An elastic casing centralizer with automatic adjustment function

Abstract

The present invention discloses an elastic casing centralizer with automatic adjustment function, which relates to the technical field related to low-carbon mining, and includes a centralizer body, wherein the outer wall of the centralizer body is fixedly connected with a plurality of groups of fixed blocks along the circumferential direction, at least two of the fixed blocks form a group, and a pull rod is slidably connected between each group of the fixed blocks, one end of the pull rod is fixedly connected with a rack, and the rack is slidably connected with the centralizer body, and the pull rod is rotatably connected with a first rotating rod symmetrically distributed along the pull rod, and a connecting rod is rotatably connected between adjacent first rotating rods, and the connecting rod is rotatably connected with a second rotating rod symmetrically distributed along the connecting rod, and the connecting rod is fixed with a main wing. The present invention drives the auxiliary wing to automatically and adaptively approach the centralizer body according to the size of the wellhead through the main wing, so as to avoid the wing directly extruding and deforming with the inner wall of the wellhead, reduce the influence of friction resistance, make it easier to lower the casing into the well, and reduce the difficulty of lowering the pipe.

Description

Technical Field

[0001] The invention relates to the technical field related to low-carbon mining, and in particular to an elastic casing centralizer with an automatic adjustment function. Background Art

[0002] The elastic casing centralizer is a tool used in the drilling and completion of oil and gas wells to ensure the casing is centered in the wellbore. This centered placement is important for improving cementing quality, preventing casing eccentricity, and optimizing fluid flow.

[0003] The elastic casing centralizer wings commonly found on the market are usually made of highly elastic synthetic rubber, metal shrapnel or similar elastic materials. They can adapt to wellbore changes within a certain range, and maintain good elasticity in the high temperature and high pressure environment underground, forming support between the outer diameter of the casing and the well wall, and providing a stable centering effect. However, when encountering a well section with a smaller diameter, the wings relying on their own elastic material will be directly squeezed against the well wall, causing deformation or even damage of the wings, increasing maintenance and replacement costs, and during the pipe lowering process, the friction resistance between the wings and the well wall will be large, increasing the difficulty of pipe lowering, which may cause casing jamming or slow down the pipe lowering speed, increasing operation time and cost.

[0004] Based on this, the present invention proposes an elastic casing centralizer with automatic adjustment function. Summary of the invention

[0005] In order to overcome the disadvantages of deformation of the fins and increased friction resistance caused by direct hard extrusion of the fins against the well wall, the present invention provides an elastic casing centralizer with an automatic adjustment function.

[0006] The cam is connected to the outer wall of the main body of the machine according to claim 1, wherein the first and second ends of the cam are connected to the upper and lower ends of the cam, and the cam is connected to the lower wall of the main body of the machine according to the present invention.

[0007] Furthermore, the pushing assembly includes a third rotating rod corresponding to the blocking block, the third rotating rod is rotatably connected to the stabilizer body, a second spring is fixed between the third rotating rod and the stabilizer body, and the third rotating rod is fixed with a cam, and the cam squeezes the adjacent blocking block to slide toward the side close to the adjacent rack through the convex surface.

[0008] Furthermore, a plurality of fourth rotating rods are included, wherein the fourth rotating rods are rotatably connected between adjacent pulling rods and connecting rods, and the fourth rotating rods are located between adjacent first rotating rods.

[0009] Furthermore, a side of the centralizer body close to the third rotating rod is provided with circumferentially distributed bolt holes, and the bolt holes are used for installing bolts.

[0010] Furthermore, a limiting ring for limiting the position of the bolt is included, and the limiting ring is sleeved on a side of the centralizer body close to the third rotating rod.

[0011] Furthermore, it also includes circumferentially distributed limit rods, which are rotatably connected to the stabilizer body, and the limit ring is provided with a slot corresponding to the limit rod, and the limit rod is rotatably inserted into the corresponding slot to lock the limit ring.

