Integral casing centralizer and manufacturing method

Abstract

The invention relates to the technical field of well cementation tools, and particularly discloses an integral casing centralizer and a manufacturing method. According to the technical scheme, the centralizer comprises a first pipe hoop, a second pipe hoop and first centralizing bodies, one ends of the first centralizing bodies are fixedly connected with the first pipe hoop, the other ends of the first centralizing bodies are fixedly connected with the second pipe hoop, and the multiple first centralizing bodies are evenly distributed between the first pipe hoop and the second pipe hoop. The righting device has the advantages that the two ends of the righting body are in slope transition, and the righting device can climb and pass smoothly when steps exist in an open hole; the spiral centralizing body can bear large lateral force, when the lateral force reaches the preset strength, the spiral centralizing body with the through hole is subjected to yield damage and passes through a clamping point, and therefore under the condition that the large lateral force is guaranteed, the situation that a casing pipe is jammed can be effectively reduced, and the spiral centralizing body is suitable for well cementation construction of a deep well and a well with a hard well wall, and the construction efficiency is improved. The method is especially suitable for well cementation of highly-deviated wells and horizontal wells.

Description

Technical Field

[0001] The invention relates to the technical field of cementing tools, and in particular to an integral casing centralizer and a manufacturing method thereof. Background Art

[0002] At present, with the rapid development of oil exploration and development technology, many complex wells such as deep wells, small clearance wells, and large displacement wells have emerged, especially the complex wellbores with shrinking diameter and hard well walls. Conventional casing centralizers include elastic casing centralizers and rigid casing centralizers. Elastic casing centralizers are easy to be put into complex or small wellbores due to their variability, but the casing centralizer has a small casing centralizer force and poor casing centralizer effect. Rigid casing centralizers have high strength, are not easy to damage, and can provide a large centralizer force. However, since sufficient clearance must be maintained with the wellbore or outer casing, the centralizer effect is poor and it is difficult to pass through complex wellbores with shrinking diameter.

[0003] Therefore, in order to improve the above situation, it is necessary to propose an integral casing centralizer to overcome the above technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide an integral casing centralizer and a manufacturing method to address the above-mentioned defects in the prior art, thereby solving the technical problem that the elastic solid centralizer has low centralizing force, and the rigid integral centralizer has a large centralizing force but is difficult to pass through complex well conditions such as the wellbore is narrowed.

[0005] The present invention provides an integrated casing centralizer, comprising a first pipe hoop, a second pipe hoop and a first centralizing body, wherein one end of the first centralizing body is fixedly connected to the first pipe hoop, and the other end is fixedly connected to the second pipe hoop, and a plurality of first centralizing bodies are evenly distributed between the first pipe hoop and the second pipe hoop, the first pipe hoop comprises a pipe hoop body, an inner cavity is provided on the inner side of the pipe hoop body, a plurality of positioning protrusions are evenly distributed on the outer lower part of the pipe hoop body, and the second pipe hoop has the same structure as the first pipe hoop and is symmetrically arranged; The first straightening body comprises a first straightening body main body, which is a straight arc-shaped body, with first flat end faces provided at the upper and lower ends of the first straightening body main body, with flat faces provided at the left and right sides of the first straightening body main body, with arc faces provided on the inner side of the first straightening body main body, with positioning grooves provided at the upper and lower ends of the inner side of the first straightening body main body, with a strip-shaped semi-arc face provided in the middle of the outer side of the first straightening body main body, with the semi-arc face and the flat faces on the left and right sides being smoothly transitioned through arc transition faces, with a first through hole provided inside the first straightening body main body near the outer semi-arc face, with an oblique cone face provided between the first flat end faces at the upper and lower ends and the semi-arc face.

[0006] Preferably, the first centralizing body is an elastic centralizing body, the number of the first centralizing bodies is 5, the number of the positioning protrusions is 5 on the first pipe hoop and the number of the second pipe hoop respectively, and the positioning protrusions cooperate with the positioning grooves.

[0007] Preferably, the positioning groove of the first centralizing body is positioned and matched with the positioning protrusions at both ends of the first pipe hoop and the second pipe hoop, and then welded and fixedly connected.

[0008] Preferably, it also includes a clamping assembly for clamping the first straightening body when processing the first through hole, the clamping assembly includes a disc, a fixed block is fixedly provided on the left side of the upper end of the disc, two rows of first threaded through holes are opened on the right side of the upper end of the disc, and an adjustment assembly is movably provided on the upper side of the first threaded through hole.

