- 专利标题： High-strength seamless steel pipe for oil country tubular goods, and method for producing the same
-
申请号： US16333029申请日： 2017-09-13
-
公开(公告)号： US11313007B2公开(公告)日： 2022-04-26
- 发明人: Masao Yuga , Mitsuhiro Okatsu
- 申请人： JFE Steel Corporation
- 申请人地址： JP Tokyo
- 专利权人： JFE Steel Corporation
- 当前专利权人： JFE Steel Corporation
- 当前专利权人地址： JP Tokyo
- 代理机构： RatnerPrestia
- 优先权： JPJP2016-203347 20161017
- 国际申请： PCT/JP2017/033007 WO 20170913
- 国际公布： WO2018/074109 WO 20180426
- 主分类号： C21D6/02
- IPC分类号： C21D6/02 ; C21D8/10 ; C21D9/08 ; C22C38/00 ; C22C38/02 ; C22C38/04 ; C22C38/06 ; C22C38/22 ; C22C38/24 ; C22C38/26 ; C22C38/32 ; C22C38/44 ; C22C38/46 ; C22C38/48 ; C22C38/54 ; C22C38/20 ; C22C38/28 ; C22C38/42 ; C22C38/50
摘要：
Provided herein is a high-strength seamless steel pipe containing a particular chemical composition. The volume fraction of tempered martensite is 90% or more in terms of a volume fraction. The number of nitride inclusions with a particle diameter of 4 μm or more is 50 or less per 100 mm2, the number of nitride inclusions with a particle diameter of less than 4 μm is 500 or less per 100 mm2, the number of oxide inclusions with a particle diameter of 4 μm or more is 40 or less per 100 mm2, and the number of oxide inclusions with a particle diameter of less than 4 μm is 400 or less per 100 mm2 in a cross section perpendicular to a rolling direction.