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:
Jan. 29, 2019
Filed:
Mar. 07, 2016
Applicant:
Jfe Steel Corporation, Tokyo, JP;
Inventors:
Hisakazu Tajika, Tokyo, JP;
Satoshi Igi, Tokyo, JP;
Assignee:
JFE Steel Corporation, , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16L 9/00 (2006.01); B21C 37/16 (2006.01); B21C 37/30 (2006.01); B21C 37/08 (2006.01); F16L 9/02 (2006.01); B23K 101/06 (2006.01); B23K 31/02 (2006.01);
U.S. Cl.
CPC ...
B21C 37/16 (2013.01); B21C 37/0803 (2013.01); B21C 37/30 (2013.01); F16L 9/006 (2013.01); F16L 9/02 (2013.01); B23K 31/027 (2013.01); B23K 2101/06 (2018.08);
Abstract
In a steel pipe having a waveform shape formed on an outer diameter thereof by a pipe expansion process, a value a/w is 0.038% or less, where a and w denote an amplitude and a wavelength of the waveform shape, respectively. A method of manufacturing a steel pipe having a waveform shape formed on an outer diameter thereof by a pipe expansion process includes a step of forming the waveform shape such that a value a/w is 0.038% or less, where a and w denote an amplitude and a wavelength of the waveform shape, respectively.