A cementing bow casing centralizer

Abstract

The invention discloses a cementing bow-shaped casing centralizer, relates to the field of casing centralizers, and solves the problem that the outer wall structure of the existing cementing bow-shaped casing centralizer is fixed and it is difficult to flexibly switch the outer wall shape according to the inclination of the well. The invention comprises a fixing pipe, multiple groups of metal sheets, a fixing mechanism, an adjusting mechanism and a limiting mechanism. The upper and lower ends of the fixing pipe are fixedly connected with casings. The fixing mechanism comprises a mounting ring and a rotating disk. The adjusting mechanism comprises an adjusting ring and a clamping block. A limiting groove is provided in the casing. The cementing bow-shaped casing centralizer is convenient for connecting the middle part of the metal sheet with the rotating disk, and connecting and fixing the two ends of the metal sheet with the mounting ring. When the adjusting ring is rotated, the plug-in sliding state of the clamping block and the limiting groove is released, and the mounting ring is driven to rotate, so as to change the positions of the two ends of the metal sheet, adjust the overall inclination angle of the metal sheet, and limit the relative position between the adjusting ring and the casing, so as to realize the adjustment and switching function of the outer wall structure of the casing centralizer.

Description

Technical Field

[0001] The invention relates to the technical field of casing centralizers, in particular to a cementing bow-shaped casing centralizer. Background Art

[0002] With the rapid development of oil and gas development technology, the utilization of oil and gas in social life has been well guaranteed. After the drilling of oil and gas wells is completed, casing needs to be lowered for cementing operations. The casing centralizer is used to be installed on the outside of the casing, and its function is to straighten the casing. In the process of cementing and cementing of oil and gas wells, it is common practice to install a casing centralizer on the casing string at intervals, so that the center of the casing and the center of the wellbore are basically consistent, which can improve the displacement efficiency of the cement slurry in the wellbore annulus, ensure a uniform cement ring between the casing and the wellbore, prevent cement slurry from channeling, and prevent the casing from being stuck due to the pressure difference.

[0003] There are generally two types of existing cementing casing straighteners. One is a straight strip-shaped outer wall straightener, which is widely used in casing construction operations in vertical wells or high-angle wells, and has the characteristics of small starting force and large reset force. The other is a straightener with a spiral outer wall, which is used to center the casing during the completion construction of high-angle wells and horizontal wells, and can effectively reduce the friction resistance when lowering the casing. In addition, the right-handed spiral groove also has a self-cleaning effect, which can remove mud cake from the well wall and improve the efficiency of cement slurry displacement. The outer wall structure of the existing straightener is relatively fixed, and it is difficult to flexibly switch the outer wall shape according to the inclination of the well, and the scope of application is relatively small. To this end, the present application proposes a cementing bow casing straightener. Summary of the invention

[0004] The object of the present invention is to provide a cementing bow casing centralizer which can flexibly switch the outer wall shape according to the inclination of the well, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a cementing bow casing centralizer, comprising a fixed tube, multiple groups of metal sheets, a fixing mechanism, an adjusting mechanism and a limiting mechanism, the cross-section of the metal sheet is bow-shaped, the upper and lower ends of the fixed tube are fixedly connected to the casing, the fixing mechanism comprises a mounting ring installed on the casing, the outer wall of the fixed tube is evenly rotatably connected to multiple groups of rotating disks, the fixing mechanism is used to connect the middle part of the metal sheet with the rotating disk, and to connect and fix the two ends of the metal sheet with the mounting ring, the adjusting mechanism comprises an adjusting ring movably sleeved with the inner wall of the casing, multiple groups of limiting grooves are provided in the casing, The adjusting ring is provided with a plurality of groups of clamping blocks which can be slidably connected with the limiting groove in a vertical direction. The adjusting mechanism is used to release the plug-in sliding state between the clamping blocks and the limiting groove when the adjusting ring is rotated, and drive the mounting ring to rotate, thereby changing the positions of the two ends of the metal sheet and adjusting the overall inclination angle of the metal sheet. The limiting mechanism includes a plurality of groups of limit blocks installed on the adjusting ring, and the limit blocks can be plugged into the limit groove. The limiting mechanism is used to perform preliminary limit and fixation on the relative position between the adjusting ring and the casing after adjusting the inclination angle of the metal sheet, so as to facilitate flexible switching of the outer wall shape according to the inclination requirements of the well.

