CN-121972845-A - Double-wire electro-gas welding method

CN121972845ACN 121972845 ACN121972845 ACN 121972845ACN-121972845-A

Abstract

The invention relates to the technical field of electro-gas welding, in particular to a double-wire electro-gas welding method, which comprises the steps of arranging a butt joint between a first welding piece and a second welding piece; the welding method comprises the steps of plugging the rear side of the butt joint, carrying out direct current forward connection on a first welding wire, carrying out direct current reverse connection on a second welding wire, arranging the first welding wire and the second welding wire in the butt joint, enabling the first welding wire to be positioned at the rear side of the second welding wire, and controlling the first welding wire and the second welding wire to synchronously and periodically swing along the front-rear direction and synchronously move upwards. According to the double-wire electro-gas welding method, groove machining is not needed, the stability of a welding pool is improved, and the welding quality is ensured.

Inventors

LI JIALIN
WANG MENGGUO
SHAO DANDAN
ZHUO ZHENJIAN
Xie Zukao
Zeng Heming
SUN GUANGJIE

Assignees

中船黄埔文冲船舶有限公司

Dates

Publication Date: 20260505
Application Date: 20260313

Claims (10)

1. A method of double wire electro-gas welding comprising: providing a butt seam between the first weldment and the second weldment; plugging the rear side of the butt joint; The method comprises the steps of performing direct current positive connection on a first welding wire, and performing direct current reverse connection on a second welding wire, wherein the first welding wire and the second welding wire are both arranged in a butt joint, and the first welding wire is positioned at the rear side of the second welding wire; the first welding wire and the second welding wire are controlled to synchronously and periodically swing along the front-back direction and synchronously move upwards.
2. The double wire electro-gas welding method according to claim 1, wherein the first welding wire comprises, by mass, 0.03-0.04% of C, 0.06-0.08% of Si, 0.7-0.9% of Mn, 0.007-0.009% of P, 0.009-0.011% of S, 0.02-0.04% of Ni, 1.03-1.05% of Mo, and the balance of Fe, and the second welding wire comprises, by mass, 0.02-0.03% of C, 0.1-0.12% of Si, 0.8-0.95% of Mn, 0.007-0.009% of P, 0.006-0.008% of S, 2.4-2.6% of Ni, 0.12-0.15% of Mo, and the balance of Fe.
3. The method of twin wire electro-gas welding as defined in claim 1, wherein providing a butt joint between a first weld and a second weld comprises securing the first weld and the second weld with a connector and aligning the first weld and the second weld in a left-right direction and forming the butt joint.
4. The method of twin wire electro-gas welding as defined in claim 3, wherein plugging the back side of the butt joint comprises passing a ceramic liner through the relief hole of the connector, abutting the front side of the ceramic liner against the back sides of the first and second weldments, and plugging the back side of the butt joint.
5. The method of twin wire electro-gas welding as defined in claim 4, wherein a glass cloth is coated on a front side of the ceramic liner and a metal shell is mounted on a rear side of the ceramic liner before the ceramic liner is passed through the relief hole of the connector.
6. The method of double wire electro-gas welding as defined in claim 5, wherein a wedge is inserted between the rear side of the metal shell and the connector after the ceramic liner is passed through the relief hole of the connector.
7. The method of twin wire electro-gas welding as defined in claim 4, wherein controlling the first and second welding wires to synchronously and periodically oscillate in the fore-and-aft direction and to synchronously move upward comprises mounting the first welding wire to a first welding gun and the second welding wire to a second welding gun, the oscillator driving the first welding gun and the second welding gun to synchronously and periodically oscillate in the fore-and-aft direction through a beam, and the lifting trolley driving the oscillator to move upward and driving the copper slider to synchronously move upward against the front side of the butt joint.
8. The dual wire electro-gas stand welding method of claim 7, wherein the first wire has a minimum distance of 15-25mm from the ceramic liner and the second wire has a minimum distance of 10-20mm from the copper slider.
9. The twin wire electro-gas welding method as defined in claim 1, wherein the welding current of the first welding wire is 300-350A, the welding voltage is 30-34V, the welding current of the second welding wire is 380-420A, and the welding voltage is 36-40V.
10. The twin wire electro-gas welding method as defined in claim 1, wherein the swing amplitude of the first and second welding wires is 15-30mm, the end residence time is 1-2s, and the welding speed is 6-15cm/min.

