초록 ▼

An improved bleed system for a double block and bleed plug-type valve which employ a safety check valve which automatically shuts off bleed system flow upon ruptures or upon an inadvertently open manual bleed valve during normal plug valve operation. An integral component combines the safety check v

An improved bleed system for a double block and bleed plug-type valve which employ a safety check valve which automatically shuts off bleed system flow upon ruptures or upon an inadvertently open manual bleed valve during normal plug valve operation. An integral component combines the safety check valve and other bleed system components in a unitary device which is especially resistant to plumbing damage incidents.

대표청구항 ▼

[ Having thus described presently preferred embodiments of the invention, it being understood that the described embodiments are illustrative and not limiting of the scope of protection afforded hereby, what we claimed is:] [1.] A bleed system connected between the body cavity and throat cavity of a

[ Having thus described presently preferred embodiments of the invention, it being understood that the described embodiments are illustrative and not limiting of the scope of protection afforded hereby, what we claimed is:] [1.] A bleed system connected between the body cavity and throat cavity of a double block plug valve for relieving entrapped body pressure when the plug valve is closed; the bleed system comprising:a first safety check valve connected to said plug valve at said body cavity; anda second safety check valve connected to said plug valve at said throat cavity;each said safety check valve having a spring-biased ball shaped flow control device permitting bi-directional flow at rates below a selected threshold and shutting off flow in one direction at rates exceeding said threshold.