CN-116571849-B - Welding method for nickel copper pipe butt joint

CN116571849BCN 116571849 BCN116571849 BCN 116571849BCN-116571849-B

Abstract

The application provides a welding method for butt joint of nickel copper pipes, which uses a manual tungsten argon arc welding process of filler wires, and comprises chamfering the butt joint edges of a first nickel copper pipe and a second nickel copper pipe, wherein the chamfer faces outwards, and the inclination angle is 30 degrees; the method comprises the steps of cleaning the butt joint edges of a first nickel copper pipe and a second nickel copper pipe, adjusting the butt joint seam width of the first nickel copper pipe and the second nickel copper pipe to be within a preset standard width range, forming a circumferential groove with a V shape and a single-side inclination angle of 30 degrees, performing positioning welding, setting argon flow in the nickel copper pipe to be within a preset argon flow range, setting shielding gas argon flow of a welding gun to be within a preset shielding gas flow range, and sequentially performing one-step backing welding, three-step filling welding and one-step cover welding at the circumferential groove according to preset welding voltage, preset welding current, preset welding speed and preset welding path. According to the technical scheme, the deformation of the nickel-copper pipe in the butt joint welding process is effectively reduced, the repair rate is reduced, the welding quality is improved, and the production efficiency is improved.

Inventors

ZHU RUIXIA
LING WEI
YANG LU
YANG JIANJUN
GUAN ZHILI
YANG XINJIE
CAI CHUNMAO

Assignees

江南造船(集团)有限责任公司

Dates

Publication Date: 20260512
Application Date: 20230627

Claims (5)

1. The welding method for the butt joint of the nickel copper pipes is characterized by using a manual tungsten argon arc welding process of filler wires, and comprises the following steps of: S1, chamfering the butt joint edges of a first nickel copper pipe and a second nickel copper pipe, wherein the chamfer faces outwards, and the inclination angle is 30 degrees; s2, cleaning the butt joint edges of the first nickel copper pipe and the second nickel copper pipe; S3, adjusting the widths of butt joints of the first nickel copper pipe and the second nickel copper pipe to be within a preset standard width range, forming a circumferential groove which is V-shaped and has a single-side inclination angle of 30 degrees, and performing positioning welding and fixing; s4, setting argon flow of the nickel copper pipe to be within a preset argon flow range, and setting the shielding gas argon flow of the welding gun to be within a preset shielding gas flow range; S5, sequentially performing one backing welding, three filling welding and one cover welding at a circumferential groove according to preset welding voltage, preset welding current, preset welding speed and preset welding paths, wherein the backing welding forms a backing welding layer, the three filling welding comprises a first filling welding layer, a second filling welding layer and a third filling welding layer, the first filling welding layer, the second filling welding layer and the third filling welding layer are respectively formed, and the cover welding forms a cover welding layer; the first filling welding layer is in contact with the chamfer inclined surface of the first nickel copper pipe, the second filling welding layer is in contact with the chamfer inclined surface of the second nickel copper pipe, the third filling welding layer is positioned between the first filling welding layer and the second filling welding layer, and at least partial areas on two sides of the third filling welding layer cover the first filling welding layer and the second filling welding layer respectively; Setting welding currents with step differences in backing welding, filling welding and cover welding; four positions of three o 'clock, six o' clock, nine o 'clock and twelve o' clock are marked clockwise along the circumferential direction of the circumferential groove, one preset welding path of the backing welding, three filling welding and one preset welding path of the cover welding are the same, and the preset welding path comprises: a first sub-path welded counterclockwise from the six o 'clock position to the three o' clock position; a second sub-path welded clockwise from the six o 'clock position to the nine o' clock position; a third sub-path welded counterclockwise from the three o 'clock position to the twelve o' clock position; A fourth sub-path welded clockwise from the nine o 'clock position to the twelve o' clock position; wherein the preset welding current of the backing welding is 75-80A; The range of the preset welding current of the first filling welding is 85-90A, the range of the preset welding current of the second filling welding is 90-95A, and the range of the preset welding current of the third filling welding is 110-120A; The preset welding current of the cover welding is in the range of 110-120A.
2. The welding method for nickel copper pipe butt joint according to claim 1, wherein the whole welding layer structure formed by the priming welding layer, the first filling welding layer, the second filling welding layer, the third filling welding layer and the cover welding layer is symmetrical with the central surface of the butt joint of the first nickel copper pipe and the second nickel copper pipe, and the central surface is parallel to the end surface of the butt joint of the first nickel copper pipe and the second nickel copper pipe and is positioned in the middle of the butt joint.
3. The welding method for nickel copper pipe butt joint according to claim 1, wherein the second sub-path has at least a predetermined length at six o' clock position overlying the first sub-path; the third sub-path having at least a predetermined length overlying the first sub-path at the three o' clock position; the fourth sub-path having at least a predetermined length overlying the second sub-path at the nine o' clock position; the fourth sub-path overlies the third sub-path for at least a predetermined length at the twelve o' clock position.
4. The method for butt welding of copper nickel pipes according to any one of claims 1-3, wherein the step S3 further comprises adjusting concentricity of the first and second copper nickel pipes to be 1mm or less before the fixing by tack welding.
5. A welding method for butt welding of nickel copper pipes according to any one of claims 1-3, wherein in step S3, the preset standard width is in the range of 2mm-5mm, and in welding, the interlayer temperature is controlled below 100 ℃.

