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. 05, 2016
Filed:
Apr. 05, 2013
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Osamu Miyahara, Tokyo, JP;
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
Abstract
In performing cold rolling on a seamless pipe as a mother pipe, it is possible to inhibit the generation of metal chips from the end portions of the mother pipe, and to prevent the formation of indentations therein that may be caused by the metal chips to thereby provide good surface appearance. This is made possible by using a mother pipe () having end portions at the cold rolling starting side and finishing side that have been R-chamfered, at each outer edge and at each inner edge, such that (T−T)/2≦R≦T/2 is satisfied, where R is a radius (mm) of the R-chamfer on the outer edges and the inner edges of the end portions, Tis a wall thickness of the mother pipe, and Tis a wall thickness of the pipe after cold rolling.