Process for manufacturing cold-rolled/cold-drawn precise welded steel pipe

Abstract

The invention discloses a process for manufacturing a cold-rolled/cold-drawn precise welded steel pipe. The process comprises the following steps of: 1) feeding; 2) slitting; 3) processing the welded pipe; 4) deoiling and degreasing the finished product welded pipe at high temperature and washing at high temperature; 5) performing non-oxidation annealing on the welded pipe which is deoiled and degreased at high temperature; 6) pinching the head of the annealed welded pipe, and dipping the annealed welded pipe in rolling/drawing lubricating oil; 7) performing cold rolling/cold drawing on the welded pipe by using a cold rolling/cold drawing mill; and 8) comprehensively inspecting, packaging and putting in storage. By a cold rolling or cold drawing process, compact hardened films are formed on inner and outer surfaces of a pipe body through extrusion, the tensile strength, the surface hardness and the wear resistance of the steel pipe are improved obviously, and the application range of the steel pipe is widened. Meanwhile, by applying the non-oxidation annealing process, the processes of scouring, phosphorization and water and oil removing are eliminated, the process is shortened, the material and energy consumption in the technological process is reduced, the working efficiency is improved, and cost is reduced.

Description

technical field [0001] The invention relates to a cold-rolled / cold-drawn precision welded steel pipe manufacturing process. Background technique [0002] With the rapid development of continuous rolling production of high-quality strip steel and the advancement of welding and inspection technology, the quality of welds has been continuously improved, and the varieties and specifications of welded steel pipes have increased day by day, and seamless steel pipes have been replaced in more and more fields. Welded steel pipes have lower cost and higher production efficiency than seamless steel pipes. As a precision-grade welded steel pipe, it has high performance in terms of wear resistance, surface hardness, and tensile strength, and can even completely replace seamless steel pipes. However, the current manufacturing process of precision welded steel pipes still has deficiencies in the selection of process parameters and the adjustment of process processes, especially in terms ...

AI Technical Summary

Problems solved by technology

However, the current manufacturing process of precision welded steel pipes still has deficiencies in the selection of process parameters and the adjustment of process processes, especially in terms of heat treatment. The ordinary annealing process is used to easily produce scale on the surface of the