[0009] Preferably, the fixing block is laterally provided with a plurality of second threaded through holes, and first fastening bolts are provided inside the second threaded through holes.

[0010] Preferably, a V-shaped end face is provided on the left side of the above-mentioned adjustment component, and a first fastening groove, an adjustment groove and a second fastening groove are respectively opened on the right side of the adjustment component, the lower sides of the first fastening groove and the second fastening groove correspond to the positions of the two rows of first threaded through holes opened on the right side of the disk, the inner sides of the first fastening groove and the second fastening groove are respectively equipped with a second fastening bolt and a fastening threaded retaining ring, and the inner side of the adjustment groove is equipped with an adjusting threaded retaining ring and an adjusting bolt.

[0011] A method for manufacturing an integral casing centralizer comprises the following steps: S1: Pipe clamp cutting: The first pipe clamp and the second pipe clamp are made by cutting thick-walled steel pipes through a sawing machine; S2: Manufacturing of pipe clamp positioning protrusions: five positioning protrusions of the first pipe clamp and the second pipe clamp are processed by a milling machine; S3: Production of the first centralizing body: A thick-walled tube is used to cut by laser into a strip-shaped straight arc-shaped body with flat end faces at both ends and flat surfaces on both sides; S4: Forming processing of the outer side of the first centralizing body: using a forming milling cutter to process the semicircular arc surface and the arc transition surface on the outer side of the first centralizing body; S5: Processing of through holes: put the disc of the clamping assembly into the disc caliper of the lathe and fix it, put one end of the first straightening body into the V-shaped end surface of the adjusting assembly, adjust the position of the first straightening body through the adjusting bolt in the adjusting groove, stop after reaching the set size, and tighten the adjusting bolt, further tighten the second fastening bolt arranged in the first fastening groove and the second fastening groove, tighten the first fastening bolt in the second threaded through hole of the fixing block, so that the first straightening body is fixed on the V-shaped end surface of the adjusting assembly, and the other end of the first straightening body is connected to the drill bit or reamer on the tailstock of the lathe, and the first through hole is processed; S6: Processing of the oblique conical surface and the positioning groove: using a vertical milling machine to process the oblique conical surfaces at both ends of the outer side of the first centralizing body and the positioning grooves at both ends of the inner side of the first centralizing body; S7: Assembling the centralizer: assembling the five first centralizers and the first pipe clamp and the second pipe clamp through the positioning groove and the positioning protrusion, and fixing them by welding; S8: Heat treat the formed centralizer, and after cooling, perform sandblasting and apply anti-rust paint.

[0012] Another integral casing straightener mentioned in the present invention comprises a third pipe hoop, a fourth pipe hoop and a spiral straightening body, wherein one end of the spiral straightening body is fixedly connected to the outer circumferential surface of the third pipe hoop, and the other end is fixedly connected to the outer circumferential surface of the fourth pipe hoop, and the spiral straightening body is connected to the outer circumferential surfaces of the third pipe hoop and the fourth pipe hoop by welding.

[0013] Preferably, the above-mentioned spiral straightening body is a second straightening body, and the second straightening body is a spiral straightening rib. The spiral straightening rib is made of rigid material, and a strip circular protrusion is provided on the outer side of the spiral straightening rib, and a second through hole is provided in the strip circular protrusion. Inclined surfaces are provided from the upper and lower end planes of the spiral straightening rib to the outer strip circular protrusion.

[0014] Preferably, the spiral centralizing body is a third centralizing body, and the third centralizing body is formed by integrally stamping an outwardly convex spiral rib plate from a steel plate, and an arc-shaped cavity is provided on the inner side of the third centralizing body.

