Nahtloses Stahlrohr, Verfahren zur Herstellung eines Nahtlosen Stahlrohrs, Druckbehälter, Druckbehälter für Wasserstoffgas und Verfahren zur Herstellung eines Druckbehälters oder Druckbehälters für Wasserstoffgas

Details

Veröffentlichungs-Nr.

EP4818348

Anmeldetag

12. Februar 2025

Veröffentlichung

21. August 2025

Rechtsraum

EP

Abstract

The present invention has been made in view of the above circumstances, and an object thereof is to provide a seamless steel pipe having a high martensite fraction, being thick-walled and having high strength, and having excellent quench-crack resistance and delayed-fracture characteristics, which can be extremely suitably used as a member of a pressure vessel and the like. Further, an object thereof is to provide a method for manufacturing a seamless steel pipe, a pressure vessel, a pressure vessel for hydrogen gas, and a method for manufacturing a pressure vessel or a pressure vessel for hydrogen gas. A seamless steel pipe has a specific component composition, satisfying formula (1), a degree of segregation of Mn at an inner surface of the steel pipe of less than 1.50, a metallic microstructure having an area fraction of martensite of 85% or more, and a cross-sectional hardness of 250 HV or more and less than 480 HV. [P] ≤ 0.042 - 0.002[C] - 0.024[Mn] - 0.001[Mo] - 0.001[Cr] - 0.002[Ni] ··· (1) <img class="EMIRef" id="6cfe2908-1fb6-497a-a6e5-a33faf32ca5e-ia01" /> (where [element] represents a content (mass%) of the element described in each set of brackets).

Anmelder

Firma

JFE Steel Corporation

Land

🇯🇵 Japan