Method for manufacturing straight-line thermometal composite welded pipe

Abstract

Disclosed is a method for manufacturing a straight-line thermometal composite welded pipe. The method comprises the steps that a thermometal hot rolling composite board produced by the explosion or hot rolling process is taken as raw materials, longitudinal edge pre-bending and stamping are carried out on the materials, stamping is based on the three-point bending basic principle, forming is achieved according to the sequence of J shape -> C shape -> O shape, and the product is manufactured through welding. According to the method for manufacturing the straight-line thermometal composite welded pipe, the forming mode is adopted to manufacture the straight-line thermometal composite welded pipe. Therefore, the method is suitable for industrialized mass production. In addition, due to the fact that the welding line is the straight line, therefore, compared with the length of a spiral welding line, length of the straight welding line is reduced by at least 30 percent, few welding materials are consumed, machining time is short, and the probability that a quality problem happens to the welding line is relatively small. In addition, due to the fact that in the use process, the resistance of the straight line in the pipe on conveyed media is small, the conveying speed of the liquid can be improved. Foreign matter is not easily hung on or happens to the welding line, and therefore the corrosive medium deposition cannot happen.

Description

technical field [0001] The invention belongs to the technical field of manufacturing composite welded pipes, in particular to a method for manufacturing straight seam bimetallic composite welded pipes. technical background [0002] In petroleum, natural gas, chemical industry and other industries, because the pipeline transportation medium is rich in H 2 S, CO 2 , Cl ions and other corrosive media. Therefore, during the use of the pipeline, these corrosive media will cause severe uniform corrosion, pitting corrosion, sulfide stress corrosion cracking and hydrogen-induced cracking in the pipeline, which will cause failure and accidents in the pipeline. Therefore, the use of Corrosion-resistant bimetallic composite pipe is one of the safest and most economical choices, and it is the development direction of corrosion-resistant transportation pipes. [0003] At present, the commonly used bimetal composite welded pipe uses carbon steel plate as the base material and stainless ...

AI Technical Summary

Problems solved by technology

The advantage of this bimetallic composite welded pipe is that the shear strength is as high as 210Mpa, and it can transport high-temperature media below 400°, but the disadvantage is that its weld seam is spiral, so the weld seam is relatively long, so the welding material consumption is large and the processing time is high. Long, and the probability of weld quality problems is high

In addition, as mentioned above, since the weld seam is in a spiral shape, the spiral weld seam located in the pipe will form a large resistance to the conveyed medium during use, resulting in a low liquid conveying rate and easy hanging at the weld seam Foreign matter, which results in problems with deposits of corrosive media there

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