[0006] Preferably, the adjusting mechanism also includes a first spring fixedly mounted on one side of the clamping block, a plurality of sliding grooves are evenly formed on the outer wall of the adjusting ring, the clamping block is slidably connected to the inner wall of the sliding groove, one end of the first spring is fixedly connected to the sliding groove, the adjusting ring is provided with a rotating member for controlling the rotation state of the adjusting ring, and the sleeve is provided with a reset member for driving the adjusting ring to reset, so as to release the plug-in sliding state of the clamping block and the limiting groove when rotating the adjusting ring, and drive the mounting ring to rotate, thereby changing the positions of the two ends of the metal sheet and adjusting the overall inclination angle of the metal sheet.

[0007] Preferably, the rotating part includes a driving ring rotatably connected to one end of the adjusting ring, a plurality of arc grooves are provided on the driving ring, a driving shaft which can be slidably connected to the inner wall of the arc groove is fixedly connected to the clamping block, a driving tube is coaxially fixedly connected to the driving ring, and the inner wall of the mounting ring is fixedly connected to the outer wall of the driving tube, so as to facilitate the control of the rotation state of the adjusting ring.

[0008] Preferably, the reset member includes a sliding ring installed in the sleeve, a guide groove is provided in the sleeve, and the side of the sliding ring is provided with multiple groups of guide blocks slidably connected to the guide groove. The outer wall of the sliding ring is fixedly connected to a clockwork spring fixedly connected to the adjustment ring, so as to drive the adjustment ring to reset.

[0009] Preferably, the limiting mechanism also includes a tension spring fixedly installed on one side of the limiting block, a plurality of groups of air-filling grooves are evenly arranged on the outer wall of the adjusting ring, the limiting block is slidably connected to the air-filling grooves, one end of the tension spring is fixedly connected to the air-filling grooves, a plurality of groups of first pipes for connecting the air-filling grooves and the sleeve are arranged at the bottom of the adjusting ring, and a control component for controlling the air pressure state in the air-filling grooves is provided on the fixed pipe, so as to facilitate the preliminary limiting and fixing of the relative position between the adjusting ring and the sleeve.

[0010] Preferably, the fixing mechanism also includes a threaded tube threadedly connected to the inner wall of the rotating disk, the threaded tube passes through the middle part of the metal sheet and is rotatably connected to the metal sheet, the mounting ring is provided with multiple groups of plug-in grooves that can be plugged into any end of the metal sheet, the mounting ring is threadedly connected to multiple groups of nuts, the nuts pass through the metal sheet and are rotatably connected to the metal sheet, so as to facilitate connecting the middle part of the metal sheet to the rotating disk and connecting and fixing the two ends of the metal sheet to the mounting ring.

[0011] Preferably, the control member includes a driving rod slidably connected to the inner wall of the threaded tube, one end of the driving rod is fixedly connected to a second spring fixedly connected to the threaded tube, and the fixed tube is provided with a second pipe for connecting the threaded tube and the sleeve, so as to facilitate the control of the air pressure state in the inflation tank.

[0012] Preferably, a plurality of sets of sleeve blocks are fixedly connected to the metal sheet, and balls are rollingly connected inside the sleeve blocks to reduce friction with the well wall.

[0013] Preferably, a stopper is fixedly connected to the side of the rotating disk, and a plurality of control grooves are provided on the side of the fixed tube to facilitate limiting the rotation angle of the rotating disk and prevent the rotating disk from rotating continuously when the threaded tube rotates.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The present invention solves the problem that the outer wall structure of the existing cementing bow-shaped casing centralizer is fixed and it is difficult to flexibly switch the outer wall shape according to the inclination of the well. By arranging a fixing mechanism, an adjusting mechanism and a limiting mechanism, it is convenient to connect the middle part of the metal sheet with the rotating disk through the fixing mechanism, and to connect and fix the two ends of the metal sheet with the mounting ring. When the adjusting ring is rotated, the adjusting mechanism releases the plug-in sliding state between the clamping block and the limiting groove, and drives the mounting ring to rotate, thereby changing the positions of the two ends of the metal sheet, adjusting the overall inclination angle of the metal sheet, and realizing the adjustment and switching function of the outer wall structure of the casing centralizer. The relative position between the adjusting ring and the casing is preliminarily limited and fixed by the limiting mechanism. The device has a compact structure, can realize the function switching of the casing centralizer without installing a motor drive, can be widely applied to oil and gas wells with different inclinations, has low production and use costs, is stable and flexible in structure, and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0017] Figure 2 It is an exploded view of the local structure of the fixing mechanism of the present invention;

