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. 18, 1983
Filed:
Jul. 09, 1981
Applicant:
Inventor:
Tateo Yamada, Amagasaki, JP;
Assignee:
Sumitomo Kinzoku Kogyo Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21B / ;
U.S. Cl.
CPC ...
72 68 ; 72 97 ; 72368 ;
Abstract
The present invention relates to manufacturing process of seamless metal tubes by elongating mill such as Mannesmann mandrel mill. Shells are subjected to rolling operation with main object of wall thickness equalization by means of a rotary mill having 3 rolls without any internal tools such as mandrel bar or plug. This process improves wall eccentricity and enables to decrease the number of billets as materials for tube making.