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:
Mar. 20, 2001
Filed:
Jan. 15, 1999
Plug and mandrel bar for seamless steel pipe rolling operation for manufacturing seamless steel pipe
Applicant:
Inventors:
Assignee:
Kawasaki Steel Corporation, Kobe, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21B 1/710 ; B21B 1/904 ;
U.S. Cl.
CPC ...
B21B 1/710 ; B21B 1/904 ;
Abstract
This invention provide a plug and a mandrel bar for use in rolling a seamless steel pipe of which life can be substantially improved more than that of the prior art under a severe condition of use always exposed to a high temperature and high load. The entire plug or the mandrel bar or at least the surface layer of the extremity end and the work section of it is made of ceramics. In addition, this invention provides a method for manufacturing a seamless steel pipe using such a plug or mandrel bar as described above.