Description

Welding method for nickel copper pipe butt joint Technical Field The application relates to the technical field of nickel-copper tube welding, in particular to a welding method for butt joint of nickel-copper tubes. Background The nickel-copper alloy pipe manufactured by the nickel-copper alloy material (B10) can also be called nickel-copper pipe, and is widely applied to a seawater cooling system. Because of the particularity of the nickel copper pipe, the nickel copper pipe cannot be bent by a pipe bending machine, and the bent joint is generally butted by adopting a nickel copper pipe shaping elbow and the formed circumference butt joint seam is welded. For longer nickel copper pipe system pipelines, multiple sections of nickel copper pipes are also required to be butted. The formed circumference is then welded to the seam. Because the copper-iron-nickel alloy material has a larger linear expansion coefficient, the copper-iron-nickel alloy material is extremely easy to deform under the action of welding thermal cycle. Meanwhile, the number of welding seams (butt seams) is multiplied by using elbow splicing, so that the shrinkage rate is increased, and the deformation problem is aggravated. Therefore, the external dimension of the pipe is ensured to meet the manufacturing requirement and the assembly process requirement, and the welding difficulty of the nickel-copper pipe is realized. Meanwhile, when the current nickel-copper pipe is welded to the joint, the problems of unfused, incomplete welding, slag inclusion, weld flash and the like are easy to occur, air holes, arc-collecting cracks, defects of reduced precision and the like are easy to occur on the surface of the welding seam, and the shooting qualification rate is only about 40%, so that more repair is caused, most of pipes are deformed after repair, and the welding pipe cannot be installed and used, so that a lot of materials and manpower are wasted. Disclosure of Invention The embodiment of the application aims to provide a welding method for butt joint of nickel copper pipes, which can effectively reduce the deformation in the butt joint welding process of the nickel copper pipes, reduce the repair rate, improve the welding quality, relatively improve the production efficiency and shorten the construction period. The application provides a welding method for butt joint of nickel copper pipes, which uses a manual tungsten argon arc welding process of filler wires, and comprises the following steps: S1, chamfering the butt joint edges of a first nickel copper pipe and a second nickel copper pipe, wherein the chamfer faces outwards, and the inclination angle is 30 degrees; s2, cleaning the butt joint edges of the first nickel copper pipe and the second nickel copper pipe; S3, adjusting the widths of butt joints of the first nickel copper pipe and the second nickel copper pipe to be within a preset standard width range, forming a circumferential groove which is V-shaped and has a single-side inclination angle of 30 degrees, and performing positioning welding and fixing; s4, setting argon flow of the nickel copper pipe to be within a preset argon flow range, and setting the shielding gas argon flow of the welding gun to be within a preset shielding gas flow range; and S5, sequentially performing one backing welding, three filling welding and one cover welding at the circumferential groove according to preset welding voltage, preset welding current, preset welding speed and preset welding path, wherein the backing welding forms a backing welding layer, the three filling welding comprises a first filling welding layer, a second filling welding layer and a third filling welding layer, the first filling welding layer, the second filling welding layer and the third filling welding layer are respectively formed, the cover welding forms a cover welding layer, the backing welding layer is positioned at the innermost ring of the circumferential groove, the first filling welding layer, the second filling welding layer and the third filling welding layer completely cover the backing welding layer, and the cover welding layer completely covers the first filling welding layer, the second filling welding layer and the third filling welding layer. In one embodiment, the first filler layer is in contact with the chamfer bevel of the first nickel copper tube, the second filler layer is in contact with the chamfer bevel of the second nickel copper tube, the third filler layer is positioned between the first filler layer and the second filler layer, and at least partial areas on two sides of the third filler layer cover the first filler layer and the second filler layer respectively. In one implementation scheme, the whole welding layer structure formed by the priming welding layer, the first filling welding layer, the second filling welding layer, the third filling welding layer and the cover welding layer is in a symmetrical structure by the central surface of the