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:
Oct. 02, 2012
Filed:
Aug. 07, 2009
Akihito Yamane, Kyoto, JP;
Akihito Yamane, Kyoto, JP;
Sumitomo Metal Industries, Ltd., Osaka, JP;
Abstract
A pipe in which polygonization is substantially eliminated is manufactured by a reducer with a grooved roll with a groove having a groove bottom zone including the center of the groove in the roll axial direction and flange zones adjoining both sides of the groove bottom zone. The groove surface has a friction distribution in the roll axial direction such that the frictional force with respect to a material being rolled in the groove bottom zone is larger than the frictional force with respect to a material being rolled in the flange zones. This friction distribution can be achieved by working the groove surface so that the surface roughness of the groove bottom zone becomes greater than the surface roughness of the flange zones or by applying a lubricity modifier which differs with respect to amount and/or type between the groove bottom zone and the flange zones.