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. 07, 1976
Filed:
Feb. 03, 1975
Applicant:
Inventors:
Hisashi Gondo, Kisarazu, JA;
Masatoki Nakayama, Kisarazu, JA;
Hajime Nakasugi, Kisarazu, JA;
Masanobu Yamaguchi, Kimitsu, JA;
Assignee:
Nippon Steel Corporation, Tokyo, JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D / ; C21D / ;
U.S. Cl.
CPC ...
148 / ; 148 124 ; 148150 ; 148153 ;
Abstract
A method for producing a large diameter steel pipe having excellent shape, toughness and tensile strength by subjecting the pipe to descaling and to heat treatment which involves heating the steel pipe locally successively from one end to the other end of the steel pipe in the axial direction and forcedly cooling the pipe, and then expanding the steel pipe after the heat treatment.