the slip teeth (42) are subjected to downward pressure, they can move downward, and the extrusion chamber can reduce the diameter of the slip teeth (42), and the slip teeth (42) can hold the oil layer casing (1) tightly.

5. A wellhead casing head according to claim 4, characterized in that: The upper part of the flange shell (3) is a flange body (31), and the lower part of the flange shell (3) is a connecting pipe part (34). A retaining slope (38) is provided inside the connecting pipe part (34). The outer edge of the lower end of the support seat (44) is provided with a slope surface adapted to the retaining slope (38). After the slip hanger (4) moves downward into the flange shell (3), the retaining slope (38) can support the slip hanger (4).

6. A wellhead casing head according to claim 5, characterized in that: The four sides of the flange body (31) are provided with top screw holes (37), and a pressing cap hole (33) is provided on the side of the top screw hole (37) away from the center of the flange housing (3); A top screw (21) is provided in the top screw hole (37), and a conical structure is provided at one end of the top screw (21) close to the center of the flange housing (3); A pressing cap (22) is provided on the side of the top screw (21) away from the center of the flange housing (3), and the pressing cap (22) is located in the pressing cap hole (33).

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