[0012] Furthermore, it also includes a guide ring corresponding to the limit rod, the guide ring is fixedly connected to the adjacent third rotating rod, and when the third rotating rod drives the guide ring to rotate, the guide ring pushes the limit rod to rotate.

[0013] Furthermore, it also includes a plurality of rollers, which are rotatably connected to a side of the main wing close to the wedge surface.

[0014] The beneficial effects of the present invention are as follows: the present invention uses the main wing to drive the auxiliary wing to automatically and adaptively approach the stabilizer body according to the size of the wellhead, thereby avoiding the wing to be directly squeezed and deformed with the inner wall of the wellhead, reducing the influence of friction resistance, making it easier to lower the casing into the well and reducing the difficulty of lowering the casing.

[0015] The present invention squeezes the third rotating rod by the inner wall of the wellhead so that the convex surface of the cam squeezes the block to slide to clamp the adjacent rack, thereby locking the first rotating rod, the second rotating rod, the connecting rod and the main wing to ensure the stability after adaptive adjustment and eliminate the influence of the casing's own gravity.

[0016] The present invention adds two fourth rotating rods between the two first rotating rods, so that the connecting rod can more easily push the pull rod to slide leftward, and at the same time improves the stress stability of the main wing, avoiding the main wing from being sunken due to the lack of stress points in the middle.

[0017] The present invention installs bolts at the positions of bolt holes to fix the centralizer body on the casing, and by sleeve-fitting a limit ring on the left end of the centralizer body, the limit rod is rotated by the third rotating rod to lock the limit ring, so as to reinforce the bolts and prevent the bolts from loosening and ejecting upwards.

[0018] The present invention can make the main wing easier to enter the well and reduce friction by arranging a roller on the right outer side of the main wing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0020] Figure 2 It is a three-dimensional structural schematic diagram of components such as the rack, main wing and aileron of the present invention.

[0021] Figure 3 It is a three-dimensional structural schematic diagram of the connecting rod, main wing sheet, aileron sheet and other components of the present invention.

[0022] Figure 4 It is a schematic diagram of the three-dimensional structure of the rack, the clamping block, the first spring and other components of the present invention.

[0023] Figure 5 It is a three-dimensional structural schematic diagram of the third rotating rod, the second spring, the cam and other components of the present invention.

[0024] Figure 6 It is a three-dimensional structural schematic diagram of the clamping block, the first spring, the third rotating rod and other components of the present invention.

[0025] Figure 7 It is a schematic diagram of the three-dimensional structure of the connecting rod, the main wing and the fourth rotating rod of the present invention.

[0026] Figure 8 It is a schematic diagram of the three-dimensional structure of the limit rod, limit ring, guide ring and other components of the present invention.

[0027] Fig. 9 It is a three-dimensional structural schematic diagram of the centralizer body, the limit ring, the guide ring and other components of the present invention.

[0028] Fig.10 It is a schematic diagram of the three-dimensional structure of the third rotating rod, the limiting rod and the guide ring of the present invention.

[0029] Fig.11 It is a three-dimensional structural schematic diagram of the centralizer body and the limit ring and other components of the present invention.

[0030] The markings of the components in the accompanying drawings are as follows: 101: stabilizer body, 102: fixing block, 103: pull rod, 104: rack, 105: first rotating rod, 1051: second rotating rod, 106: connecting rod, 107: main wing, 108: aileron, 109: block, 110: first spring, 201: third rotating rod, 202: second spring, 203: cam, 301: fourth rotating rod, 401: limiting rod, 402: limiting ring, 403: guide ring, 404: bolt hole, 501: roller. DETAILED DESCRIPTION

[0031] 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.

