公开(公告)号：EP2980230A4

公开(公告)日：2016-04-13

申请号：EP14773268

申请日：2014-03-25

申请人： JFE STEEL CORP

发明人： OKUSHIRO KENJI ,  FUKUDA HIROYUKI ,  KIJIMA HIDEO ,  YAMAGUCHI MORIYASU

IPC分类号： C21D9/04 ,  B21B1/085 ,  B21B45/02 ,  C21D1/18 ,  C21D8/00 ,  C22C38/00 ,  C22C38/50

CPC分类号： C21D9/04 ,  B21B1/085 ,  B21B45/02 ,  B21B2045/0221 ,  C21D1/18 ,  C21D1/56 ,  C21D1/62 ,  C21D1/667 ,  C21D6/00 ,  C21D2211/009 ,  C22C38/00 ,  C22C38/50

摘要： A rail-manufacturing method according to the present invention performs forced cooling on at least a head of a hot rail hot-rolled at or heated to the austenite region temperature or higher. The forced cooling is performed for 10 seconds from start of the forced cooling so that the cooling rate at the head surface becomes 1°C/s or higher to 20°C/s or lower, the forced cooling is performed after a lapse of 10 seconds from the start of the forced cooling until heat generation during transformation begins in the head surface so that the cooling rate at the head surface becomes 1°C/s or higher to 5°C/s or lower, the forced cooling is performed during transformation from beginning to end of the heat generation during transformation so that the cooling rate at the head surface becomes lower than 1°C/s or the temperature-rising rate becomes 5°C/s or lower, and the forced cooling is performed after the end of the heat generation during transformation until the rail-head surface temperature becomes 450°C or lower so that the cooling rate at the head surface becomes 1°C/s or higher to 20°C/s or lower.

公开(公告)号：EP3199255A4

公开(公告)日：2017-11-01

申请号：EP15845139

申请日：2015-09-10

申请人： JFE STEEL CORP

发明人： OKUSHIRO KENJI ,  KIJIMA HIDEO ,  FUKUDA HIROYUKI ,  YAMAGUCHI MORIYASU

IPC分类号： B21B1/085 ,  C21D8/00 ,  C21D9/04 ,  C22C38/00 ,  C22C38/60

CPC分类号： C21D9/04 ,  B21B1/085 ,  C21D8/00 ,  C21D8/005 ,  C22C38/00 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/24 ,  C22C38/26 ,  C22C38/42 ,  C22C38/44 ,  C22C38/50 ,  C22C38/60

摘要： To provide a method and an apparatus for manufacturing a rail having high ductility in both a head portion and a foot portion. A heated steel rail material is hot-rolled, the temperature is adjusted by cooling the hot-rolled steel rail material, the steel rail material subjected to the temperature adjustment is processed into a rail shape by means of temperature-adjusted rolling at an area reduction ratio of 20% or more, and, in adjusting the temperature of the steel rail material, the surface portions of the steel rail material corresponding to a head portion and a foot portion of the rail shape so that the temperatures of the surface portions reach 500°C or more and 1,000C or less.

公开(公告)号：EP2980231A4

公开(公告)日：2016-12-21

申请号：EP14774063

申请日：2014-03-25

申请人： JFE STEEL CORP

发明人： KIMURA TATSUMI ,  UWAI KIYOSHI ,  ENDO SHIGERU ,  YAMAGUCHI MORIYASU

IPC分类号： C21D9/04 ,  C21D8/00 ,  C22C38/00 ,  C22C38/18 ,  C22C38/50

CPC分类号： C22C38/28 ,  C21D6/001 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/00 ,  C21D8/005 ,  C21D9/04 ,  C21D2211/009 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/18 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/50

摘要： A method of manufacturing a pearlitic rail according to the present invention includes: hot rolling a billet including in % by mass: 0.70% to 0.90% of C; 0.1% to 1.5% of Si; 0.01% to 1.5% of Mn; 0.001% to 0.035% of P; 0.005% to 0.030% of S; 0.1% to 2.0% of Cr, remainder of the composition consisting of Fe and inevitable impurities, so as to achieve a finishing rolling temperature of not lower than 900°C to form a rail material; and cooling the rail material in an accelerated manner at a cooling rate of 2°C /s to 30°C /s from a temperature of 770°C to 500°C, reheating the resultant or subjecting the resultant to secondary heating to a temperature within the range of 530°C to 580°C, holding the resultant at the temperature range for 20 s to 100 s, and cooling the resultant in an accelerated manner at a cooling rate of 2°C /s to 10°C /s to a temperature within the range of not higher than 450°C.