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:
Jan. 17, 1978
Filed:
Sep. 13, 1976
Bertram L Morrison, Houston, TX (US);
ACF Industries, Incorporated, New York, NY (US);
Abstract
A pair of seat ring members are loosely mounted in annular recesses around the longitudinal bore in a gate valve body at the intersection of the bore and the valve chamber on opposite sides of the gate member. Each of the seat ring members has a rear face comprised of a pair of stepped portions connected by an outwardly facing annular surface portion. Each seat ring has a groove at the juncture of the outer stepped surface portion and the outwardly facing annular surface. A seal ring chamber is formed between the recess annular wall, the stepped outer surface portion, the outwardly facing annular surface and the groove. A resilient O-ring is positioned in the seal ring chamber. The O-ring has a sufficient cross section to seal between the recessed end wall and the outwardly facing annular surface when initially positioned in the seal ring chamber upon assembly of the valve. When an unbalanced pressure condition is present across the downstream O-ring then that O-ring is displaced radially inward and partially enclosed in the groove in order to prevent excessive compression thereof, while at the same time the upstream O-ring maintains a seal between the upstream recess end wall and the upstream outwardly facing annular surface.