[0018] Figure 3 It is a schematic diagram of the structure of the regulating mechanism of the present invention;

[0019] Figure 4 for Figure 3 A magnified image of area A;

[0020] Figure 5 It is a schematic diagram of the local structure of the limiting mechanism of the present invention;

[0021] Figure 6 for Figure 5 Enlarged view of area B;

[0022] Figure 7 It is a schematic diagram of the structure of the reset member of the present invention;

[0023] Figure 8 for Figure 7 Enlarged view of area C in the middle;

[0024] Fig. 9 It is a schematic diagram of the structure of the rotating part of the present invention;

[0025] Fig.10 It is a partial structural sectional view of the regulating mechanism of the present invention;

[0026] Fig.11 for Fig.10 Enlarged view of area D in the middle.

[0027] In the figure: 1-fixed tube; 2-metal sheet; 3-sleeve; 4-fixed mechanism; 5-mounting ring; 6-rotating disk; 7-adjusting mechanism; 8-adjusting ring; 9-limiting groove; 10-clamping block; 11-limiting mechanism; 12-limiting block; 13-first spring; 14-sliding groove; 15-rotating member; 16-resetting member; 17-driving ring; 18-arc groove; 19-driving shaft; 20-driving tube; 21-sliding ring; 22-guide groove; 23-guide block; 24-spring spring; 25-tension spring; 26-inflating groove; 27-first pipeline; 28-control member; 29-threaded tube; 30-plug-in groove; 31-nut; 32-driving rod; 33-second spring; 34-second pipeline; 35-sleeve block; 36-ball; 37-stopper; 38-control groove. DETAILED DESCRIPTION

[0028] 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. Example 1

[0029] See also Figure 1-Figure 11 The cementing bow casing centralizer shown in the figure includes a fixed tube 1, multiple groups of metal sheets 2, a fixing mechanism 4, an adjusting mechanism 7 and a limiting mechanism 11. The cross section of the metal sheet 2 is arched. The upper and lower ends of the fixed tube 1 are fixedly connected to the casing 3. The fixing mechanism 4 includes a mounting ring 5 installed on the casing 3. The outer wall of the fixed tube 1 is evenly rotated and connected to multiple groups of rotating disks 6. The fixing mechanism 4 is used to connect the middle part of the metal sheet 2 with the rotating disk 6, and to connect and fix the two ends of the metal sheet 2 with the mounting ring 5. The adjusting mechanism 7 includes an adjusting ring 8 movably sleeved with the inner wall of the casing 3. The casing 3 is provided with multiple groups of The limiting groove 9 and the adjusting ring 8 are provided with a plurality of clamping blocks 10 which can be slidably connected with the limiting groove 9 in the vertical direction. The adjusting mechanism 7 is used to release the plug-in sliding state of the clamping block 10 and the limiting groove 9 when the adjusting ring 8 is rotated, and drive the mounting ring 5 to rotate, change the positions of the two ends of the metal sheet 2, and adjust the overall inclination angle of the metal sheet 2. The limiting mechanism 11 includes a plurality of limiting blocks 12 installed on the adjusting ring 8, and the limiting blocks 12 can be plugged with the limiting groove 9. The limiting mechanism 11 is used to preliminarily limit and fix the relative position between the adjusting ring 8 and the sleeve 3 after adjusting the inclination angle of the metal sheet 2.

[0030] See also Figure 2-Figure 11The adjusting mechanism 7 shown in the figure also includes a first spring 13 fixedly mounted on one side of the clamping block 10, a plurality of sliding grooves 14 are evenly arranged on the outer wall of the adjusting ring 8, the clamping block 10 is slidably connected to the inner wall of the sliding groove 14, one end of the first spring 13 is fixedly connected to the sliding groove 14, a rotating member 15 for controlling the rotation state of the adjusting ring 8 is provided on the adjusting ring 8, and a reset member 16 for driving the adjusting ring 8 to reset is provided in the sleeve 3.