[0015] The beneficial effects of the present invention are: The present invention provides a through hole inside the straightening body. In a complex wellbore with a shrinking property and a hard wellbore wall, the present invention can solve the technical problem that the elastic solid straightening body has a low straightening force, and the rigid integral straightening body has a large straightening force but is difficult to pass through the complex wellbore conditions with a shrinking wellbore. The two ends of the straightening body adopt an inclined cone surface with a slope transition, so that it can climb and pass smoothly when encountering a step in the open hole. The spiral straightening body can ensure that it can withstand a large lateral force. When the wellbore is narrowed, the lateral force of the spiral straightening body increases. When the preset lateral force threshold is reached, the spiral straightening body with a through hole will yield and break through the blocking point, thereby effectively reducing the occurrence of casing blocking while ensuring a large lateral force. It is suitable for cementing construction of deep wells and wells with hard well walls, especially for cementing of highly deviated wells and horizontal wells. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional diagram of the first embodiment of the present invention; Figure 2 It is a cross-sectional view of a first embodiment of the present invention; Figure 3 It is a three-dimensional diagram of the first centralizing body of the present invention; Figure 4 The first centralizing body of the present invention is in a fixed clamping state; Figure 5 It is a three-dimensional structural diagram of the clamping assembly of the present invention; Figure 6 It is a perspective view of a second embodiment of the present invention; Figure 7 It is a three-dimensional diagram of the second centralizing body of the present invention; Figure 8 It is a three-dimensional diagram of a third embodiment of the present invention; In the figure: 1, first pipe clamp; 2, first centralizing body; 3, second pipe clamp; 4, clamping assembly; 5, second centralizing body; 7, third centralizing body; 11. pipe clamp body; 12. inner cavity; 13. positioning protrusion; 21. first centralizing body; 22. first through hole; 23. oblique conical surface; 24. positioning groove; 25. first flat end surface; 26. flat surface; 27. arc transition surface; 28. semi-circular arc surface; 41. disk; 411. first threaded through hole; 42. fixing block; 421. first fastening bolt; 422. second threaded through hole; 43. adjustment assembly; 431. second fastening bolt; 432. fastening threaded retaining ring; 433. first fastening groove; 434. adjustment groove; 435. second fastening groove; 436. V-shaped end face; 441. adjustment bolt; 442. adjustment threaded retaining ring; 51. spiral straightening rib; 52. second flat end surface; 53. second through hole; 61. Third pipe clamp; 62. Fourth pipe clamp; 71. Arc-shaped cavity. DETAILED DESCRIPTION

[0017] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0018] Embodiment 1, as Figure 1-Figure 3 As shown, an integral casing centralizer comprises a first pipe hoop 1, a second pipe hoop 3 and a first centralizing body 2, wherein one end of the first centralizing body 2 is fixedly connected to the first pipe hoop 1, and the other end is fixedly connected to the second pipe hoop 3, and a plurality of first centralizing bodies 2 are evenly distributed between the first pipe hoop 1 and the second pipe hoop 3, characterized in that: the first pipe hoop 1 comprises a pipe hoop body 11, an inner cavity 12 is provided on the inner side of the pipe hoop body 11, a plurality of positioning protrusions 13 are evenly distributed on the outer lower part of the pipe hoop body 11, and the second pipe hoop 3 has the same structure as the first pipe hoop 1 and is symmetrically arranged; The first straightening body 2 comprises a first straightening body body 21, which is a straight arc-shaped body. The upper and lower ends of the first straightening body body 21 are provided with first flat end faces 25, the left and right sides of the first straightening body body 21 are provided with flat faces 26, the inner side of the first straightening body body 21 is provided with a circular arc surface, the upper and lower ends of the inner side of the first straightening body body 21 are provided with positioning grooves 24, a strip-shaped semicircular arc surface 28 is provided in the middle of the outer side of the first straightening body body 21, the semicircular arc surface 28 and the flat faces 26 on the left and right sides are smoothly transitioned through circular arc transition surfaces 27, a first through hole 22 is provided inside the first straightening body body 21 near the outer semicircular arc surface 28, and an inclined conical surface 23 is provided between the first flat end faces 25 and the semicircular arc surface 28 at the upper and lower ends.

[0019] The first centralizing body 2 is an elastic centralizing body. The number of the first centralizing bodies 2 is 5. Five positioning protrusions 13 are respectively provided on the first pipe hoop 1 and the second pipe hoop 3. The positioning protrusions 13 match with the positioning grooves 24.

[0020] The positioning grooves 24 of the first centralizing body 21 are positioned and matched with the positioning protrusions 13 at both ends of the first pipe clamp 1 and the second pipe clamp 3, and then are welded and fixedly connected.

[0021] like Figure 4 and Figure 5 As shown, it also includes a clamping assembly 4 for clamping the first straightening body 21 when processing the first through hole 22, and the clamping assembly 4 includes a disc 41, a fixed block 42 is fixedly provided on the left side of the upper end of the disc 41, and two rows of first threaded through holes 411 are opened on the right side of the upper end of the disc 41, and an adjustment assembly 43 is movably provided on the upper side of the first threaded through hole 411.

[0022] The fixing block 42 is laterally provided with a plurality of second threaded through holes 422 , and first fastening bolts 421 are disposed inside the second threaded through holes 422 .

