STEEL PIPE OR TUBE FOR PRESSURE VESSELS, METHOD OF PRODUCING STEEL PIPE OR TUBE FOR PRESSURE VESSELS, AND COMPOSITE PRESSURE VESSEL 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.