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:
Feb. 23, 1988
Filed:
May. 01, 1986
Yutaka Sunaga, Kawasaki, JP;
Toshio Sakurai, Yokohama, JP;
Sanwa Kokan Kabushiki Kaishas, Yokohoma, JP;
Abstract
A method of cold drawing seamless metal tubes each having an upset portion on each end. A draw bench used for carrying out the method of this invention comprises a die control device, a plug control device including a plug having large and small diameter bearing portions and a draw unit. The die control device and the plug control device are movable with each other for changing a cross sectional reducing area between the reducing die and the plug. The method is characterized in that the cross sectional reducing area between the reducing die and the plug is preferably changed in accordance with the desired forms of a mother tube to be drawn by longitudinally transferring the reducing die and the plug and fixing them at the selected positions.