[0032] Embodiment 1: An elastic casing centralizer with automatic adjustment function, such as Figure 1-Figure 4 As shown, it includes a centralizer body 101, and the outer wall of the centralizer body 101 is fixedly connected with a plurality of groups of fixed blocks 102 along the circumferential direction, wherein two fixed blocks 102 form a group, and a pull rod 103 is slidably connected between each group of fixed blocks 102 along the left and right directions, and a rack 104 is fixedly connected to the left end of the pull rod 103, and the rack 104 is slidably connected to the centralizer body 101, and the pull rod 103 is rotatably connected to first rotating rods 105 symmetrically distributed along the left and right sides of the pull rod 103, and connecting rods 106 are rotatably connected between adjacent first rotating rods 105, and the connecting rods 106 are rotatably connected to the connecting rods 106 along the left and right directions. The connecting rod 106 is symmetrically distributed with a second rotating rod 1051, and the second rotating rod 1051 is rotatably connected to the outer wall of the centralizer body 101. The wing is divided into a main wing 107 and an aile wing 108. The main wing 107 is fixedly connected to the connecting rod 106. The right side of the main wing 107 is set as a wedge surface. The aile wing 108 is fixedly connected to the middle of the main wing 107. The aile wing 108 is made of high elastic material. The centralizer body 101 is slidably connected with a block 109 corresponding to the rack 104, and a first spring 110 is fixedly connected between the block 109 and the centralizer body 101.

[0033] like Figure 5 and Figure 6 As shown, it also includes a third rotating rod 201 corresponding to the block 109, the third rotating rod 201 is rotatably connected to the stabilizer body 101, a second spring 202 is fixed between the third rotating rod 201 and the stabilizer body 101, and a cam 203 is fixed on the third rotating rod 201. The cam 203 squeezes the adjacent block 109 through the convex surface to slide toward the side close to the adjacent rack 104.

[0034] First, the centralizer body 101 is put on the casing, and a centralizer is usually installed at a certain distance. Then, the casing section is gradually hoisted and lowered through the winch system of the drilling rig. As the casing is lowered into the well, the right side of the main wing 107 will first contact the wellhead. Under the squeezing effect of the inner wall of the wellhead, the main wing 107 drives the connecting rod 106 to move to the side close to the centralizer body 101, thereby driving the second rotating rod 1051 to swing to the left, so that the connecting rod 106 and the main wing 107 will also move to the left, so that the connecting rod 106 pushes the pull rod 103 to move to the left through the first rotating rod 105. In this way, the main wing 107 will drive the auxiliary wing 108 to automatically and adaptively approach the centralizer body 101 according to the size of the wellhead, avoiding the wing directly being hard squeezed and deformed with the inner wall of the wellhead, reducing the influence of friction resistance, making it easier to lower the casing into the well, and reducing the difficulty of lowering the pipe.

[0035] When the casing reaches the predetermined position (usually the designed cementing depth), the lifting and lowering force of the casing is removed. At this time, the casing is completely in the wellbore. Due to the complex terrain in the wellbore, the casing may be in a relatively flat section. Therefore, the casing centralizer may be affected by the weight of the casing itself, causing the first rotating rod 105 and the second rotating rod 1051 on the lower side to swing further, and the main wing 107 on the lower side is further close to the centralizer body 101, thereby causing the position of the casing in the wellbore to be lowered. In order to eliminate the above-mentioned influence, the specific operation is as follows: During the lowering process, the pull rod 103 will drive the rack 104 to move to the left. When the main wing 107 is completely in the wellbore, the pull rod 103 will move the rack 104 to the left. 3 and the rack 104 will stop moving to the left. Later, when the third rotating rod 201 moves to the right with the centralizer body 101 to contact the inner wall of the wellhead, the third rotating rod 201 is squeezed by the inner wall of the wellhead and rotates downward to contact the outer wall of the centralizer body 101. The second spring 202 is stretched, and the third rotating rod 201 drives the cam 203 to rotate. The convex surface of the cam 203 squeezes the block 109 to slide and clamp the adjacent rack 104. The first spring 110 is compressed, thereby locking the first rotating rod 105, the second rotating rod 1051, the connecting rod 106 and the main wing 107 to ensure the stability after adaptive adjustment and eliminate the influence of the casing's own gravity.

