Invention Grant
US08210019B2 Method for producing pearlitic rail excellent in wear resistance and ductility
有权
生产珠光体钢轨的优良耐磨性和延展性的方法
- Patent Title: Method for producing pearlitic rail excellent in wear resistance and ductility
- Patent Title (中): 生产珠光体钢轨的优良耐磨性和延展性的方法
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Application No.: US12309439Application Date: 2007-07-24
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Publication No.: US08210019B2Publication Date: 2012-07-03
- Inventor: Masaharu Ueda , Kazunori Seki , Takuya Sato , Takeshi Yamamoto
- Applicant: Masaharu Ueda , Kazunori Seki , Takuya Sato , Takeshi Yamamoto
- Applicant Address: JP Tokyo
- Assignee: Nippon Steel Corporation
- Current Assignee: Nippon Steel Corporation
- Current Assignee Address: JP Tokyo
- Agency: Kenyon & Kenyon LLP
- Priority: JP2006-200860 20060724; JP2007-174800 20070703
- International Application: PCT/JP2007/064839 WO 20070724
- International Announcement: WO2008/013300 WO 20080131
- Main IPC: B21B23/00
- IPC: B21B23/00 ; B21D37/16

Abstract:
The invention provides a method for producing a pearlitic rail by rough hot rolling and finish hot rolling a billet. In the finish hot rolling, the billet is rolled at a rail head surface temperature in a range of not higher than 900° C. to not lower than the Ar3 transformation point or Arcm transformation point to produce a head cumulative reduction of area of not less than 20%, where the reaction force ratio of the finish rolling is not less than 1.25. The finish hot rolled rail head surface is subjected to accelerated cooling or spontaneous cooling to a temperature of 550° C. or less at a cooling rate of 2 to 30° C./seconds, thereby refining the rail head structure to attain a hardness within a predetermined range, and improving rail wear resistance and ductility.
Public/Granted literature
- US20090314049A1 METHOD FOR PRODUCING PEARLITIC RAIL EXCELLENT IN WEAR RESISTANCE AND DUCTILITY Public/Granted day:2009-12-24
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