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:
Jul. 17, 1984
Filed:
May. 28, 1982
Matsuo Ataka, Tokai, JP;
Itaru Aoki, Tokai, JP;
Takashi Horita, Tokai, JP;
Takehisa Nagao, Tokai, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
In a method for roll forming a flat metal strip through a roll forming machine into a round tubular product while the metal strip is being lengthwise fed therethrough, an improved method wherein regions of a specified width extending inward from the edges of said strip are imparted with substantially zero curvature. The tube forming method prevents decrease in the wall thicknesses at the edges when used in the manufacture of a thick walled electric welded pipe, and prevents the occurrence of edge buckling and springback when used in the manufacture of thick walled pipe so that in either case a proper and satisfactory butt junction for subsequent welding can be obtained.