Welding method for cooperatively improving pitting corrosion resistance and intergranular corrosion resistance of 316L process pipeline welding heat affected zone

Abstract

The invention provides a welding method for cooperatively improving pitting corrosion resistance and intergranular corrosion resistance of a 316L process pipeline welding heat affected zone, and relates to the technical field of welding. The invention provides an inert gas tungsten electrode argon arc welding method for a 316L process pipeline, namely a welding process for reasonably controlling inert gas tungsten electrode argon arc welding heat input for the 316L process pipeline. According to the welding method, the proper welding line heat can be rapidly selected, a welding heat affected zone with a large size is obtained through the thermal simulation technology, and tissue and performance tests can be conveniently carried out; strict and reasonable control over parameters of all stages is achieved, the process is standard, the time cost and the economic cost are reduced, and therefore, development of the welding process of the 316L process pipeline under marine environment service is comprehensively improved; and under the condition that the welding quality is guaranteed, the welding operation steps are simplified, and the welding work efficiency is improved.

Description

technical field [0001] The invention belongs to the field of welding technology, and in particular relates to a welding method for synergistically improving resistance to pitting corrosion and intergranular corrosion in a welding heat-affected zone of a 316L process pipeline. Background technique [0002] AISI 316L stainless steel not only contains an appropriate amount of chromium, nickel, but also about 2% molybdenum, which is conducive to obtaining a single-phase austenite structure, and has a higher electrode potential than AISI 304, so this type of stainless steel has good plasticity and toughness , corrosion resistance, weldability and processability. The overall cost of use in corrosive environments is low. 316L is widely used in chemical industry, coastal, food, biomedicine, petrochemical and other fields, and the global rate is still increasing at a rate of 3%-5% per year. Welded structures have good airtightness and economy and have become the most common form of ...

AI Technical Summary

Problems solved by technology

Intergranular corrosion refers to the corrosion that occurs in a region that is smaller than the grain size, including the grain boundary. Generally, it is invisible to the naked eye when corrosion damage occurs, but when it is stressed, it will break along the grain boundary and almost lose its strength. Brings huge safety hazards to welded structures

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