DOUBLE-SEATED SHUTOFF VALVE

摘要

A new valve device adapted specifically for use with hot erosive flow streams is provided. This valve device has an inner plug head, which modulates and throttles the amount of flow passing through the valve when the valve is open. The inner plug head is shaped so that as the valve plug approaches the closed position, the inner plug head blocks most of the flow path, reducing the flow to a small amount. The valve of this invention has an outer plug head the contacts the valve's outer ceramic seat as the valve reaches the closed position. Contact between the outer ceramic seat and the outer ceramic plug entirely shuts off flow through the valve.