VALVE SHAFT APPARATUS FOR USE WITH ROTARY VALVES

摘要

A valve shaft apparatus with a rotary valve includes a shaft having a first portion in an opening of a valve body and a second portion in a cavity of a closure member. A first seal is coupled to the first portion to prevent fluid leakage into the opening of the valve body, where the first seal defines a first leakage detection area. A second seal is coupled to the second portion to prevent fluid leakage into the cavity, the second seal is to define a second leakage detection area. A passageway in the shaft is fluidly coupled to the first and second leakage detection areas to provide an indication of fluid leakage past the first seal in the opening or to detect fluid leakage past the second seal in the cavity. The passageway is in fluid communication with a shaft outlet formed in an end of the shaft.