High intensity steel gas shielded welding technique method

Abstract

The invention relates to a gas shielded welding technological method of high strength steel, which comprises the following technological steps: (1) a gas shielded welding joint is cut with a dual-V dissymmetrical divided edge at the angle of 60 degrees and the blunted edge of 2mm; (2) welding wires with the nominal strength of 700MPa are adopted for welding and have the tensile strength of a deposited metal of Rm more than or equal to 700MPa; (3) the mixed gas-shielded welding with 20 percent of CO2 plus 80 percent of Ar and argon-rich gas is adopted and no preheating is required before the welding and no heat treatment is carried out after welding; (4) the chemical composition of the welding wires adopted by weight percentage is that: C is 0.04 to 0.12, Si is 0.40 to 0.80, Mn is 1.40 to 2.0, P is less than or equal to 0.020, S is less than or equal to 0.015, Ni is 0.40 to 1.0, Cr is 0.20 to 0.50, Ti is 0.06 to 0.20, Cu is 0.30 to 0.50, B is 0.002 to 0.0079, Als is less than or equal to 0.02. The method of the invention has good welding technological performance, simple operation, convenient application and high efficiency and energy saving, and is quite applicable to the welding of steel used in a high-strength structure in the ocean engineering.

Description

technical field

[0001] The invention relates to a welding method for steel, in particular to a gas shielded welding process for high-strength steel, which is suitable for welding tensile strength R m ≥690MPa grade low-alloy high-strength steel for marine engineering structures. Background technique

[0002] With the rapid development of my country's metallurgical industry and science and technology, the performance of new steel types and new materials has also been continuously improved. In particular, the development and application of modern controlled rolling and controlled cooling technology and microalloying have greatly improved the strength and toughness of low alloy steel. In particular, modern engineering design and marine engineering machinery manufacturing are increasingly developing in the direction of large-scale, high-parameter, and light-weight. Such as: manufacturing of long-span bridge structures, manufacturing of high-parameter pressure vessels and large-...

Examples

Embodiment 1

[0016] Base material: WNQ690 steel plate, the size of the test plate is 600mm×300mm×26m. The gas shielded welding groove adopts double V-shaped asymmetric groove, the groove angle is 60°, and the blunt edge is 2mm.

[0017] Welding material matching: the mechanical properties of the deposited metal are R el =665MPa, R m =735MPa, A=20%, Z=68%, average impact energy A of deposited metal KV (-40°C) = 182J, combined with WNQ690 steel (26mm+26mm) thick plate using rich argon (20% CO 2 +80% Ar) welding process welding.

[0018] Welding process specification: The chemical composition of the welding wire used is: C: 0.04, Si: 0.40, Mn: 1.40, P≤0.020, S≤0.015, Ni: 0.40, Cr: 0.20, Ti: 0.06, Cu: 0.30, B: 0.002, Als≤0.02, wire diameter Φ1.2mm, welding current 270(A), welding voltage 27(V), welding speed 29(cm / min), welding heat input 15(kJ / cm), gas flow 18 (L / min); gas shielded welding adopts multi-layer and multi-pass continuous welding, the interlayer temperature is controlled at 1...

Embodiment 2

[0021] Base material: WNQ690 steel plate, the size of the test plate is 600mm×300mm×26m. The gas shielded welding groove adopts double V-shaped asymmetric groove, the groove angle is 60°, and the blunt edge is 2mm.

[0022] Welding material matching: the mechanical properties of the deposited metal are R el =665MPa, R m =735MPa, A=20%, Z=68%, average impact energy A of deposited metal KV (-40°C) = 182J, combined with WNQ690 steel (26mm+26mm) thick plate using rich argon (20% CO 2 +80% Ar) welding process welding.

[0023] Welding process specification: The chemical composition of the welding wire used is: C: 0.12, Si: 0.80, Mn: 2.0, P≤0.020, S≤0.015, Ni: 1.0, Cr: 0.50, Ti: 0.20, Cu: 0.50, B: 0.0079, Als≤0.02. Welding wire diameter Φ1.2mm, welding current 265(A), welding voltage 27(V), welding speed 29(cm / min), welding heat input 15(kJ / cm), gas flow 18(L / min). Gas-shielded welding adopts multi-layer and multi-pass continuous welding, and the temperature between layers is ...

Embodiment 3

[0026] Base material: WNQ690 steel plate, the size of the test plate is 600mm×300mm×26m. The gas shielded welding groove adopts double V-shaped asymmetric groove, the groove angle is 60°, and the blunt edge is 2mm.

[0027] Welding material matching: the mechanical properties of the deposited metal are R el =665MPa, R m =735MPa, A=20%, Z=68%, average impact energy A of deposited metal KV (-40°C) = 182J, combined with WNQ690 steel (26mm+26mm) thick plate using rich argon (20% CO 2 +80% Ar) welding process welding.