[0023] A V-shaped end face 436 is provided on the left side of the adjustment component 43, and a first fastening groove 433, an adjustment groove 434 and a second fastening groove 435 are respectively provided on the right side of the adjustment component 43, the lower sides of the first fastening groove 433 and the second fastening groove 435 correspond to the positions of the two rows of first threaded through holes 411 provided on the right side of the disc 41, and the inner sides of the first fastening groove 433 and the second fastening groove 435 are respectively provided with a second fastening bolt 431 and a fastening threaded retaining ring 432, and the inner side of the adjustment groove 434 is provided with an adjusting threaded retaining ring 442 and an adjusting bolt 441.

[0024] A method for manufacturing an integral casing centralizer comprises the following steps: S1: Pipe clamp cutting: The first pipe clamp 1 and the second pipe clamp 3 are made by cutting thick-walled steel pipes through a sawing machine; S2: Manufacturing of pipe clamp positioning protrusions: five positioning protrusions 13 of the first pipe clamp 1 and the second pipe clamp 3 are processed by a milling machine; S3: Production of the first centralizing body: A thick-walled tube is used to cut by laser into a strip-shaped straight arc-shaped body with flat end surfaces at both ends and flat surfaces 26 at both sides; S4: Forming processing of the outer side of the first centralizing body: using a forming milling cutter to form a semicircular arc surface 28 and an arc transition surface 27 on the outer side of the first centralizing body 21; S5: Processing of through holes: put the disc 41 of the clamping assembly 4 into the disc caliper of the lathe and fix it, put one end of the first straightening body 21 into the V-shaped end surface 436 of the adjusting assembly 43, adjust the position of the first straightening body 21 through the adjusting bolt 441 in the adjusting groove 434, stop after reaching the set size, and tighten the adjusting bolt 441, further tighten the second fastening bolt 431 arranged in the first fastening groove 433 and the second fastening groove 435, tighten the first fastening bolt 421 in the second threaded through hole 422 of the fixing block 42, so that the first straightening body 21 is fixed on the V-shaped end surface of the adjusting assembly 43, and the other end of the first straightening body 21 is connected to the drill bit or reamer on the tailstock of the lathe, and the first through hole 22 is processed; S6: Processing of the oblique conical surface and the positioning groove: using a vertical milling machine to process the oblique conical surfaces 23 at both ends of the outer side of the first centralizing body 21 and the positioning grooves 24 at both ends of the inner side of the first centralizing body 21; S7: Assembling the centralizer: assembling the five first centralizers 2 and the first pipe clamp 1 and the second pipe clamp 3 through the positioning groove 24 and the positioning protrusion 13, and fixing them by welding; S8: Heat treat the formed centralizer, and after cooling, perform sandblasting and apply anti-rust paint.

[0025] The above-mentioned integral casing centralizer adopts a straight arc-shaped centralizing rib with a first through hole 22, and the two ends of the first centralizing body 21 adopt an inclined conical surface 23 with a slope transition, which can smoothly climb and pass through when encountering steps in the open hole. When the first centralizing body 21 with the first through hole 22 encounters a wellbore reduction, when the strength reaches a preset threshold, it will yield and break and then pass through the stuck point, thereby effectively reducing the occurrence of casing jams. It should be noted that wellbore reduction refers to a slight reduction in the local wellbore diameter, which is limited to the maximum outer diameter size after the yield damage occurs on the outside of the first centralizing body 21, rather than the wellbore diameter being so narrow that the centralizer cannot be lowered.

[0026] Embodiment 2, as Figure 6 and Figure 7 As shown, an integral casing centralizer includes a third pipe hoop 61, a fourth pipe hoop 62 and a spiral centralizer, one end of the spiral centralizer is fixedly connected to the outer circumferential surface of the third pipe hoop 61, and the other end is fixedly connected to the outer circumferential surface of the fourth pipe hoop 62, and the spiral centralizer is connected to the outer circumferential surfaces of the third pipe hoop 61 and the fourth pipe hoop 62 by welding.

[0027] The difference from Example 1 is that the above-mentioned spiral straightening body is a second straightening body 5. Compared with the first embodiment, the second straightening body 5 is a further improvement on the basis of the first straightening body 2. The second straightening body 5 is a spiral straightening rib 51. The spiral straightening rib 51 is made of rigid material. A strip-shaped circular protrusion is provided on the outer side of the spiral straightening rib 51. A second through hole 53 is provided in the strip-shaped circular protrusion. Inclined surfaces are provided from the upper and lower end planes of the spiral straightening rib 51 to the outer strip-shaped circular protrusion.

