A bainite seamless steel pipe and manufacturing method therefor

Abstract

The present invention provides a bainite seamless steel pipe and a manufacturing method therefor. In addition to Fe and inevitable impurities, the bainite seamless steel pipe further comprises the following chemical elements in percentage by mass: C: 0.16-0.18%, Si: 0.56-1%, Mn: 1.8-2.05%, Cr: 0.85-1.25%, Al: 0.015-0.04%, B: 0.001-0.005%, 0<N≤0.006%, wherein Al/N≥3. The bainite seamless steel pipe of the present invention can obtain good strength-toughness matching in a rolled state or a single tempered state without the need for quenching and tempering heat treatment.

Dependencies are inferred from the claim text.