[0031] See also Figure 2-Figure 11 The rotating member 15 shown in the figure includes a driving ring 17 rotatably connected to one end of the adjusting ring 8, a plurality of arc grooves 18 are provided on the driving ring 17, a driving shaft 19 which can be slidably connected to the inner wall of the arc groove 18 is fixedly connected to the clamping block 10, a driving tube 20 is coaxially fixedly connected to the driving ring 17, the inner wall of the mounting ring 5 is fixedly connected to the outer wall of the driving tube 20, the reset member 16 includes a sliding ring 21 installed in the sleeve 3, a guide groove 22 is provided in the sleeve 3, a plurality of guide blocks 23 which are slidably connected to the guide groove 22 are provided on the side of the sliding ring 21, and a clockwork spring 24 which is fixedly connected to the adjusting ring 8 is fixedly connected to the outer wall of the sliding ring 21.

[0032] In this embodiment, the middle part of the metal sheet 2 is connected to the rotating disk 6 by the fixing mechanism 4, and the two ends of the metal sheet 2 are connected and fixed to the mounting ring 5. In the normal state, due to the restoring force of the metal sheet 2 itself, the metal sheet 2 is in a vertical state as a whole. At this time, the casing 3 straightener is suitable for the construction of casing 3 in vertical wells or wells with a high inclination. During the process that the outer wall of the metal sheet 2 contacts the well wall, the clamping block 10 can slide in the limiting groove 9, so that the two ends of the metal sheet 2 can be squeezed and drive the adjusting rings 8 at both ends to slide and retract inside the casing 3 for buffering. When the inclination angle of the metal sheet 2 needs to be adjusted, the upper and lower drive tubes 20 are rotated in opposite directions, the upper drive tube 20 rotates counterclockwise, and the lower drive tube 20 rotates clockwise. The drive tube 20 drives the mounting ring 5 to rotate, so that the two ends of the metal sheet 2 rotate in different directions, and the middle part of the metal sheet 2 drives the rotating disk 6 to rotate, so that the metal sheet 2 is tilted as a whole.

[0033] It is worth noting that when the driving tube 20 rotates, the driving ring 17 will be driven to rotate first. The arc groove 18 on the driving ring 17 drives the driving shaft 19 and the clamping block 10 to slide in the sliding groove 14, compressing the first spring 13, and gradually releasing the plug-in state between the clamping block 10 and the limiting groove 9. After that, the adjusting ring 8 can be driven to rotate. When the adjusting ring 8 rotates, the clockwork spring 24 is compressed. After that, after the adjusting ring 8 is rotated to the required angle, the limiting block 12 is controlled by the limiting mechanism 11 to pop out and plug into the limiting groove 9, so that the adjusting ring 8 can be initially limited. At this time, the driving tube 20 is released, and the first spring 13 pops out the clamping block 10 and plugs into the limiting groove 9 for limiting. The driving shaft 19 slides back and forth in the arc groove 18 to reset. After the driving tube 20 rotates in the opposite direction for a certain angle, the limit is completed, and the outer wall state of the casing 3 centralizer can be changed. At this time, it is suitable for the completion construction of high-angle wells and horizontal wells.

[0034] It should be noted that: when the metal sheet 2 needs to be reset to a vertical state, the driving tube 20 is rotated to release the connection between the clamping block 10 and the limiting groove 9. At this time, the clockwork spring 24 rebounds, and the driving tube 20 is slowly rotated in the opposite direction, and the adjusting ring 8 can be pulled by the clockwork spring 24 to rotate in the opposite direction to reset. After the reset is completed, the driving tube 20 is released, and the first spring 13 pops out the clamping block 10 to complete the fixation. Since the metal sheet 2 has a certain elasticity, it can be twisted and rotated at a moving angle. When the adjusting ring 8 slides in the casing 3, it can drive the clockwork spring 24 to rise and fall synchronously, and the rebound buffer of the metal sheet 2 is not affected while completing the reset. The device has a compact structure and can realize the function switching of the casing 3 straightener without installing a motor drive. It can be widely used in oil and gas wells with different inclinations. The production and use costs are low, the structure is stable and flexible, and the operation is convenient. Example 2

[0035] See also Figure 1-Figure 6 This embodiment further illustrates the embodiment 1. The fixing mechanism 4 shown in the figure also includes a threaded tube 29 threadedly connected to the inner wall of the rotating disk 6. The threaded tube 29 passes through the middle of the metal sheet 2 and is rotatably connected to the metal sheet 2. The mounting ring 5 is provided with multiple groups of plug-in grooves 30 that can be plugged into any end of the metal sheet 2. The mounting ring 5 is threadedly connected to multiple groups of nuts 31. The nuts 31 pass through the metal sheet 2 and are rotatably connected to the metal sheet 2.

