WO2016106484A1

WO2016106484A1 - Integrated elastic centralizer and manufacturing method thereof

Info

Publication number: WO2016106484A1
Application number: PCT/CN2014/095270
Authority: WO
Inventors: 娄来柱
Original assignee: 娄来柱
Priority date: 2014-12-29
Filing date: 2014-12-29
Publication date: 2016-07-07

Abstract

Disclosed are an integrated elastic centralizer and a manufacturing method thereof, the centralizer comprising a cylindrical centralizer body (1), wherein several rectangular through-holes (2) of the same size are arranged on a pipe wall of the centralizer body around the axis as the center, with equal distances between adjacent rectangular through-holes, and vertical pipe walls formed between the adjacent rectangular through-holes serve as centering strips (3) which arch outwards to be in the form of a smooth arc. The integrated elastic centralizer has a high structural strength and strong reliability, and is easy to put into place in a downhole; can adapt to more harsh working environments to reduce downhole accidents caused by the failure of the centralizer; and has smooth-arc centering strips to reduce the friction and wear with other components during use.

Description

Method for manufacturing integral elastic centralizer and elastic centralizer

Technical field

The present application relates to an elastic centralizer, and more particularly to a method for manufacturing an integral elastic centralizer and an elastic centralizer.

Background technique

The elastic centralizer is mainly used in oil cementing operations, so that the downhole oil casing can be centered in the wellbore, and its performance has a great influence on the safety and quality of work. The elastic centralizers in the prior art are monolithic, woven, etc., although the braided elastic centralizer is manufactured to be lower, but the overall strength is low, and there is a risk of falling off under poor downhole conditions, and the existing whole Most of the elastic centralizers are physically cut by the alloy steel plate and then rolled into a tubular shape by the coiling plate. During the winding process, the two types of butt joints are welded together to form a whole, and the welding method is adopted. Two straight edges are directly butt welded, while others are machined at different locations to increase the contact area of the two butt edges of the butt weld to increase the strength of the weld. However, no matter how it is handled, there is always a problem with the integral elastic centralizer produced by the coil welding: there is a potential weak strip at the weld, and there is a risk of cracking of the weld point under complicated downhole conditions, once the weld point Cracking will bring serious potential hazards to the next step. In addition, the existing integral elastic centralizer processing process makes the internal stress distribution of the centralizer uneven during the processing, which also causes the product performance to decline.

Application content

One of the objects of the method for manufacturing the integral elastic centralizer and the elastic centralizer is to solve the problem that the integral elastic centralizer has a weak weld strip in the prior art, and at the same time improve the manufacturing process of the elastic centralizer to enhance its use. performance.

The present application adopts the following technical solution: an integral elastic centralizer comprising a circular tubular centralizer body, and a plurality of rectangular rectangles of the same size are arranged around the axis of the central wall of the centralizer body The through hole has the same spacing between the adjacent rectangular through holes, and the vertical pipe wall formed between the adjacent rectangular through holes is a righting strip, and the reinforcing strip is arched outward to form a smooth arc shape.

Wherein, the main body of the centralizer is made of spring steel material and seamless steel pipe.

The number of the righting bars is 3-8.

A method for manufacturing an elastic centralizer includes the following steps:

S101: providing a seamless steel pipe, and forming a plurality of rectangular through holes around the wall of the seamless steel pipe, requiring the same spacing between adjacent rectangular through holes, and the pipe wall between the adjacent rectangular through holes is a righting strip;

S102: in normal temperature state, shaping the workpiece after the hollow stamping, so that the whole straightening strip is smoothly arched outward;

S103: heat-treating the entire workpiece after the finishing process.

Wherein, before step S101, the method further comprises the steps of: finishing the inner diameter, the outer diameter, and the flatness of the end surface of the seamless steel pipe.

The beneficial effects of the present application are:

1. The true integrated structure, without any separate components or welded parts, high structural strength, high reliability, and easy to place the device in the well.

2, can adapt to a more severe working environment, greatly reducing the underground accident caused by the failure of the centralizer.

3. The arc of the righting strip is smooth, reducing the resistance to the running in the process, which is more conducive to the smooth entry of the casing string.

DRAWINGS

1 is a schematic structural diagram of an initial state of an embodiment of the present application;

2 is a schematic structural diagram of the embodiment of the present application after step S101;

FIG. 3 is a schematic structural diagram of the embodiment of the present application after step S102.

