Thick-wall high-strength steel double-sided submerged arc welding method for dynamic load occasion

Abstract

The invention relates to a thick-wall high-strength steel double-sided submerged-arc welding method for dynamic load occasions, which comprises the following steps: the same high-strength steel plates are combined and butted, the wall thickness T of each steel plate is greater than or equal to 13mm, and the yield strength of each steel plate is less than or equal to 690MPa; an X-shaped groove is adopted, the angle of an upper groove is 50-100 degrees, the angle of a lower groove is 60-110 degrees, the depth ratio of the upper groove to the lower groove is 1.1-1.5, and the assembly gap is 0-0.5 mm; the height R of the truncated edge is 4-10mm and is less than or equal to T / 3; carrying out one-time single-pass double-sided submerged arc welding at a ship-shaped position by adopting flat welding; the welding heat input, the groove angle and the groove depth meet certain conditions, the welding heat input, the welding current, the welding voltage, the welding speed and the welding wire diameter meet certain conditions, and the welding current is related to the welding wire diameter and the truncated edge height. By means of the method, the one-time single-pass double-face submerged-arc welding forming weld joint which is good in overall quality, uniform in weld pass spreading and smooth in weld toe transition can be obtained, the fatigue performance of a welded joint can be improved, and the service life can be prolonged.

Description

technical field [0001] The invention relates to low-alloy high-strength steel welding technology, in particular to a double-sided submerged arc welding method for thick-walled high-strength steel used in dynamic load situations. Background technique [0002] Low-alloy high-strength steel is widely used in many industrial fields because of its good strength, toughness and weldability, especially in construction machinery, marine structures, rail vehicles, heavy energy equipment, etc. The welded structures made of low-alloy high-strength steel are mostly used in these Field of alternating load occasions. Welding is the key technology and main process of on-site manufacturing. Due to the unbalanced heating and cooling of the welding process itself and the unbalanced solid-state phase transition caused by it, the welded joint often becomes the weak link of the entire structure. Various structural failures are also often related to the weakening of the performance of welded join...

AI Technical Summary

Problems solved by technology

However, this type of welding material needs high Cr, Ni and ultra-low carbon alloy components, the cost is very high, and the prospect of batch application is still unclear

In addition, after the alloy content increases, the spreadability of the welding bead on the cover surface will become poor, which is not conducive to the uniform and smooth transition of the weld toe, but will cause a decrease in fatigue performance

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