STEEL PIPE FOR OIL WELL HAVING EXCELLENT COLLAPSE STRENGTH, AND TESTING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To stably provide steel pipes for oil well having excellent collapse strength. SOLUTION: In the steel pipes for oil well having excellent collapse strength, yield stress YS is >=552 MPa (80 ksi) and L-direction absorption energy E (J) at 0 deg.C satisfies inequality E>=-0.4169×YS+480. This method is for judging whether or not the manufactured steel pipes conform to the steel pipes for oil well having excellent collapse strength on the basis of the results of tensile tests and Charpy impact tests on the steel pipes.