[0036] In this way, the elastic casing centralizer can position the casing in the wellbore. The elastic characteristics of the fins enable them to provide stable support force to ensure the center position of the casing in the wellbore. When cementing, the centered casing can ensure that the cement slurry is evenly distributed between the casing and the well wall, thereby improving the cementing quality.

[0037] like Figure 7 As shown, a plurality of fourth rotating rods 301 are further included, and every two fourth rotating rods 301 are rotatably connected between adjacent pull rods 103 and connecting rods 106 , and the fourth rotating rods 301 are located between adjacent first rotating rods 105 .

[0038] By adding two fourth rotating rods 301 between the two first rotating rods 105, the connecting rod 106 can more easily push the pull rod 103 to slide leftward, and at the same time improve the stress stability of the main wing 107, avoiding the main wing 107 from being sunken due to the lack of stress points in the middle.

[0039] like Figure 1 As shown, a plurality of rollers 501 are also included, and the rollers 501 are rotatably connected to one side of the main wing 107 close to the wedge surface.

[0040] By arranging a roller 501 on the right outer side surface of the main wing 107, the main wing 107 can be made to enter the well more easily and reduce friction.

[0041] Embodiment 2: Based on embodiment 1, Figure 8-Figure 11 As shown, the limiting rod 401 is also distributed in the circumferential direction. The limiting rod 401 is composed of a rotating rod and a limiting buckle. The rotating rod of the limiting rod 401 is rotatably connected to the main body 101 of the centralizer. The limiting buckle of the limiting rod 401 is fixed to the left end of the rotating rod of the limiting rod 401. The left side of the centralizer main body 101 is sleeved with a limiting ring 402. The limiting ring 402 is used for bolts to limit. The limiting ring 402 is provided with a slot corresponding to the limiting rod 401. The rotation of the limiting rod 401 can drive the limiting rod 401 to rotate. The positioning buckle is inserted into the corresponding slot to lock the limit ring 402. A guide ring 403 corresponding to the limit rod 401 is fixedly connected to the side of the third rotating rod 201 close to the adjacent limit rod 401. The guide ring 403 is bent to one side so that when the third rotating rod 201 drives the guide ring 403 to rotate, the guide ring 403 pushes the adjacent limit rod 401 to rotate. The left side of the centralizer body 101 is provided with circumferentially distributed bolt holes 404, which are used to install bolts.

[0042] During the installation of the centralizer, it is necessary to install bolts at the position of the bolt holes 404 to fix the centralizer body 101 on the casing. In order to reinforce the bolts and prevent them from loosening and being pushed out upward, it is necessary to put a limit ring 402 on the left end of the centralizer body 101. In order to further reinforce the limit ring 402, the specific operation is as follows: When the third rotating rod 201 rotates, it drives the guide ring 403 to rotate. Under the guiding action of the guide ring 403 bending to one side, the guide ring 403 pushes the limit buckle of the limit rod 401 into the corresponding groove of the limit ring 402, thereby locking the limit ring 402.

