CN107486642B

CN107486642B - Manifold reversible deformation welding process

Info

Publication number: CN107486642B
Application number: CN201710674315.8A
Authority: CN
Inventors: 高鹏; 石瑞文; 李长龙; 崔英杰; 王泽勇; 李佩
Original assignee: Shengli Oilfield Huabin Industry Co ltd Petroleum Machinery Binzhou Branch
Current assignee: Shengli Oilfield Huabin Industry Co ltd Petroleum Machinery Binzhou Branch
Priority date: 2017-08-09
Filing date: 2017-08-09
Publication date: 2020-11-13
Anticipated expiration: 2037-08-09
Also published as: CN107486642A

Abstract

The invention discloses a header reversible deformation welding process, which comprises the following steps: preparing a die, deforming a header, welding a branch pipe and cutting the header. The welding process is a further improvement and innovation of the conventional method for performing flame heating and mechanical straightening on the deformed valve bank manifold, and performs reverse thinking on welding deformation, so that the manifold welding can be quickly completed to meet the standard requirements, and meanwhile, the purposes of simplifying personnel and saving materials are achieved.

Description

Manifold reversible deformation welding process

Technical Field

The invention belongs to the technical field of welding, and particularly relates to a header reversible deformation welding process.

Background

When the valve bank of the metering room is prefabricated, a header pipe on the valve bank can not freely extend due to the rigid obstruction of a peripheral low-temperature area because a high-temperature area is heated to expand in the cutting and welding processes, and thermoplastic deformation is generated. When the manifold is cooled, the shrinkage of the high-temperature area due to thermoplastic deformation is large, the shrinkage of the low-temperature area is small, the unbalanced shrinkage causes the condensation bending deformation of the manifold, and if measures are not adopted, the whole manifold is likely to be scrapped.

Due to the reasons of rush repair of oil field pipelines, rapid production of new wells and the like, workers need to accelerate construction progress while ensuring engineering quality, the problem of large deformation after the completion of header welding exists in valve bank welding, and the currently adopted integral heating method has long construction period, high labor intensity and high cost. In order to ensure timely production of various projects of an oil field, reduce the operation time, reduce the labor intensity and compress the construction cost, the development of a header anti-deformation welding process is imperative.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a manifold reversible deformation welding process, which is a further improvement and innovation of the conventional method for performing flame heating and mechanical straightening on a deformed valve bank manifold, performs reverse thinking on welding deformation, achieves the purpose of quickly finishing the manifold welding to meet the standard requirements, and achieves the purposes of simplifying personnel and saving materials.

In order to achieve the purpose, the invention provides the following technical scheme:

the header reversible deformation welding process comprises the following steps:

(1) preparing a mould: two steel pipes with the same specification and size are welded together side by side, two rectangular blocks are symmetrically welded on the edge part of one end of each steel pipe to serve as a header fixed end, and the distance between the two rectangular blocks is slightly larger than the outer diameter of a header; the other end of the steel pipe is welded with a fixed bracket as a header control end;

(2) deformation of a header: placing a manifold to be welded on a die, wherein one end of the manifold is welded with two rectangular blocks at a fixed end, the other end of the manifold passes through a fixed bracket at a control end, then placing a jack between the manifold and the fixed bracket, enabling the manifold to deform according to a preset curvature and then be fixed under the action of force between the jack and the fixed bracket, simultaneously calculating the deformation according to the diameter and the length of the manifold, and uniformly placing sizing blocks with different heights between the manifold and the die;

(3) welding branch pipes: according to the specification of the branch pipe to be welded, marking a line above the header, cutting a branch pipe hole, and welding the branch pipe on the header according to a normal welding mode after formation alignment;

(4) cutting a header: when the branch pipe is welded, after the branch pipe is cooled, the manifold is cut off from the die, the manifold of the valve group is deformed under the action of internal stress, and is changed from a bent state to a natural straight state, so that the welding is finished.

In the manifold reversible deformation welding process, the optimal scheme is that the maximum height of the sizing block is in direct proportion to the length of the manifold, the thickness of the pipe wall and the number of branch pipes and in inverse proportion to the diameter of the manifold.

The manifold reversible deformation welding process has the preferable scheme that the surfaces of the manifold and the branch pipe are cleaned before welding, and the drying of a welding surface is ensured.

In the manifold reversible deformation welding process, the preferable scheme is that the welded welding seam is polished and splashes are cleaned.

The invention has the beneficial effects that:

(1) after the welding of the prior welding process, three persons usually spend two days, and the flame heating and adjusting method is adopted to heat the plate to be straight, but after the anti-deformation welding process is adopted, the manifold can directly reach the standard requirement, and no person is needed to perform plate straightening after the welding is finished, so that the labor, the financial resources and the material resources are saved compared with the prior welding process;

(2) the welding process provided by the invention has the advantages of simple welding mode, accurate and standard material selection, capability of ensuring the welding quality of the manifold, scientific and reasonable welding process, low manufacturing cost, reasonable and coordinated parameter collocation and capability of effectively improving the production efficiency.

Drawings

The above and other features, properties and advantages of the present invention will become more apparent from the following description of the embodiments with reference to the accompanying drawings in which like reference numerals denote like features throughout the several views, wherein:

FIG. 1 is a schematic diagram of a manifold reverse deformation pairing.

