The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 2022
Filed:
Jul. 28, 2017
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Takeshi Miki, Tokyo, JP;
Yuji Arai, Tokyo, JP;
Yusuke Mihara, Tokyo, JP;
Yohsuke Uchida, Tokyo, JP;
Masahiro Yamazaki, Tokyo, JP;
Masayuki Yamamoto, Tokyo, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
A seamless steel pipe is provided that has a chemical composition which consists of, by mass %, C: 0.10 to 0.20%, Si: 0.05 to 1.0%, Mn: 0.05 to 1.2%, P≤0.025%, S≤0.005%, Cu≤0.20%, N≤0.007%, Ni: 0.20 to 0.50%, Cr: 0.30% or more and less than 0.50%, Mo: 0.30 to 0.50%, Nb: 0.01 to 0.05%, Al: 0.001 to 0.10%, B: 0.0005 to 0.0020%, Ti: 0.003 to 0.050%, V: 0.01 to 0.20%, a total of any one or more elements among Ca, Mg and REM: 0 to 0.025%, and the balance: Fe and impurities, and for which Pcm (=C+(Si/30)+(Mn/20)+(Cu/20)+(Ni/60)+(Cr/20)+(Mo/15)+(V/10)+5B)≤0.30. The steel micro-structure includes, in area %, tempered martensite ≥90%. The tensile strength is 980 MPa or more, and a Charpy impact value at −40° C. using a 2 mm V-notch test specimen is 75 J/cmor more.