[0028] The above-mentioned integral casing centralizer adopts a spiral centralizing rib 51 provided with a second through hole 53, which is easy to form a vortex when the casing centralizer is lowered, and is convenient for lowering and centering the casing while satisfying the drag reduction requirement. Since the spiral centralizing rib 51 is made of rigid material, it can ensure that it can withstand a large lateral force. When the lateral force reaches a preset strength, the spiral centralizing rib 51 provided with the second through hole 53 will yield and break and then pass through the stuck point, thereby effectively reducing the occurrence of casing jamming while ensuring a large lateral force, and is particularly suitable for cementing in highly deviated wells and horizontal wells.

[0029] Embodiment 3, as Figure 8As shown, an integral casing centralizer includes a third pipe hoop 61, a fourth pipe hoop 62 and a spiral centralizer, one end of the spiral centralizer is fixedly connected to the outer circumferential surface of the third pipe hoop 61, and the other end is fixedly connected to the outer circumferential surface of the fourth pipe hoop 62, and the spiral centralizer is connected to the outer circumferential surfaces of the third pipe hoop 61 and the fourth pipe hoop 62 by welding.

[0030] The difference from the second embodiment is that the spiral centralizing body is a third centralizing body 7 , which is an outwardly convex spiral rib plate integrally stamped from a steel plate, and an arc-shaped cavity 71 is provided inside the third centralizing body 7 .

[0031] The above-mentioned integral casing centralizer adopts a hollow spiral rib centralizer structure, which can significantly reduce the friction and rotation torque when the casing is lowered. Since the inner side of the third centralizer 7 is provided with an arc cavity 71, the solid matter at the bottom of the well can be more fully cleaned when the casing is lowered and the displacement effect during cementing can be optimized.

[0032] The above is only a preferred embodiment of the present invention. Any person skilled in the art may modify the present invention by using the above technical solution or modify it into an equivalent technical solution. Therefore, any simple modification or equivalent transformation made according to the technical solution of the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. An integral casing centralizer, comprising a first pipe hoop (1), a second pipe hoop (3) and a first centralizer (2), wherein one end of the first centralizer (2) is fixedly connected to the first pipe hoop (1), and the other end is fixedly connected to the second pipe hoop (3), and a plurality of first centralizers (2) are evenly distributed between the first pipe hoop (1) and the second pipe hoop (3), characterized in that: The first pipe hoop (1) comprises a pipe hoop body (11), an inner cavity (12) is provided on the inner side of the pipe hoop body (11), a plurality of positioning protrusions (13) are evenly distributed on the lower outer side of the pipe hoop body (11), and the second pipe hoop (3) has the same structure as the first pipe hoop (1) and is symmetrically arranged; The first straightening body (2) comprises a first straightening body body (21), the first straightening body body (21) is a straight arc-shaped body, the upper and lower ends of the first straightening body body (21) are provided with first flat end faces (25), the left and right sides of the first straightening body body (21) are provided with flat faces (26), the inner side of the first straightening body body (21) is provided with a circular arc face, the upper and lower ends of the inner side of the first straightening body body (21) are provided with positioning grooves (24), the middle of the outer side of the first straightening body body (21) is provided with a strip-shaped semicircular arc face (28), the semicircular arc face (28) and the flat faces (26) on the left and right sides are smoothly transitioned through circular arc transition faces (27), the first straightening body body (21) is provided with a first through hole (22) near the outer semicircular arc face (28), and an oblique conical face (23) is provided between the first flat end faces (25) and the semicircular arc face (28) at the upper and lower ends.

2. The integrated casing centralizer according to claim 1, characterized in that: The first centralizing body (2) is an elastic centralizing body, the number of the first centralizing bodies (2) is five, five positioning protrusions (13) are respectively provided on the first pipe hoop (1) and the second pipe hoop (3), and the positioning protrusions (13) cooperate with the positioning grooves (24).

3. The integrated casing centralizer according to claim 2, characterized in that: The positioning groove (24) of the first centralizing body (21) is positioned and matched with the positioning protrusions (13) at both ends of the first pipe hoop (1) and the second pipe hoop (3), and then welded and fixedly connected.

4. The integrated casing centralizer according to claim 3, characterized in that: It also includes a clamping assembly (4) for clamping the first straightening body (21) when machining the first through hole (22), the clamping assembly (4) comprising a disc (41), a fixed block (42) being fixedly provided on the left side of the upper end of the disc (41), two rows of first threaded through holes (411) being provided on the right side of the upper end of the disc (41), and an adjustment assembly (43) being movably provided on the upper side of the first threaded through hole (411).

