EP 1795274 B1 20120215 - METHOD FOR HOT WORKING OF Cr-CONTAINING STEEL
Title (en)
METHOD FOR HOT WORKING OF Cr-CONTAINING STEEL
Title (de)
VERFAHREN ZUM WARMVERFORMEN VON CR-HALTIGEM STAHL
Title (fr)
PROCÉDÉ DE FAÇONNAGE À CHAUD D' UN ACIER CONTENANT DU Cr
Publication
Application
Priority
JP 2004010302 W 20040720
Abstract (en)
[origin: EP1795274A1] The hot-working method of Cr-containing steels by the invention, is characterized in that : a newly created surface in a Cr-containing steel is held in a steam atmosphere to form an oxide scale including FeO; and then, next processing step in hot-working is applied, whereas, more specifically, in producing seamless steel tubes, moisture is supplied into the inside of the hollow shell made by the piercing-rolling process to hold the newly created inside surface of the shell in the steam atmosphere, so that the oxide scale including FeO is formed on the shell inside surface: and then, next elongation-rolling process is applied. As such, the above entails just a concise operational procedure and simple device configuration, enabling to decrease the surface defects generated in hot-working and to extend the tool life dramatically. Hence, this invention can greatly contribute to efficiently manufacture Cr-containing steels, 5-18% Cr, which are in growing demand.
IPC 8 full level
B21B 17/02 (2006.01); B21B 19/04 (2006.01); B21B 23/00 (2006.01); C21D 8/10 (2006.01); C23C 8/18 (2006.01)
CPC (source: EP)
B21B 23/00 (2013.01); C21D 8/105 (2013.01); C23C 8/18 (2013.01); C23C 8/80 (2013.01); B21B 3/02 (2013.01)
Citation (examination)
JP S6415356 A 19890119 - KOBE STEEL LTD
Designated contracting state (EPC)
DE FR IT
DOCDB simple family (publication)
EP 1795274 A1 20070613; EP 1795274 A4 20090318; EP 1795274 B1 20120215; CN 100493746 C 20090603; CN 1993189 A 20070704; WO 2006008804 A1 20060126
DOCDB simple family (application)
EP 04770813 A 20040720; CN 200480043635 A 20040720; JP 2004010302 W 20040720