Field welding repair method particularly suitable for bead weld layer defects on low alloy and carbon steel

Abstract

The invention relates to a field welding repair method particularly suitable for bead weld layer defects on low alloy and carbon steel. The field welding repair method includes the steps that firstly, the defects are eliminated in a polished mode; secondly, welding materials having the same quality with bead weld layer materials are used for conducting welding repair on the defects, and a repair bead is obtained; thirdly, after the welding repair in the second step is completed, welding of a tempering bead is immediately conducted, and welding materials having the same or similar material mark with the bead weld layer materials are selected in welding of the tempering bead; fourthly, after welding of the tempering bead is completed and the temperature is reduced to the room temperature, excess weld metal of the tempering bead and excess weld metal of the repair bead are removed in a polished mode. According to the field welding repair method, the rigidity of the area, close to a fusion line area, of a base material of a base layer can be reduced while heat treatment is not conducted, the good tissue of the base material is ensured, and field construction is well facilitated.

Description

technical field [0001] The invention belongs to the technical field of welding repair, and in particular relates to an on-site welding repair method for welding layer defects on low-alloy steel, carbon steel and the like. Background technique [0002] The surfacing layer of stainless steel and nickel-based alloy on low-alloy steel and carbon steel is a commonly used structure in thermal power, nuclear power and petrochemical industries. The surfacing layer is usually 3~10mm thick and is generally in direct contact with the operating medium, thereby improving the structure. Corrosion resistance. During the operation, due to the influence of the operating environment or external factors, the surfacing layer may have defects, which need to be repaired by welding on site. [0003] The method usually used on site is to repair the defects by welding with welding materials of the same quality as the surfacing layer material after grinding. Due to the limitation of site conditions ...

AI Technical Summary

Problems solved by technology

With this scheme, the welding process is likely to have adverse effects on the underlying base metal (low alloy steel or carbon steel), such as the generation of hardened structures at the joint surface, which reduces the hardness of the joint surface. Toughness, thereby reducing the ability of the surfacing layer to resist peeling, and it is also easy to generate cracks at the joint surface, thus affecting the safety of the structure

Images