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:
Nov. 30, 1993
Filed:
Dec. 29, 1992
Applicant:
Inventors:
Assignee:
Usui Kokusai Sangyo Kabushiki Kaisha, Shizuoka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21C / ;
U.S. Cl.
CPC ...
228127 ; 228131 ; 138143 ; 138145 ; 427239 ;
Abstract
A small thick-walled composite metal fuel injection tubing for a diesel engine, for example, is manufactured from an outer carbon steel pipe, and an inner stainless steel pipe press-fitted in the large diameter carbon steel pipe by drawing. The press-fitted mating surfaces of the inner and outer pipes are metallurgically and integrally bonded together by heat-treating. As a result, at least an inside wall surface of the inner stainless steel pipe has a diffused layer of at least one kind of metal, or an alloy of two or more kinds ,of metals in combination, selected from the group consisting of Ni, Cr, Mo, Co, Al and Cu.