Widerstandsgeschweisstes Stahlrohr und Verfahren zur Herstellung davon

Details

Veröffentlichungs-Nr.

EP4768617

Anmeldetag

3. Oktober 2024

Veröffentlichung

24. April 2025

Rechtsraum

EP

Abstract

Objects of the present invention are to provide an electric resistance welded steel pipe having excellent weld quality and to provide a method for manufacturing the same. An electric resistance welded steel pipe including a base metal and an electric resistance weld, the base metal having a chemical composition containing, in mass%, C: 0.10 to 0.50%, Si: 0.15 to 0.35%, Mn: 0.60 to 0.90%, Al: 0.001 to 0.1%, P: 0.03% or less, S: 0.03% or less, Cr: 0.90 to 1.20%, Mo: 0.15 to 0.30%, and Ni: 0.25% or less, with the balance being Fe and unavoidable impurities, wherein the chemical composition has a Mn/(Si+Cr) of 0.52 or greater and 0.85 or less, and, in a flattening test of the electric resistance welded steel pipe, inequality (1), shown below, is satisfied: h / D ≤ 0.5 <img class="EMIRef" id="2f111e84-aa0f-49de-8f28-82cc50609fbc-ia01" /> where h is a flattening crack height (mm), at which an initial crack is observed in the electric resistance weld, and D is an outside diameter (mm) of the steel pipe.

Anmelder

Firma

JFE Steel Corporation

Land

🇯🇵 Japan