Global Patent Index - EP 4282991 A1

EP 4282991 A1 20231129 - RAIL AND METHOD FOR MANUFACTURING SAME

Title (en)

RAIL AND METHOD FOR MANUFACTURING SAME

Title (de)

SCHIENE UND VERFAHREN ZUR HERSTELLUNG DAVON

Title (fr)

RAIL ET SON PROCÉDÉ DE FABRICATION

Publication

EP 4282991 A1 20231129 (EN)

Application

EP 22779522 A 20220204

Priority

  • JP 2022004530 W 20220204
  • JP 2021060122 A 20210331

Abstract (en)

An object is to provide a method for manufacturing a high-hardness and high-quality rail through a simple cooling process even in the presence of temperature variations in the longitudinal direction of the rail before the start of cooling.A rail manufacturing method includes a step of accelerated cooling a rail having a temperature equal to or higher than an austenite region temperature. In the rail manufacturing method, austenite represents a portion of a region from a cooled surface of a rail head to a depth of 5 mm at the end of accelerated cooling, and the temperature of a rail head surface at the completion of heat recuperation after the end of accelerated cooling is in a pearlite transformation temperature range.

IPC 8 full level

C21D 8/00 (2006.01); C21D 9/04 (2006.01); C22C 38/00 (2006.01); C22C 38/60 (2006.01)

CPC (source: EP)

C21D 1/19 (2013.01); C21D 6/002 (2013.01); C21D 8/005 (2013.01); C21D 9/04 (2013.01); C21D 2211/002 (2013.01); C21D 2211/009 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/20 (2013.01); C22C 38/22 (2013.01); C22C 38/24 (2013.01); C22C 38/26 (2013.01); C22C 38/28 (2013.01); C22C 38/40 (2013.01); C22C 38/60 (2013.01)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

Designated extension state (EPC)

BA ME

Designated validation state (EPC)

KH MA MD TN

DOCDB simple family (publication)

EP 4282991 A1 20231129; EP 4282991 A4 20240703; JP 7405250 B2 20231226; JP WO2022209293 A1 20221006; WO 2022209293 A1 20221006

DOCDB simple family (application)

EP 22779522 A 20220204; JP 2022004530 W 20220204; JP 2022527100 A 20220204