CN220319491U

CN220319491U - Casing pipe rigid centralizer

Info

Publication number: CN220319491U
Application number: CN202321821349.2U
Authority: CN
Inventors: 王朋飞; 赵宽心; 杨培峰; 王钻; 白旺东; 郭小合
Original assignee: Tarim Branch Sinopec Zhongyuan Petroleum Engineering Co ltd; Sinopec Oilfield Service Corp; Sinopec Zhongyuan Petroleum Engineering Co Ltd
Current assignee: Tarim Branch Sinopec Zhongyuan Petroleum Engineering Co ltd; Sinopec Oilfield Service Corp; Sinopec Zhongyuan Petroleum Engineering Co Ltd
Priority date: 2023-07-12
Filing date: 2023-07-12
Publication date: 2024-01-09
Anticipated expiration: 2033-07-12

Abstract

The utility model belongs to the technical field of petroleum drilling, and provides a casing rigid centralizer, wherein a plurality of centralizing blocks are circumferentially distributed on the outer side of the wall of a hollow body; adjacent two of the righting segments form an outer channel providing a first passageway for fluid flow; the inner wall of the hollow body is provided with inner runner grooves the same as the centralizing blocks in number, and the inner runner grooves and the outer wall of the sleeve provide a second channel for fluid flow. Because two fluid channels are provided, under the condition that the outer runner groove of the centralizer is blocked and is not communicated with the pump, the pump can be started to circulate through the inner runner groove, annulus sand setting and mud cakes are carried, the annulus cleanliness is improved, and the outer runner groove is gradually opened. The two fluid channels increase the fluid flow area, improve the flow state of well cementation cement paste, improve the annulus displacement efficiency and ensure the well cementation quality. The inner runner groove and the corresponding centralizing block are arranged on the same radial direction, so that the better fluid passing capacity can be maintained in the whole circumferential range.

Description

Casing pipe rigid centralizer

Technical Field

The utility model belongs to the technical field of petroleum drilling, and particularly relates to a casing pipe rigid centralizer.

Background

In petroleum drilling, in order to reach the purpose of drilling and develop hydrocarbon reservoirs, casing is put into the casing separately for many times, and cement seals the stratum which is drilled and encountered. Therefore, whether the sleeve can be smoothly lowered in place or not, whether the well cementation quality can meet the construction requirement of the next time becomes the key of whether the operation is successful after the next time. And with the progressive development of oil and gas exploration to ultra-thin and ultra-deep directions, the continuous proposal of high-difficulty well type such as highly-inclined wells, horizontal wells and the like also increases the contact surface of the sleeve and the well wall, and the problems that the friction resistance of the sleeve is continuously increased, the pump is difficult to open the sleeve to the bottom, the well cementation annulus sealing quality is poor and the like appear.

Casing is put into the long open hole section and the directional well section, the casing is clung to the well wall under the action of gravity, especially sand shale or soft stratum well section, the rigid spiral centralizer is clung to the well wall, along with the casing is put down, well wall sand and mud cakes are scraped, the casing is gradually accumulated in a runner groove, the casing is gradually compacted under the thrust of the lowering, the top through difficulty can appear after the casing is at the bottom, and the phenomenon of normal open pump cannot be realized. In the well cementation process, under the condition that one runner groove is blocked, nearby drilling fluid cannot be effectively replaced, cement stones in an annulus cannot be uniformly distributed and filled, oil gas can gradually upwards flow along a weak point to form a channel, finally, a wellhead is pressurized, well cementation quality is affected, and a well is scrapped seriously.

Thus, the problems that the blockage of the flow passage groove of the casing centralizer is not communicated with the pump, the annular space cannot be effectively replaced to influence the well cementation quality are not completely and effectively solved in the prior art and the method, and the casing centralizer is continuously improved but cannot be fundamentally solved.

Thus, there is a great need for a rigid casing centralizer that addresses this problem.

Disclosure of Invention

The utility model aims to provide a casing pipe rigid centralizer which is strong in adaptability, small in casing pipe lowering friction resistance, smooth in bottom opening of a pump, and high in annulus cleaning efficiency and well cementation displacement efficiency.

