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:
Dec. 20, 1977
Filed:
Nov. 22, 1976
Applicant:
Inventor:
Pierre H Mailliet, Howald, LU;
Assignee:
S.A. des Anciens Etablissements Paul Wurth, Luxembourg, LU;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21B / ;
U.S. Cl.
CPC ...
266273 ;
Abstract
Leakage of viscous material past an ejector piston, for example the piston of a clay gun employed in plugging blast furnace tapholes, is eliminated by a piston and ring design which exposes in excess of 50% of the leading and inner diameter surfaces of an expandable ring directly to the viscous material. Also, the leading face of the piston ring is outwardly inclined in the direction of piston travel and a complementary surface to this inclined face is provided on the piston. Expansion of the ring results from the reaction on the inclined face and inner diameter of the pressurized viscous material.