CN-121988853-A - Processing method for lining with complex shape lining of metal pipe by utilizing internal pressure

CN121988853ACN 121988853 ACN121988853 ACN 121988853ACN-121988853-A

Abstract

The invention discloses a processing method of lining with a complex shape on a metal pipe by utilizing internal pressure, which comprises the steps of processing the metal pipe and the lining layer, wherein the shape of the outer wall of the lining layer is consistent with that of the inner wall of the metal pipe, a certain gap can be formed between the metal pipe and the lining layer after the metal pipe and the lining layer are assembled, the lining layer is arranged in the metal pipe, two ends of the lining layer are sealed after vacuum is extracted between the metal pipe and the lining layer, so that an interlayer between the metal pipe and the lining layer is kept in a vacuum state, end covers are welded at the two ends of the metal pipe, a medium is packaged in the metal pipe, the metal pipe is heated to raise the temperature and the pressure of the medium in the metal pipe, diffusion welding is carried out on a part where the outer wall of the lining layer is contacted with the inner wall of the metal pipe after the metal pipe is kept warm and pressure is maintained for a period of time, and the metal pipe is cooled, and the end part is processed and removed to obtain a finished pipe with the lining layer which is tightly attached. The method utilizes the internal pressure generated by the medium to tightly bond the inner liner and the metal pipe and fuses the inner liner and the metal pipe into a whole through diffusion welding, thereby realizing the inner liner with a complex shape in the inner liner of the metal pipe.

Inventors

JIA CHUAN
Yue Nina
HUANG YANPING
ZHAO XUEBIN
GONG HOUJUN
ZAN YUANFENG
YE LV

Assignees

中国核动力研究设计院

Dates

Publication Date: 20260508
Application Date: 20260310

Claims (12)

1. A method for processing a lining with a complex shape on a metal pipe lining by utilizing internal pressure, which is characterized by comprising the following steps: firstly, processing a metal pipe (1) and an inner liner (2), wherein the shape of the outer wall of the inner liner (2) is consistent with the shape of the inner wall (11) of the metal pipe (1), and a certain gap can be formed between the inner wall and the inner wall after the inner liner is assembled; step two, the lining layer (2) is arranged in the metal tube (1), and after the vacuum is extracted between the metal tube (1) and the lining layer (2), the two ends of the metal tube are sealed, so that an interlayer between the metal tube (1) and the lining layer (2) is kept in a vacuum state; Thirdly, welding an end cover (5) at one end of the metal tube (1), filling a medium (6) into the metal tube (1), and welding the end cover (5) at the other end of the metal tube (1) to form a sealing space inside the metal tube (1); Heating the metal tube (1) to raise the temperature and the pressure of an internal medium (6), compressing the inner liner (2) from the inside to enable the outer wall (21) of the inner liner to be closely attached to the inner wall (11) of the metal tube (1), and performing diffusion welding on the contact part between the outer wall (21) of the inner liner (2) and the inner wall (11) of the metal tube (1) after heat preservation and pressure maintaining for a period of time to form a tight joint surface; and fifthly, cooling the metal pipe (1), and processing and removing the end part to obtain a finished pipe (7) closely attached to the inner liner.
2. The method for processing the lining with the complex shape by utilizing the internal pressure in the metal tube according to the claim 1, wherein in the step one, after the lining layer (2) is assembled with the metal tube (1), a gap formed between the lining layer and the metal tube (1) is smaller than 0.1mm.
3. The method for processing the lining with the complex shape by utilizing the internal pressure in the metal tube according to the claim 1, wherein in the step two, the interlayer vacuum degree between the outer wall (21) of the lining layer (2) and the inner wall (11) of the metal tube (1) is lower than 10 -3 Pa.
4. The method for processing the lining with the complex shape by utilizing the internal pressure in the metal tube according to the claim 1, wherein in the step two, the two ends of the lining layer (2) and the inner wall (11) of the metal tube (1) are sealed by welding.
5. The method for processing the lining with the complex shape by using the internal pressure in the metal tube according to the claim 1, wherein the medium (6) in the third step is gas or liquid, and the medium (6) and the lining layer (2) are kept chemically stable.
6. The method of lining a metal tube with a complex-shaped lining using internal pressure according to claim 5, wherein the medium (6) is in a partially filled state or in a filled state within the metal tube (1).
7. The method of lining a metal tube with a complex-shaped lining using internal pressure according to claim 1, wherein the shape of the inner wall (11) of the metal tube (1) includes, but is not limited to, a round shape or a square shape.
8. The method for processing the lining with the complex shape by using the internal pressure in the metal tube according to the claim 1, wherein the shape of the inner wall of the lining layer (2) comprises a polygon or a combination of various patterns.
9. The method for processing a lining with a complex shape using internal pressure in a metal pipe according to claim 1, wherein the material of the inner lining (2) comprises a metallic material or a non-metallic material.
10. The method for processing the lining with the complex shape by utilizing the internal pressure in the metal pipe according to the claim 1, wherein the outer wall (21) of the lining layer (2) is provided with a groove, and the depth of the groove is not more than the thickness of the lining layer at the position.
11. The method for processing the lining with the complex shape by utilizing the internal pressure in the metal tube according to the claim 1, wherein the axial length of the lining layer (2) is smaller than the axial length of the metal tube (1).
12. The method for processing the lining with the complex shape by utilizing the internal pressure in the metal tube according to the claim 1, wherein the metal tube (1) in the step five is cooled and then the tube section between the end cover (5) and the end part of the lining layer (2) is removed by machining.