Description

Double-wire electro-gas welding method Technical Field The invention relates to the technical field of electro-gas welding, in particular to a double-wire electro-gas welding method. Background Electro-gas welding is an arc welding method combining consumable electrode gas shielded welding and electroslag welding techniques, and belongs to a welding process in a vertical or near-vertical position. The existing double-wire electro-gas welding method, for example, publication No. CN115026388A and publication No. 2022.9.9, discloses an ultra-large line energy double-wire electro-gas welding method with high transition coefficient, wherein a root side welding wire is kept fixed in the welding process, and a face side welding wire swings in a zigzag manner in a reciprocating manner along the depth direction and the width direction of a groove. The prior art has at least the following defects that a, two welding wires are connected in a direct current reverse mode (the welding wires are connected with an anode and a workpiece cathode), the directions of electromagnetic fields generated by the two electrified welding wires and the two welding arcs are the same, mutual repulsive interference is generated, and the stability of the welding arcs and a welding pool is adversely affected. b. Because the root side welding wire does not swing and is far away from the edge of the groove, the arc heating area cannot effectively cover the root of the groove, and in order to ensure fusion of the periphery of the root of the groove, the welding current and the welding voltage of the root side welding wire have to be greatly improved, so that the welding heat input is obviously increased, the coarsening of the weld metal and the heat affected zone tissues is caused, and the mechanical property is reduced along with. In addition, lack of swing of the root side welding wire means that stirring action of an electric arc on a molten pool is weakened, temperature gradient of the molten pool is increased (heat distribution is uneven), uniformity of a crystallized welding seam structure is poor, harmful impurities (such as S, P) in the welding pool are difficult to uniformly distribute or float upwards and escape, the harmful impurities are more easily gathered to a central area of the welding seam, regional segregation is formed, sensitivity of the welding seam to heat cracks generated in the later stage of crystallization is improved, and finally welding quality is influenced. Disclosure of Invention The invention aims to provide a double-wire electro-gas welding method, which does not need groove processing, improves the stability of a welding pool and ensures the welding quality. In order to achieve the above object, the present invention provides a double wire electro-gas welding method comprising: providing a butt seam between the first weldment and the second weldment; plugging the rear side of the butt joint; The method comprises the steps of performing direct current positive connection on a first welding wire, and performing direct current reverse connection on a second welding wire, wherein the first welding wire and the second welding wire are both arranged in a butt joint, and the first welding wire is positioned at the rear side of the second welding wire; the first welding wire and the second welding wire are controlled to synchronously and periodically swing along the front-back direction and synchronously move upwards. In some embodiments, the first welding wire comprises, by mass, 0.03-0.04% of C, 0.06-0.08% of Si, 0.7-0.9% of Mn, 0.007-0.009% of P, 0.009-0.011% of S, 0.02-0.04% of Ni, 1.03-1.05% of Mo, and the balance of Fe, and the second welding wire comprises, by mass, 0.02-0.03% of C, 0.1-0.12% of Si, 0.8-0.95% of Mn, 0.007-0.009% of P, 0.006-0.008% of S, 2.4-2.6% of Ni, 0.12-0.15% of Mo, and the balance of Fe. In some embodiments, disposing a butt seam between a first weld and a second weld includes securing the first weld and the second weld with a connecting member and aligning the first weld and the second weld in a left-right direction and forming the butt seam. In some embodiments, plugging the back side of the butt seam includes passing a ceramic liner through the relief hole of the connector, abutting the front side of the ceramic liner against the back sides of the first and second weldments, and plugging the back side of the butt seam. In some embodiments, before the ceramic liner is passed through the relief holes of the connector, the front side of the ceramic liner is covered with glass fiber cloth, and the rear side of the ceramic liner is provided with a metal shell. In some embodiments, after passing the ceramic liner through the relief hole of the connector, a wedge is inserted between the rear side of the metal shell and the connector. In some embodiments, controlling the first welding wire and the second welding wire to synchronously and periodically oscillate in the front-back direction and s