[0036] See also Figure 1-Figure 4 The metal sheet 2 shown in the figure is fixedly connected with multiple sets of socket blocks 35, and balls 36 are rollingly connected inside the socket blocks 35. A stopper 37 is fixedly connected to the side of the rotating disk 6, and multiple sets of control grooves 38 are opened on the side of the fixed tube 1.

[0037] In this embodiment, the threaded tube 29 is passed through the middle of the metal sheet 2 and is coaxially threadedly connected to the rotating disk 6. The threaded tube 29 is rotated in the counterclockwise direction so that the stopper 37 on the rotating disk 6 swings to one end of the control groove 38 to limit the rotating disk 6. When adjusting the inclination angle of the metal sheet 2, the metal sheet 2 rotates in the clockwise direction, and the stopper 37 can be rotated in the opposite direction to the other end of the control groove 38 to complete the limiting. After the threaded tube 29 is installed, the drive tube 20 is pulled to both sides so that the mounting ring 5 is opened first. The two ends of the metal sheet 2 are aligned with the plug-in groove 30 for plugging, and then the nut 31 is screwed on to complete the installation and fixation of the entire metal sheet 2. The ball 36 is used to reduce the friction between the metal sheet 2 and the well wall, and it can be suitable for metal sheets 2 with different inclination angles. Example 3

[0038] See also Figure 5-Figure 11 , this embodiment further illustrates the embodiment 1, the limiting mechanism 11 shown in the figure also includes a tension spring 25 fixedly installed on one side of the limiting block 12, the outer wall of the adjusting ring 8 is evenly provided with multiple groups of inflation grooves 26, the limiting block 12 is slidably connected to the inflation groove 26, one end of the tension spring 25 is fixedly connected to the inflation groove 26, the bottom of the adjusting ring 8 is provided with multiple groups of first pipes 27 for connecting the inflation groove 26 and the sleeve 3, and the fixed pipe 1 is provided with a control member 28 for controlling the air pressure state in the inflation groove 26.

[0039] See also Figure 5-Figure 6 The control member 28 shown in the figure includes a driving rod 32 slidably connected to the inner wall of the threaded tube 29, one end of the driving rod 32 is fixedly connected to a second spring 33 fixedly connected to the threaded tube 29, and a second pipe 34 for connecting the threaded tube 29 and the sleeve 3 is opened on the fixed tube 1.

[0040] In this embodiment, when the metal sheet 2 is adjusted to an inclined state, due to the reset force of the clockwork spring 24, loosening the drive tube 20 at this time will not cause the clamping block 10 to immediately be clamped into the limit groove 9 for limiting. At this time, it is necessary to press any one group of drive rods 32 first, and push the gas in the threaded tube 29 into the casing 3 through the second pipe 34, and then transport it to the inflation groove 26 through the first pipe 27, so that the limit block 12 is pushed out and connected with the limit groove 9 to complete the plug-in limit. At this time, loosening the drive tube 20 can make the clamping block 10 pop out directly and plug and fix it with the limit groove 9 to complete the adjustment limit, and then loosen the drive rod 32. During the use of the straightener downhole, pressing the drive rod 32 will cause the limit block 12 to pop out, which does not affect the overall use state of the straightener. This mechanism only plays an auxiliary limit role when adjusting the inclined state of the metal sheet 2.

