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:
Jul. 26, 1994
Filed:
Apr. 28, 1993
Applicant:
Inventor:
David Mills, Bristol, GB;
Assignee:
Rolls-Royce plc, London, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B22D / ;
U.S. Cl.
CPC ...
164132 ; 134-2 ; 134-3 ; 134 21 ; 134 221 ; 134 2217 ;
Abstract
The article together with the alumina core in situ is placed in a sealable vessel containing a concentrated aqueous potassium hydroxide leaching liquor at a temperature immediately below its normal atmospheric boiling point. The vessel is sealed and the pressure within the vessel is reduced to less than atmospheric pressure so as to induce boiling and agitation of the leaching liquor within the passage in the article. The pressure in the vessel is raised to atmospheric pressure and finally spent leaching liquor together with leached alumina core is removed from within the article.