Number in the figure:

1-Mainizer main body 2-rectangular through hole 3-righting strip.

detailed description

The specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

In the following description, numerous specific details are set forth in order to facilitate a full understanding of the application, but the invention may be practiced in other ways than those described herein, and those skilled in the art can do without departing from the scope of the application. The invention is not limited by the specific embodiments disclosed below.

The present application is described in detail in conjunction with the drawings. In the detailed description of the embodiments of the present application, for the convenience of description, the sectional view of the structure of the device will not be partially enlarged, and the schematic is only an example, which should not be limited herein. The scope of protection of this application. In addition, the actual three-dimensional dimensions of length, width and depth should be included in the actual production.

Referring to FIG. 1 to FIG. 3, an embodiment of the present application provides an integral elastic centralizer comprising a circular tubular centralizer body 1 , and a plurality of circumferentially centered on the wall of the centralizer body 1 The rectangular through holes 2 of the same size have the same spacing between the adjacent rectangular through holes 2, and the vertical pipe wall formed between the adjacent rectangular through holes 2 is the righting strip 3, and the reinforcing strips 3 are outwardly arched to form a smooth shape. The arc shape is due to the special working environment of the elastic centralizer, and the centralizer body 1 is a seamless steel pipe made of spring steel.

Preferably, the number of the righting bars is 3-8.

Referring to FIG. 1 to FIG. 3, the integral elastic centralizer provided by the embodiment of the present application is manufactured by the following steps:

S103: heat-treating the entire workpiece after the finishing process.

Wherein, preferably, the seamless steel pipe is finished before step S101 to meet the requirements of the inner diameter, the outer warp and the end surface flatness, and the seamless steel pipe structure after finishing is as shown in FIG. 1 .

First, in step S101, the rectangular through hole 2 is processed circumferentially on the wall of the seamless steel pipe, and the adjacent moment The pipe wall between the through holes 2 is the righting strip 3. According to the size, process and work requirements of the centralizer, the number of the righting bars can be changed between 3 and 8. The structure after the hollowing stamping process of S101 is shown in Fig. 2. Shown.

Then, step S102 is performed, that is, the seamless steel pipe after the hollow stamping is shaped under normal temperature conditions, and a special mold is inserted into the steel pipe to apply an outward force to the centering strip 3, and at the upper end of the main body 1 is applied. The vertical downward force exerts a vertical upward force on the lower end of the main body 1 so that the central strip 3 is smoothly arched outwardly to form a smooth arch shape, wherein the arc of the righting strip 3 is arched It can be determined according to the needs of the process, and the structure completed by the integer is shown in Figure 3.

Finally, step S103 is performed to heat-treat the processed workpiece as a whole.

The integral elastic centralizer provided by the embodiment of the present application has no weak points at all, and the overall elastic centralizer manufactured by the traditional manufacturing process greatly improves the structural strength and has higher product reliability.

Numerous specific details are set forth in the above description in order to provide a thorough understanding of the application. However, the above description is only a preferred embodiment of the present application, and the present application can be implemented in many other ways than the description, and thus the present application is not limited by the specific embodiments disclosed above. At the same time, any person skilled in the art can make many possible changes and modifications to the technical solutions of the present application by using the methods and technical contents disclosed above, or modify the equivalent implementation of equivalent changes without departing from the scope of the technical solutions of the present application. example. Any simple modifications, equivalent changes, and modifications made to the above embodiments in accordance with the technical spirit of the present application are still within the scope of the technical solutions of the present application.

Claims

An integral elastic centralizer comprising a circular tubular centralizer body, wherein a plurality of rectangular through holes of the same size are arranged around the axis of the central wall of the centralizer body, and the spacing between adjacent rectangular through holes Similarly, the vertical tube wall formed between the adjacent rectangular through holes is a righting strip, and the righting strip is arched outward to form a smooth curved shape.
The integral elastic centralizer according to claim 1, wherein the centralizer main body is a seamless steel pipe made of spring steel material.
A one-piece elastic centralizer according to claim 1, wherein the number of the righting bars is 3-8.
A method for manufacturing an elastic centralizer includes the following steps:

S101: providing a seamless steel pipe, and forming a plurality of rectangular through holes around the wall of the seamless steel pipe, requiring the same spacing between adjacent rectangular through holes, and the pipe wall between the adjacent rectangular through holes is a righting strip;

S102: in normal temperature state, shaping the workpiece after the hollow stamping, so that the whole straightening strip is smoothly arched outward;

S103: heat-treating the entire workpiece after the finishing process.
The method of manufacturing an elastic centralizer according to claim 4, further comprising the step of finishing the inner diameter, the outer diameter, and the end surface flatness of the seamless steel pipe before the step S101.