In order to achieve the above purpose, the utility model provides a casing rigid centralizer, which comprises a cylindrical hollow body, wherein a plurality of centralizing blocks are uniformly distributed on the outer side of the wall of the hollow body along the circumferential direction, and the maximum outer diameter of each centralizing block is slightly smaller than the inner diameter of a borehole; the outer walls of two adjacent centralizing blocks and the hollow body between the centralizing blocks and the hollow body form an outer flow channel groove for providing a first channel for fluid flow; the inner diameter of the hollow body is slightly larger than the outer diameter of the sleeve body, inner flow channel grooves with the same number as the centralizing blocks are uniformly distributed on the inner wall of the hollow body along the circumferential direction, and the inner flow channel grooves and the outer wall of the sleeve provide a second channel for fluid flow; any one of the inner runner grooves and the corresponding righting block are arranged on the same radial direction.

Preferably, the righting segment and the internal flow channel extend from a first end to a second end of the hollow body.

Preferably, at least three of said righting segments and at least three of said inner runner channels are provided.

Preferably, the righting block and the inner runner channel are each arranged in a right-hand spiral form and are angled at 30 ° to the axis of the hollow body.

Preferably, the hollow body has an integral structure with uniform upper and lower paths.

Preferably, the outer diameters of the upper end and the lower end of the centralizing block are slightly smaller than the outer diameter of the middle section.

Preferably, the cross section of the inner runner groove is trapezoidal.

The casing rigid centralizer provided by the utility model has the advantages that the plurality of centralizing blocks are uniformly distributed on the outer side of the pipe wall of the casing body along the circumferential direction; the outer walls of two adjacent centralizing blocks and the hollow body between the centralizing blocks and the hollow body form an outer flow channel groove for providing a first channel for fluid flow; the inner wall of the hollow body is provided with inner runner grooves with the same number as that of the centralizing blocks along the circumferential direction, and the inner runner grooves and the outer wall of the sleeve provide a second channel for fluid flow. Because two fluid channels are provided, under the condition that the outer runner groove of the centralizer is blocked and is not communicated with the pump, the pump can be started to circulate through the inner runner groove, annulus sand setting and mud cakes are carried, the annulus cleanliness is improved, and the outer runner groove is gradually opened. The two fluid channels increase the fluid flow area, improve the flow state of well cementation cement paste, improve the annulus displacement efficiency and ensure the well cementation quality. The inner runner groove and the corresponding centralizing block are arranged on the same radial direction, so that the better fluid passing capacity can be maintained in the whole circumferential range.

In addition, the integrated rigid centralizer has no other spare and accessory parts, reduces the risk of down-hole falling objects, and has simple manufacturing process and lower processing cost.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present utility model, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic perspective view of a casing rigid centralizer according to an embodiment of the utility model in a non-well-entering state;

FIG. 2 is a schematic top view of the casing rigid centralizer of FIG. 1 in a well-logging configuration.

Reference numerals in fig. 1 to 2 are as follows:

a hollow body 1, an outer runner channel 2, an inner runner channel 3, a centralizing block 4, a well bore 5, a casing 6 and a rigid centralizing device 7.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The core of the utility model is to provide a casing pipe rigid centralizer which has strong adaptability, small casing pipe lowering friction resistance, smooth bottom opening pump, high annulus cleaning efficiency and high well cementation displacement efficiency.

Referring to fig. 1 and 2, fig. 1 is a schematic perspective view of a casing rigid centralizer according to an embodiment of the present utility model in a non-well-entering state; FIG. 2 is a schematic top view of the casing rigid centralizer of FIG. 1 in a well-logging configuration.

In a specific embodiment, the casing rigid centralizer 7 provided by the utility model comprises a cylindrical hollow body 1, wherein a plurality of centralizing blocks 4 are arranged on the outer side of the hollow body 1, and three or more than three centralizing blocks are usually arranged.