FIG. 2 is a schematic view of a header after welding is complete.

In the figure: 1-mould, 2-rectangular block, 3-fixed support, 4-jack, 5-manifold, 6-branch pipe and 7-sizing block.

Detailed Description

The invention is further illustrated by the following examples in conjunction with the accompanying drawings:

(1) preparing a mould: two steel pipes 1 with the same specification and size are welded together side by side, two rectangular blocks 2 are symmetrically welded on the edge part of one end of each steel pipe to serve as the fixed end of a manifold, and the distance between the two rectangular blocks is slightly larger than the outer diameter of the manifold; the other end of the steel pipe is welded with a fixed bracket 3 as a header control end;

(2) deformation of a header: placing a manifold 5 to be welded on a die, wherein one end of the manifold is welded with the two rectangular blocks 2 at the fixed end, the other end of the manifold passes through the fixed support 3 at the control end, then placing a jack 4 between the manifold 5 and the fixed support 3, enabling the manifold 5 to deform according to a preset curvature and then to be fixed under the action of force between the jack 4 and the fixed support 3, simultaneously calculating the deformation according to the diameter and the length of the manifold, and uniformly placing sizing blocks 7 with different heights between the manifold and the die;

(3) welding branch pipes: according to the specification of the branch pipe to be welded, marking a line above the header, cutting a branch pipe hole, and welding the branch pipe 6 on the header according to a normal welding mode after formation alignment;

(4) cutting a header: when the branch pipe 6 is welded, after the branch pipe is cooled, the manifold 5 is cut off from the die, the valve bank manifold 5 is deformed under the action of internal stress, and is changed from a bent state to a natural straightening state, and the welding is finished.

Cleaning the surfaces of the manifold 5 and the branch pipe 6 before welding to ensure the dryness of the welding surface; and polishing the welded welding line and cleaning splashes.

The maximum height of the sizing block 7 is in direct proportion to the length of the manifold 5, the thickness of the pipe wall and the number of branch pipes, and in inverse proportion to the diameter of the manifold. The formula is as follows:

wherein, the bending height is the maximum height (m) of the sizing block, and 0.03 is the bending coefficient (curvature).

Take welding a 4 m valve manifold as an example: wherein the specification of the collecting pipe is phi 159 multiplied by 13, and the number of the branch pipes is 6. The shim height should then be:

by adopting the anti-deformation welding process, the header can directly meet the standard requirement, and the plate straightening is not required to be carried out by personnel after the welding is finished, so that the labor, the financial resources and the material resources are saved compared with the existing welding process; the welding process provided by the invention has the advantages of simple welding mode, accurate and standard material selection, capability of ensuring the welding quality of the manifold, scientific and reasonable welding process, low manufacturing cost, reasonable and coordinated parameter collocation and capability of effectively improving the production efficiency.

It should be noted that the specific embodiments are merely representative examples of the present invention, and it is obvious that the technical solution of the present invention is not limited to the above-mentioned examples, and many variations are possible. Those skilled in the art, having the benefit of this disclosure and the benefit of this written description, will appreciate that other embodiments can be devised which do not depart from the specific details disclosed herein.

Claims

1. The header reversible deformation welding process is characterized by comprising the following steps of:

(1) preparing a mould: two steel pipes with the same specification and size are welded together side by side, two rectangular blocks are symmetrically welded on the edge part of one end of each steel pipe to serve as the fixed end of the valve bank manifold, and the distance between the two rectangular blocks is slightly larger than the outer diameter of the valve bank manifold; the other end of the steel pipe is welded with a fixed support as a valve bank manifold control end;

(2) deformation of a header: placing a valve bank manifold to be welded on a die, wherein one end of the valve bank manifold is welded with two rectangular blocks at a fixed end, the other end of the valve bank manifold passes through a fixed support at a control end, then placing a jack between the valve bank manifold and the fixed support, enabling the valve bank manifold to deform according to a preset curvature and then to be fixed under the action of force between the jack and the fixed support, simultaneously calculating deformation according to the diameter and the length of the valve bank manifold, and uniformly placing sizing blocks with different heights between the valve bank manifold and the die;

the maximum height of the sizing block is in direct proportion to the length of the valve bank manifold, the thickness of the pipe wall and the number of branch pipes, and in inverse proportion to the diameter of the valve bank manifold; the formula is as follows:

wherein, the bending height is the maximum height of the sizing block, the unit is m, and 0.03 is the bending coefficient, namely the curvature;

(3) welding branch pipes: according to the specification of a branch pipe to be welded, marking a line above a valve bank manifold, cutting a branch pipe hole, aligning the group, and welding the branch pipe on the valve bank manifold according to a normal welding mode;

(4) cutting a header: when the branch pipe is welded, after the branch pipe is cooled, the valve bank manifold is cut off from the die, the valve bank manifold is deformed under the action of internal stress, and is changed from a bent state to a natural extended state, and the welding is finished.

2. The manifold predeformation welding process of claim 1, wherein the surfaces of the manifold and the branch pipe are cleaned before welding to ensure the welding surface is dry.

3. The manifold reverse deformation welding process of claim 1, wherein the welded seam is ground and spatter is cleaned.