Welding Technology of Hydrogen Sulfide Resistant Pipeline

Abstract

The invention discloses a welding process of a hydrogen sulfide-resistant pipeline, which comprises the following steps: Step 1. Cutting the end faces of the welding ends of the two pipelines to be welded, so that the welded joint forms an annular V-shaped groove, and the groove The angle is 60±2.5°, and the blunt edge is 0~0.5mm; step 2, set up the two pipes to be welded on the positioning mechanism, and connect the welding ends of the two pipes horizontally through the connector, and the weld width is 3.0 ~4.5mm; step 3, preheat the welded joint of the pipeline for 1 hour, the preheating temperature is 100-150°C; start the inflation mechanism, fill the space between the two sealing blocks with argon, and then weld the weld seam. The invention can precisely butt two pipelines, ensure that the axes of the two pipelines are on the same horizontal line, and have high adjustability of the distance between weld seams, thereby ensuring the crack resistance of weld seam welding.

Description

technical field [0001] The invention relates to the technical field of pipeline welding. More specifically, the present invention relates to a welding process for hydrogen sulfide resistant pipelines. Background technique [0002] In my country's petrochemical production, some high-sulfur natural gas, such as hydrogen sulfide natural gas, is often encountered. Due to the strong corrosiveness of hydrogen sulfide gas, electrochemical reactions may occur during contact with equipment, and hydrogen atoms are precipitated at the cathode, but due to the existence of hydrogen sulfide itself, hydrogen atoms are often prevented from synthesizing hydrogen molecules, so that The hydrogen atoms cannot be discharged, but can only enter the equipment pipeline, thus forming sulfide stress cracking and hydrogen-induced cracking. [0003] Therefore, certain anti-hydrogen sulfide measures must be taken in petrochemical production, and the main method is to install corresponding anti-sulfur ...

AI Technical Summary

Problems solved by technology

However, in the specific installation process, if the welding is improper, the anti-sulfur effect will not meet the ideal requirements, so it is necessary to pay attention to the welding of anti-sulfur pipelines

[0004] The pipes are cracked due to stress corrosion, especially the welds are most susceptible to corrosion, and the first to break is the fusion line. Before welding, the joints of the two pipes must be connected to ensure that the axes of the two pipes are at the same Horizontal line, in the prior art, the horizontal position of the two axes is usually adjusted artificially based on experience when the two pipes are close to each other, the controllability is poor, and the operation is difficult; in addition, the gasket inside the pipe is difficult to install , poor sealing effect, etc.

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