Grade 550mpa high-temperature resistant pipeline steel and method of manufacturing same

Abstract

Disclosed is a Grade 550 MPa high temperature-resistant pipeline steel, the chemical elements, in mass percentage, being: 0.061%≦C≦0.120%, 1.70%≦Mn≦2.20%, 0.15%≦Mo≦0.39%, 0.15%≦Cu≦0.30%, 0.15%≦Ni≦0.50%, 0.035%≦Nb≦0.080%, 0.005%≦V≦0.054%, 0.005%≦Ti≦0.030%, 0.015%≦Al≦0.040%, 0.005%≦Ca≦0.035%, and the balance being Fe and unavoidable impurities. Also disclosed is a manufacturing method of the Grade 550 MPa high temperature-resistant pipeline steel, comprising the steps of: smelting, casting, slab heating, rough rolling, finish rolling, controlled cooling, and air cooling to room temperature. The pipeline steel has an excellent mechanical property under a high temperature.

Dependencies are inferred from the claim text.