[0043] The above is a detailed introduction to the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An elastic casing centralizer with automatic adjustment function, comprising a centralizer body (101), characterized in that: The outer wall of the centralizer body (101) is fixedly connected with a plurality of groups of fixed blocks (102) along the circumferential direction, at least two of the fixed blocks (102) form a group, a pull rod (103) is slidably connected between each group of the fixed blocks (102), one end of the pull rod (103) is fixedly connected with a rack (104), the rack (104) is slidably connected to the centralizer body (101), the pull rod (103) is rotatably connected with a first rotating rod (105) symmetrically distributed along the pull rod (103), adjacent first rotating rods (105) are rotatably connected with connecting rods (106), and the connecting rods (106) are rotatably connected with second rotating rods (105) symmetrically distributed along the connecting rod (106). 051), the second rotating rod (1051) is rotatably connected to the centralizer body (101), the connecting rod (106) is fixedly connected with a main wing (107), the side of the main wing (107) away from the rack (104) is set as a wedge-shaped surface, the middle of the main wing (107) is fixedly connected with an auxiliary wing (108), the centralizer body (101) is slidably connected with a clamping block (109) corresponding to the rack (104), a first spring (110) is fixedly connected between the clamping block (109) and the centralizer body (101), and the centralizer body (101) is provided with a pushing component for pushing the clamping block (109) to clamp the adjacent rack (104); The pushing assembly comprises a third rotating rod (201) corresponding to the clamping block (109), the third rotating rod (201) being rotatably connected to the centralizer body (101), a second spring (202) being fixedly connected between the third rotating rod (201) and the centralizer body (101), and a cam (203) being fixedly connected to the third rotating rod (201), the cam (203) slidingly pressing the adjacent clamping block (109) to slide toward a side close to the adjacent rack (104) through a convex surface; It also includes a plurality of fourth rotating rods (301), wherein the fourth rotating rods (301) are rotatably connected between adjacent pull rods (103) and connecting rods (106), and the fourth rotating rods (301) are located between adjacent first rotating rods (105); The centralizer body (101) is placed on the casing. As the casing is lowered into the well, the right side of the main wing (107) will first contact the wellhead. Under the squeezing effect of the inner wall of the wellhead, the main wing (107) drives the connecting rod (106) to move toward the side close to the centralizer body (101), thereby driving the second rotating rod (1051) to swing to the left, so that the connecting rod (106) and the main wing (107) will also move to the left, so that the connecting rod (106) pushes the pull rod (103) to move to the left through the first rotating rod (105). In this way, the main wing (107) will drive the auxiliary wing (108) to automatically and adaptively approach the centralizer body (101) according to the size of the wellhead, so as to avoid the wing being directly squeezed and deformed by the inner wall of the wellhead; During the process of lowering the pipe, the pull rod (103) drives the rack (104) to move to the left. When the main wing (107) completely enters the wellbore, the pull rod (103) and the rack (104) stop moving to the left. Thereafter, when the third rotating rod (201) moves to the right together with the centralizer body (101) until it contacts the inner wall of the wellhead, the third rotating rod (201) is squeezed by the inner wall of the wellhead and rotates downward until it contacts the outer wall of the centralizer body (101). The second spring (202) is stretched, and the third rotating rod (201) drives the cam (203) to rotate. The convex surface of the cam (203) squeezes the block (109) to slide and clamp the adjacent rack (104). The first spring (110) is compressed, thereby locking the first rotating rod (105), the second rotating rod (1051), the connecting rod (106) and the main wing (107).

2. The elastic casing centralizer with automatic adjustment function according to claim 1 is characterized in that: Bolt holes (404) distributed circumferentially are provided on a side of the centralizer body (101) close to the third rotating rod (201), and the bolt holes (404) are used for installing bolts.

3. The elastic casing centralizer with automatic adjustment function according to claim 2 is characterized in that: It also includes a limiting ring (402) for limiting the position of the bolts, and the limiting ring (402) is sleeved on a side of the centralizer body (101) close to the third rotating rod (201).

4. The elastic casing centralizer with automatic adjustment function according to claim 3 is characterized in that: It also includes circumferentially distributed limiting rods (401), the limiting rods (401) being rotatably connected to the centralizer body (101), the limiting ring (402) being provided with a slot corresponding to the limiting rod (401), the limiting rod (401) being rotatably engaged in the corresponding slot to lock the limiting ring (402).

5. The elastic casing centralizer with automatic adjustment function according to claim 4 is characterized in that: It also includes a guide ring (403) corresponding to the limiting rod (401), the guide ring (403) being fixedly connected to the adjacent third rotating rod (201), and when the third rotating rod (201) drives the guide ring (403) to rotate, the guide ring (403) pushes the limiting rod (401) to rotate.

6. The elastic casing centralizer with automatic adjustment function according to claim 5 is characterized in that: It also includes a plurality of rollers (501), wherein the rollers (501) are rotatably connected to a side of the main wing (107) close to the wedge surface.

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