5. The integrated casing centralizer according to claim 4, characterized in that: The fixing block (42) is laterally provided with a plurality of second threaded through holes (422), and a first fastening bolt (421) is provided inside the second threaded through holes (422).

6. The integrated casing centralizer according to claim 5, characterized in that: The left side of the adjustment component (43) is provided with a V-shaped end surface (436), and the right side of the adjustment component (43) is respectively provided with a first fastening groove (433), an adjustment groove (434) and a second fastening groove (435); the lower sides of the first fastening groove (433) and the second fastening groove (435) correspond to the positions of the two rows of first threaded through holes (411) provided on the right side of the disk (41); the inner sides of the first fastening groove (433) and the second fastening groove (435) are respectively provided with a second fastening bolt (431) and a fastening threaded retaining ring (432); and the inner side of the adjustment groove (434) is provided with an adjustment threaded retaining ring (442) and an adjustment bolt (441).

7. The method for manufacturing an integral casing centralizer according to claim 6, characterized in that: The process includes: S1: pipe clamp cutting: the first pipe clamp (1) and the second pipe clamp (3) are made by cutting thick-walled steel pipes using a sawing machine; S2: Manufacturing of pipe clamp positioning protrusions: machining five positioning protrusions (13) of the first pipe clamp (1) and the second pipe clamp (3) by a milling machine; S3: Production of the first centralizing body: A thick-walled tube is laser cut into a strip-shaped straight arc-shaped body with flat end surfaces at both ends and flat surfaces (26) at both sides; S4: Forming processing of the outer side of the first centralizing body: using a forming milling cutter to form a semicircular arc surface (28) and a circular arc transition surface (27) on the outer side of the first centralizing body (21); S5: Processing of the through hole: the disc (41) of the clamping assembly (4) is placed in the disc caliper of the lathe for fixing, one end of the first straightening body (21) is placed on the V-shaped end surface (436) of the adjusting assembly (43), the position of the first straightening body (21) is adjusted by the adjusting bolt (441) in the adjusting groove (434), the position is stopped after reaching the set size, and the adjusting bolt (441) is tightened, and the second fastening bolt (431) arranged in the first fastening groove (433) and the second fastening groove (435) is further tightened, and the first fastening bolt (421) in the second threaded through hole (422) of the fixing block (42) is tightened, so that the first straightening body (21) is fixed on the V-shaped end surface of the adjusting assembly (43), and the other end of the first straightening body (21) is connected to the drill bit or reamer on the tailstock of the lathe, and the first through hole (22) is processed; S6: Processing of the oblique conical surface and the positioning groove: using a vertical milling machine to process the oblique conical surfaces (23) at both ends of the outer side of the first centralizing body (21) and the positioning grooves (24) at both ends of the inner side of the first centralizing body (21); S7: assembling the centralizer: assembling the five first centralizer bodies (2) with the first pipe clamp (1) and the second pipe clamp (3) through the positioning groove (24) and the positioning protrusion (13), and fixing them by welding; S8: Heat treat the formed centralizer, and after cooling, perform sandblasting and apply anti-rust paint.

8. An integrated casing centralizer, characterized in that: The invention comprises a third pipe hoop (61), a fourth pipe hoop (62) and a spiral straightening body, wherein one end of the spiral straightening body is fixedly connected to the outer circumferential surface of the third pipe hoop (61), and the other end is fixedly connected to the outer circumferential surface of the fourth pipe hoop (62), and the spiral straightening body is connected to the outer circumferential surfaces of the third pipe hoop (61) and the fourth pipe hoop (62) by welding.

9. The integrated casing centralizer according to claim 8, characterized in that: The spiral straightening body is a second straightening body (5), the second straightening body (5) is a spiral straightening rib (51), the spiral straightening rib (51) is made of a rigid material, a strip-shaped circular protrusion is provided on the outer side of the spiral straightening rib (51), a second through hole (53) is provided in the strip-shaped circular protrusion, and inclined surfaces are provided from the upper and lower end planes of the spiral straightening rib (51) to the outer strip-shaped circular protrusion.

10. The integrated casing centralizer according to claim 8, characterized in that: The spiral centralizing body is a third centralizing body (7). The third centralizing body (7) is an outwardly convex spiral rib plate integrally stamped and formed from a steel plate. An arc-shaped cavity (71) is provided on the inner side of the third centralizing body (7).

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