Method for manufacturing delivery steel pipe serving acid environment

Abstract

The invention discloses a method for manufacturing a delivery steel pipe serving an acid environment. The steel pipe comprises the following chemical components of raw materials in percentage by weight: less than or equal to 0.1 percent of C, less than or equal to 1.6 percent of Mn, less than or equal to 0.02 percent of P, less than or equal to 0.002 percent of S, less than or equal to 0.15 percent of Nb, V and Ti, less than or equal to 0.22 percent of Pcm, more than or equal to 1.5 percent of Ca/S and the balance of Fe. High frequency induction welding is adopted in welding of the steel pipe; the welding quality is improved in the welding process by increasing the welding extrusion quantity, controlling the open angle of seams and increasing welding protective gas; and on-line quenching and on-line tempering are performed in heat treatment of the seams by adopting six intermediate frequency heat treatment machines. By selection of raw material components and metallographic structures, completeness of a welding mechanism and improvement of the heat treatment process, the steel pipe has hydrogen induced cracking resistance and sulfide stress corrosion resistance and has high strength and high pressure resistance, the cost can be reduced, and the use of the steel pipe under the acid serving condition can be met.

Description

technical field [0001] The invention relates to a method for manufacturing a steel pipe in the metallurgical industry, in particular to a method for manufacturing a steel pipe for transportation used in an acidic environment. Background technique [0002] At present, the delivery steel pipes used in acidic environments usually adopt seamless steel pipes. For example, the Chinese invention patent with the publication number CN101146924 "Steel for oil well pipes with excellent resistance to sulfide stress cracking and a method for manufacturing seamless steel pipes for oil wells" proposed A seamless steel pipe for oil wells that can be used in acidic environments. The seamless steel pipe uses higher carbon content and alloying elements to improve corrosion resistance, but has uneven wall thickness, low geometric dimension accuracy, low impact toughness and production costs. advanced defects. [0003] The high-frequency welded (HFW) pipeline steel pipe serving in acidic enviro...

AI Technical Summary

Problems solved by technology

[0006] What the present invention aims to solve is the poor corrosion resistance of the steel pipe caused by the serious band structure in the center of the plate during the raw material rolling process and the poor uniformity of the steel pipe structure caused by the residual stress and poor heat treatment state in the pipe making process. technical problem, to provide a product that

Images