[0041] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0042] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cementing bow casing centralizer, characterized in that: include: A fixed tube (1) and a plurality of groups of metal sheets (2), wherein the cross-section of the metal sheets (2) is arched, and sleeves (3) are fixedly connected to both upper and lower ends of the fixed tube (1); Also includes: A fixing mechanism (4), the fixing mechanism (4) comprising a mounting ring (5) mounted on the sleeve (3), the outer wall of the fixing tube (1) being evenly rotatably connected to a plurality of sets of rotating disks (6), the fixing mechanism (4) being used to connect the middle of the metal sheet (2) to the rotating disk (6), and to connect and fix the two ends of the metal sheet (2) to the mounting ring (5); An adjusting mechanism (7), the adjusting mechanism (7) comprising an adjusting ring (8) movably sleeved with the inner wall of the sleeve (3), a plurality of groups of limit grooves (9) being provided in the sleeve (3), the adjusting ring (8) being provided with a plurality of groups of clamping blocks (10) capable of being slidably connected with the limit grooves (9) in a vertical direction, the adjusting mechanism (7) being used for releasing the plug-in sliding state between the clamping blocks (10) and the limit grooves (9) when the adjusting ring (8) is rotated, and driving the mounting ring (5) to rotate, thereby changing the positions of the two ends of the metal sheet (2) and adjusting the overall inclination angle of the metal sheet (2); A limiting mechanism (11), the limiting mechanism (11) comprising a plurality of limiting blocks (12) mounted on the adjusting ring (8), the limiting blocks (12) being capable of being plugged into the limiting grooves (9), the limiting mechanism (11) being used to initially limit and fix the relative position between the adjusting ring (8) and the sleeve (3) after the inclination angle of the metal sheet (2) is adjusted, the adjusting mechanism (7) further comprising a first spring (13) fixedly mounted on one side of the clamping block (10), the outer wall of the adjusting ring (8) being evenly provided with a plurality of sliding grooves (14), the clamping block (10) being slidably connected to the inner wall of the sliding groove (14), one end of the first spring (13) being fixedly connected to the sliding groove (14), the adjusting ring (8) being provided with a rotating member (15) for controlling the rotation state of the adjusting ring (8), the sleeve (3) being provided with a rotating member (15) for driving the adjusting ring (8) to rotate. The adjusting ring (8) is reset by a reset member (16), the rotating member (15) comprising a driving ring (17) rotatably connected to one end of the adjusting ring (8), the driving ring (17) being provided with a plurality of arc grooves (18), the clamping block (10) being fixedly connected to a driving shaft (19) capable of being slidably connected to the inner wall of the arc groove (18), the driving ring (17) being coaxially fixedly connected to a driving tube (20), the inner wall of the mounting ring (5) being fixedly connected to the outer wall of the driving tube (20), the reset member (16) comprising a sliding ring (21) installed in the sleeve (3), the sleeve (3) being provided with a guide groove (22), the side surface of the sliding ring (21) being provided with a plurality of guide blocks (23) slidably connected to the guide groove (22), and the outer wall of the sliding ring (21) being fixedly connected to a spring (24) fixedly connected to the adjusting ring (8).

2. A cementing bow casing centralizer according to claim 1, characterized in that: The limiting mechanism (11) further comprises a tension spring (25) fixedly mounted on one side of the limiting block (12); a plurality of groups of air-filling grooves (26) are evenly arranged on the outer wall of the adjusting ring (8); the limiting block (12) is slidably connected to the air-filling grooves (26); one end of the tension spring (25) is fixedly connected to the air-filling grooves (26); a plurality of groups of first pipes (27) for connecting the air-filling grooves (26) and the sleeve (3) are arranged at the bottom of the adjusting ring (8); and a control member (28) for controlling the air pressure state in the air-filling grooves (26) is provided on the fixed pipe (1).

3. A cementing bow casing centralizer according to claim 2, characterized in that: The fixing mechanism (4) further comprises a threaded tube (29) threadably connected to the inner wall of the rotating disk (6); the threaded tube (29) penetrates the middle of the metal sheet (2) and is rotatably connected to the metal sheet (2); the mounting ring (5) is provided with a plurality of groups of insertion grooves (30) capable of being plugged into any one end of the metal sheet (2); the mounting ring (5) is threadably connected to a plurality of groups of nuts (31); the nuts (31) penetrate the metal sheet (2) and are rotatably connected to the metal sheet (2).

4. A cementing bow casing centralizer according to claim 3, characterized in that: The control member (28) comprises a driving rod (32) slidably connected to the inner wall of the threaded tube (29); one end of the driving rod (32) is fixedly connected to a second spring (33) fixedly connected to the threaded tube (29); and a second pipe (34) for connecting the threaded tube (29) and the sleeve (3) is provided on the fixed tube (1).

5. The well cementing bow casing centralizer according to claim 1, characterized in that: A plurality of sets of sleeve blocks (35) are fixedly connected to the metal sheet (2), and balls (36) are rollingly connected inside the sleeve blocks (35).

6. The well cementing bow casing centralizer according to claim 1, characterized in that: A stopper (37) is fixedly connected to the side of the rotating disk (6), and a plurality of control grooves (38) are provided on the side of the fixed tube (1).

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