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:
May. 09, 1989
Filed:
Jan. 29, 1987
Applicant:
Inventors:
Assignee:
Showa Aluminum Corporation, Osaka, JP;
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; F16L / ;
U.S. Cl.
CPC ...
428654 ; 138143 ;
Abstract
A hollow extrudate for use in a vacuum is produced by a process comprising the steps of hermetically closing the forward open end of a hollow shaped material immediately after extrusion from a billet, cutting the shaped material after a predetermined length thereof has been subsequently extruded and hermetically closing the cut end at the same time, and cutting off the closed ends. The billet is a composite material composed of a core of aluminum having a high purity of at least 99.9% and an aluminum alloy cladding. The extrudate obtained has an inner layer and an outer layer corresponding to the core and the cladding, respectively.