Marine high-strength steel plate double-wire submerged-arc welding process

A high-strength steel plate and welding process technology, applied in the field of steel material welding, can solve the problems of container ship hull structure fracture, phase transformation cooling rate slowing down, high temperature residence time prolonging, etc., to achieve excellent joint comprehensive performance, reduce heat ratio, welding The effect of thermal cycling improvement

Inactive Publication Date: 2019-06-07
INST OF RES OF IRON & STEEL JIANGSU PROVINCE +2
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] However, the heat input of conventional twin-wire submerged arc welding is large. After the large-scale, high-strength steel plate is welded with high heat input, the high-temperature residence time is prolonged, the phase change cooling rate is slowed down, and the weld metal structure appears coarse grains. The austenite grains in the welding coarse-grained heat-affected zone (CGHAZ) grow rapidly, and it is easy to form coarse bainite and island martensite, which seriously deteriorates the toughness of CGHAZ. Some refractory particles such as nitrides and carbides cannot be precipitated in time during the cooling process after dissolution, resulting in a sharp deterioration in the performance of welded joints. The above situation is often the root cause of fractures in the hull structure of container ships and catastrophic accidents
Therefore, conventional twin-wire submerged arc welding has certain limitations in service conditions with relatively high toughness requirements.

Method used

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  • Marine high-strength steel plate double-wire submerged-arc welding process

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Effect test

Embodiment 1

[0021] (1) EH47 high-strength anti-crack steel plate is used, which is combined with EH47 high-strength anti-crack steel plate of the same plate thickness, and the plate thickness combination is 50mm+50mm. The size of the test plate is 1000mm×400mm×50mm; the carbon content of the steel plate is less than 0.10%, and the cold crack sensitivity index Pcm≤0.21%;

[0022] (2) The groove adopts X-shaped groove, as attached figure 1 As shown, the up-groove angle α is 50°, the down-groove angle β is 60°, and the up-groove depth h 1 20mm, the blunt edge of the groove l 1 3-4mm, groove gap l 2 3mm;

[0023] (3) The front wire adopts DC reverse connection, the wire diameter is Ф2.4mm, and is perpendicular to the surface of the test plate; the rear wire adopts AC, the wire diameter is Ф4.0mm, the angle with the front wire is 10°, and the welding wire spacing is 25mm;

[0024] (4) The chemical composition and weight percentage of the submerged arc welding wire used are: C: 0.05-0.10%, ...

Embodiment 2

[0028] (1) EH47 high-strength anti-crack steel plate is used, which is combined with EH47 high-strength anti-crack steel plate of the same plate thickness, and the plate thickness combination is 100mm+100mm. The size of the test plate is 1000mm×400mm×100mm; the carbon content of the steel plate is less than 0.10%, and the cold crack sensitivity index Pcm≤0.21%.

[0029] (2) The groove adopts X-shaped groove, as attached figure 1 As shown, the up-groove angle α is 60°, the down-groove angle β is 70°, and the up-groove depth h 1 60mm, blunt edge l 1 4-6mm, groove clearance l 2 is 0mm;

[0030] (3) The double-wire submerged arc welding process is adopted, the front wire adopts DC reverse connection, the wire diameter is Ф2.4mm, and is perpendicular to the surface of the test plate; the rear wire adopts AC, the wire diameter is Ф4.0mm, and the included angle with the front wire is 15°, welding wire spacing is 35mm;

[0031] (4) Submerged arc welding wire and flux used. The c...

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Abstract

The invention discloses a marine high-strength steel plate double-wire submerged-arc welding process. An EH47 high-strength anti-cracking steel plate is selected, the thickness of the EH47 high-strength anti-cracking steel plate is 50-100 mm, a double-wire submerged-arc welding process with a front wire as a fine welding wire and a rear wire as a thick welding wire is adopted, and high-efficiencywelding of low heat input is realized. According to the marine high-strength steel plate double-wire submerged-arc welding process, the design requirements of the EH47 high-strength anti-crack steel plate welding joint high standard are met while the high efficiency of the double-wire submerged arc welding is guaranteed, so that the optimization of the welding quality and the efficiency is realized. The marine high-strength steel plate double-wire submerged-arc welding process is high in practicability, simple and convenient in welding operation, efficient and energy-saving, and is suitable for building and popularization and application of container ships.

Description

technical field [0001] The invention belongs to the technical field of iron and steel material welding, and in particular relates to a double-wire submerged arc welding process for high-strength steel plates for ships. Background technique [0002] In recent years, in order to improve transportation efficiency, major shipping companies and shipowners tend to choose high-strength thick steel plates with good performance when choosing marine steel plates. At present, EH47 high-strength crack-arrest steel plates have high strength, excellent low-temperature toughness and crack arrest performance. It has been applied to the upper deck area structure of container ships, especially the hatch coaming structure, and its thickness can reach 50mm-100mm. EH47 anti-crack steel plate is a high-tech product in ship steel. Generally, it is required that the tensile strength of the welded joint of EH47 high-strength anti-crack steel plate should be equivalent to that of the base metal, and ...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): B23K9/18B23K9/235
Inventor 李丽陆春洁田猛唐家龙
Owner INST OF RES OF IRON & STEEL JIANGSU PROVINCE
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