[0028]Welding process specification: The chemical composition of the welding wire used is: C: 0.08, Si: 0.6, Mn: 1.6, P≤0.020, S≤0.015, Ni: 0.8, Cr: 0.3, Ti: 0.10, Cu: 0.40, B: 0.004, Als≤0.02.

[0029] Welding wire diameter Φ1.2mm, welding current 270(A), welding voltage 27(V), welding speed 29(cm / min), welding heat input 15(kJ / cm), gas flow 18(L / min). Gas-shielded welding adopts multi-layer and multi-pass continuous welding, and the temperature between layer...

technical field

[0001] The invention relates to a welding method for steel, in particular to a gas shielded welding process for high-strength steel, which is suitable for welding tensile strength R m ≥690MPa grade low-alloy high-strength steel for marine engineering structures. Background technique

[0002] With the rapid development of my country's metallurgical industry and science and technology, the performance of new steel types and new materials has also been continuously improved. In particular, the development and application of modern controlled rolling and controlled cooling technology and microalloying have greatly improved the strength and toughness of low alloy steel. In particular, modern engineering design and marine engineering machinery manufacturing are increasingly developing in the direction of large-scale, high-parameter, and light-weight. Such as: manufacturing of long-span bridge structures, manufacturing of high-parameter pressure vessels and large-...

Examples

Embodiment 1

[0016] Base material: WNQ690 steel plate, the size of the test plate is 600mm×300mm×26m. The gas shielded welding groove adopts double V-shaped asymmetric groove, the groove angle is 60°, and the blunt edge is 2mm.

[0017] Welding material matching: the mechanical properties of the deposited metal are R el =665MPa, R m =735MPa, A=20%, Z=68%, average impact energy A of deposited metal KV (-40°C) = 182J, combined with WNQ690 steel (26mm+26mm) thick plate using rich argon (20% CO 2 +80% Ar) welding process welding.

[0018] Welding process specification: The chemical composition of the welding wire used is: C: 0.04, Si: 0.40, Mn: 1.40, P≤0.020, S≤0.015, Ni: 0.40, Cr: 0.20, Ti: 0.06, Cu: 0.30, B: 0.002, Als≤0.02, wire diameter Φ1.2mm, welding current 270(A), welding voltage 27(V), welding speed 29(cm / min), welding heat input 15(kJ / cm), gas flow 18 (L / min); gas shielded welding adopts multi-layer and multi-pass continuous welding, the interlayer temperature is controlled at 1...

Embodiment 2

[0021] Base material: WNQ690 steel plate, the size of the test plate is 600mm×300mm×26m. The gas shielded welding groove adopts double V-shaped asymmetric groove, the groove angle is 60°, and the blunt edge is 2mm.

[0022] Welding material matching: the mechanical properties of the deposited metal are R el =665MPa, R m =735MPa, A=20%, Z=68%, average impact energy A of deposited metal KV (-40°C) = 182J, combined with WNQ690 steel (26mm+26mm) thick plate using rich argon (20% CO 2 +80% Ar) welding process welding.

[0023] Welding process specification: The chemical composition of the welding wire used is: C: 0.12, Si: 0.80, Mn: 2.0, P≤0.020, S≤0.015, Ni: 1.0, Cr: 0.50, Ti: 0.20, Cu: 0.50, B: 0.0079, Als≤0.02. Welding wire diameter Φ1.2mm, welding current 265(A), welding voltage 27(V), welding speed 29(cm / min), welding heat input 15(kJ / cm), gas flow 18(L / min). Gas-shielded welding adopts multi-layer and multi-pass continuous welding, and the temperature between layers is ...

Embodiment 3

[0026] Base material: WNQ690 steel plate, the size of the test plate is 600mm×300mm×26m. The gas shielded welding groove adopts double V-shaped asymmetric groove, the groove angle is 60°, and the blunt edge is 2mm.

[0027] Welding material matching: the mechanical properties of the deposited metal are R el =665MPa, R m =735MPa, A=20%, Z=68%, average impact energy A of deposited metal KV (-40°C) = 182J, combined with WNQ690 steel (26mm+26mm) thick plate using rich argon (20% CO 2 +80% Ar) welding process welding.

[0028]Welding process specification: The chemical composition of the welding wire used is: C: 0.08, Si: 0.6, Mn: 1.6, P≤0.020, S≤0.015, Ni: 0.8, Cr: 0.3, Ti: 0.10, Cu: 0.40, B: 0.004, Als≤0.02.

[0029] Welding wire diameter Φ1.2mm, welding current 270(A), welding voltage 27(V), welding speed 29(cm / min), welding heat input 15(kJ / cm), gas flow 18(L / min). Gas-shielded welding adopts multi-layer and multi-pass continuous welding, and the temperature between layer...

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