Patent ID: 9034125
Filing Date: 2015-05-19
Classification: B21B,C22C,C22F

Abstract:
1. A method for manufacturing an Ni base alloy pipe stock, comprising piercing and rolling a billet, by use of a Mannesmann piercing and rolling mill, which satisfies the chemical compositions consisting of, by mass %, C: not more than 0.04%, Si: not more than 0.50%, Mn: 0.01 to 6.0%, P: not more than 0.03%, S: not more than 0.01%, Cr: 15 to 30%, Ni: more than 45% to not more than 60%, Mo: 0 to 18%, W: 0 to 36%, with Mo (%)+0.5W (%): more than 1.5% to not more than 18%, Cu: 0.01 to 1.5%, Al: not more than 0.10% and N: 0.005 to 0.20%, and the balance being substantially Fe, with values of T GBm , P sr and P σ represented by the following equations (1) to (3) being not more than 1300, not more than 200 and not less than 0, respectively, and moreover being subjected to piercing and rolling by a Mannesmann piercing and rolling mill: wherein each element symbol in the equations (1) to (3) represents the content by mass % of the element concerned.