A preparation method of plastic-lined steel pipe adopting welding connection

Abstract

The present invention discloses a method for manufacturing lining plastic pipe by using welded connection. The method comprises the following steps: (1) stripping one section of the plastic anticorrosive coating of the lining plastic pipe port that has been subjected to lining plastic recombination, wherein the lining plastic pipe port being stripped the plastic anticorrosive coating is the connection end of the external steel pipe; (2) lining the inner wall of the connection end that is not lined with the plastic anticorrosive coating with a hot melt adhesive, wherein the hot melt adhesive is adhered to the inner wall of the connection end to form a hot melt adhesive layer; (3) inserting a stainless steel pipe into the external steel pipe from the connection end of the external steel pipe, wherein the outer wall of the stainless steel pipe is adhered with the hot melt adhesive layer; and (4) welding the outer wall of the stainless steel pipe and the port of the external steel pipe. The lining plastic pipe manufactured by this method can efficiently solve the problem of electrochemical corrosion after welding the dissimilar steel, solve the structural problem that the steel-plastic pipe cannot directly adopt welded connection, and expands the application of the stainless steel in steel-plastic pipe manufacture.

Description

technical field [0001] The invention relates to a method for preparing plastic-lined steel pipes, in particular to a method for preparing plastic-lined steel pipes connected by welding. Background technique [0002] With the continuous expansion of the application fields of plastic-lined steel pipes, people put forward higher requirements for the connection of plastic-lined steel pipes. The plastic-lined steel pipes currently available in the market basically adopt the traditional three connection methods of thread, groove or flange; , it is required to use welding connection, and it is also required that the anti-corrosion layer inside the pipeline cannot be damaged. The traditional connection method cannot meet the above requirements; in the above fields, there are serious problems in the existing connection methods of ordinary plastic-lined steel pipes: inconvenient. If the welding connection is used directly, the inner plastic pipe will be damaged due to high temperatu...

AI Technical Summary

Problems solved by technology

[0004] In order to overcome the above-mentioned defects in the prior art, the present invention provides a method for preparing plastic-lined steel pipes connected by welding. This preparation method can not only effectively solve the problem of electrochemical corrosion of dissimilar steels after welding, but also solve the Structural problems that cannot be directly connected by welding expand the application of stainless steel in the manufacture of steel-plastic pipes

Images