Method for manufacturing inner covered stainless steel compound steel pipe

Abstract

The invention discloses a method for manufacturing an inner covered stainless steel compound steel pipe which has good combination quality, simple working process, lower cost as well as favorable tissue and property of a stainless steel layer and a carbon steel layer. The method for manufacturing the inner covered stainless steel compound steel pipe comprises the following steps: cleaning a stainless steel thin-wall welded pipe, a carbon steel pipe and the surface of a pure copper foil after solution treatment; wrapping the pure copper foil outside the stainless steel thin-wall welded pipe, and then placing the pure copper foil and the stainless steel thin-wall welded pipe into the carbon steel pipe together; mutually sleeving an inner pipe, the pure copper foil and an outer pipe; carrying out cold drawing so that the inner pipe, the pure copper foil and the outer pipe are closely attached so as to form an interference-fit compound pipe blank; placing the interference-fit compound pipe blank into a diffusion annealing furnace filled with protective gases, heating at the temperature of 900-950 DEG C, preserving the temperature for 10-60 minutes, and cooling the compound pipe blank to normal temperature at the speed of 100-200 DEG C / minute for diffusion bonding after the compound pipe blank is taken out of the diffusion annealing furnace.

Description

Technical field: [0001] The invention relates to a manufacturing method of a bimetallic composite pipe for industrial and civil use, in particular to an inner clad stainless steel composite pipe with good bonding quality, simple process, low cost, good structure and performance of the stainless steel layer and the carbon steel layer at the same time. Manufacturing method of steel pipe. Background technique: [0002] The stainless steel clad steel pipe covered with stainless steel inside the carbon steel pipe has both the excellent corrosion resistance of stainless steel and the high strength of carbon steel. Advantages such as saving resources. The existing stainless steel clad steel pipes can be divided into two types according to the bonding conditions: mechanical bonding and metallurgical bonding. Mechanically bonded stainless steel clad steel pipe, in the process of bending, torsion, etc., or when the temperature, pressure, and load change, the phenomenon of inner pipe...

AI Technical Summary

Problems solved by technology

However, nickel-based solder is used in the method, which not only has high raw material cost, but also increases the energy consumption due to the high brazing temperature, which further increases the manufacturing cost of the product, resulting in a coarse structure of the base pipe and a decline in performance; the solder is coated by a coating method. On the outer surface of the liner, there will inevitably be environmental pollution problems; after induction heating, water is sprayed for rapid cooling, which greatly damages the plasticity and toughness of the base pipe