Pressure accumulator steel pipe, pressure accumulator steel pipe manufacturing method, and composite container pressure accumulator liner

摘要

A steel pipe or tube for pressure vessels having excellent quench crack resistance is provided. The steel pipe or tube for pressure vessels comprises: a specific chemical composition; and a metallic microstructure in which an average grain size of prior austenite grains is 500 µm or less, and an area fraction of microstructures other than ferrite is 50 % or more.