Description

Processing method for lining with complex shape lining of metal pipe by utilizing internal pressure Technical Field The invention relates to the technical field of pipeline processing, in particular to a processing method for lining a metal pipe with a lining layer in a complex shape by utilizing internal pressure. Background Common metal pipes (round or special pipes) require lining of the inner wall with various liners for various reasons, so that the inner and outer layers of the pipe meet different performance requirements. There are various methods for manufacturing the pipeline, and the lining layer is usually welded or mechanically assembled and then expanded to be attached to the inner wall of the metal pipe, and the method has simple manufacturing process, but the inner wall and the outer wall of the lining layer are usually smooth structures, as shown in fig. 1. As the internal machining of the lining layer or other more complex shapes is required in certain use cases, as shown in fig. 2. When it is required to line the inner wall of the metal pipe with an inner liner layer of a more complex shape, the conventional processing method is difficult to process, and the method of welding or expansion joint after mechanical assembly has a plurality of limitations. Disclosure of Invention The invention aims to provide a processing method for lining a metal pipe with a lining layer with a complex shape by utilizing internal pressure, which aims at solving the problem that the lining layer with the complex shape is difficult to be arranged on the inner wall of the metal pipe. The invention is realized by the following technical scheme: The invention provides a processing method for lining a metal pipe with a lining layer in a complex shape by utilizing internal pressure, which comprises the following steps: Step one, processing a metal pipe and an inner liner, wherein the shape of the outer wall of the inner liner is consistent with that of the inner wall of the metal pipe, and a certain gap can be formed between the two after the assembly; Step two, the lining layer is arranged in the metal tube, and after the vacuum is extracted between the metal tube and the lining layer, two ends of the metal tube and the lining layer are sealed, so that an interlayer between the metal tube and the lining layer is kept in a vacuum state; thirdly, welding an end cover at one end of the metal pipe, filling a medium into the metal pipe, and welding the end cover at the other end of the metal pipe to form a sealing space in the metal pipe; Heating the metal tube to raise the temperature and pressure of the internal medium, compressing the inner liner layer from the inside to enable the outer wall of the inner liner layer to be closely attached to the inner wall of the metal tube, and performing diffusion welding on the contact part between the outer wall of the inner liner layer and the inner wall of the metal tube after heat preservation and pressure maintaining for a period of time to form a tight joint surface; And fifthly, cooling the metal pipe, and processing and removing the end part to obtain a finished pipe closely attached to the inner liner. As a further aspect of the present invention, in the first step, after the lining layer and the metal tube are assembled, a gap formed between the lining layer and the metal tube is less than 0.1mm. As a further scheme of the invention, the vacuum degree of the interlayer between the outer wall of the inner liner layer and the inner wall of the metal tube in the second step is lower than 10 -3 Pa. As a further scheme of the invention, in the second step, the two ends of the inner liner layer and the inner wall of the metal tube are welded to form a seal. As a further scheme of the invention, the medium in the third step is gas or liquid, and chemical stability is kept between the medium and the inner liner. As a further development of the invention, the medium is in a partially filled state or in a filled state in the metal tube. As a further aspect of the present invention, the shape of the inner wall of the metal pipe includes, but is not limited to, a circular shape or a square shape. As a further aspect of the present invention, the inner wall shape of the inner liner layer includes a polygon or a combination of various patterns. As a further aspect of the present invention, the material of the inner liner layer includes a metal material or a non-metal material. As a further scheme of the invention, the outer wall of the inner liner is provided with a groove, and the depth of the groove does not exceed the thickness of the inner liner at the position. As a further aspect of the present invention, the axial length of the inner liner is smaller than the axial length of the metal pipe. As a further scheme of the invention, after the metal pipe in the step five is cooled, the pipe section between the end cover and the end part of the inner liner is removed through machining