The plurality of righting blocks 4 are uniformly distributed circumferentially along the outer wall of the hollow body 1 with a maximum outer diameter slightly smaller than the inner diameter of the borehole 5. The maximum outer diameter of the righting block 4 may be provided in its middle section, i.e. the outer diameters of both its upper and lower end portions are smaller than the outer diameter of its middle section, and the righting block 4 may extend from the first end to the second end of the hollow body 1.

The outer wall of two adjacent righting blocks 4, the outer wall of the hollow body 1 between the two, and the inner wall of the well bore 5 can form an outer runner groove 2, and the outer runner groove 2 provides a first channel for fluid flow.

The hollow body 1 has a structure with uniform upper and lower diameters, and the inner diameter of the hollow body is slightly larger than the outer diameter of the sleeve body 6. A plurality of inner runner grooves 3 are arranged on the inner wall of the hollow body 1, and the number of the inner runner grooves 3 can be set to be consistent with the number of the righting blocks 4.

The inner runner grooves 3 are uniformly distributed on the inner wall of the hollow body 1 in the circumferential direction, and the outer wall of the sleeve 6 provides a second channel for fluid flow.

The inner flow channel groove 3 and the corresponding centralizing block 4 can be arranged in the same radial direction, namely in a position relationship as shown in fig. 2, so that the better fluid passing capacity can be maintained in the whole circumferential range.

The inner runner 3 may also extend from the first end to the second end of the hollow body 1, and may have a trapezoidal cross section.

Further, the centering blocks 4 and the inner flow channel grooves 3 may be arranged in a right spiral form, as shown in fig. 1, at which time it can be seen that the upper ends of the centering blocks 4 and the inner flow channel grooves 3 are offset to the right and the lower ends are offset to the left on the wall surfaces adjacent to the reader. The angle of deviation of the hollow body 1 from the axis of the hollow body 1 may be 30 degrees.

The hollow body 1 may have an integral structure.

In addition, the integral rigid centralizer has no other spare and accessory parts, reduces the risk of down-hole falling objects, and can meet the requirement of continuous rotation of the casing in the casing process under special rotation; the manufacturing process is simple and the processing cost is low.

In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other.

The casing rigid centralizer provided by the utility model is described in detail above. The principles and embodiments of the present utility model have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present utility model and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the utility model can be made without departing from the principles of the utility model and these modifications and adaptations are intended to be within the scope of the utility model as defined in the following claims.

Claims

1. The casing rigid centralizer comprises a cylindrical hollow body (1), and is characterized in that a plurality of centralizing blocks (4) are uniformly distributed on the outer side of the pipe wall of the hollow body (1) along the circumferential direction, and the maximum outer diameter of each centralizing block (4) is smaller than the inner diameter of a borehole (5); the outer walls of two adjacent centralizing blocks (4), the hollow body (1) between the centralizing blocks and the outer wall of the well bore (5) form an outer flow channel (2) for providing a first channel for fluid flow; the inner diameter of the hollow body (1) is larger than the outer diameter of the sleeve body (6), inner flow channel grooves (3) with the same number as the centralizing blocks (4) are uniformly distributed on the inner wall of the hollow body along the circumferential direction, and the inner flow channel grooves (3) and the outer wall of the sleeve body (6) provide a second channel for fluid flow; any one of the inner runner grooves (3) and the corresponding righting block (4) are arranged on the same radial direction.

2. A casing rigid centraliser according to claim 1, wherein the centraliser block (4) and the inner runner channel (3) extend from a first end to a second end of the hollow body (1).

3. A casing rigid centraliser according to claim 2, wherein at least three centraliser blocks (4) and at least three inner runner channels (3) are provided.

4. A casing rigid centraliser according to any of claims 1-3, wherein the centraliser block (4) and the inner runner groove (3) are each arranged in a right-handed helix and are at an angle of 30 ° to the axis of the hollow body (1).

5. A casing rigid centraliser according to claim 4, wherein the hollow body (1) has a unitary structure with uniform upper and lower paths.

6. A casing rigid centraliser according to claim 5, wherein the centraliser block (4) has an outer diameter at the upper and lower ends which is less than the outer diameter of the mid-section.

7. A casing rigid centraliser according to claim 6, wherein the cross section of the inner flow channel (3) is trapezoidal.