The Spirax Sarco BCV30 is an electrohydraulically actuated control valve for the blowdown of steam boilers or for other high pressure drop, low flowrate applications. It is generally used with a blowdown controller as part of an automatic TDS control system.
The flowrate is adjusted by limiting the spindle stroke to regulate the number of orifices that are uncovered.
The valve, which is supplied adjusted to its low flowrate setting of 10 mm stroke, is specially designed to minimise seat erosion and ensure consistent tight shut-off.
It can be adjusted to give 15 mm stroke for medium flowrates, or to 20 mm stroke for high flowrates, by repositioning the internal cam. A valve position indicator is provided.
The valve can be opened manually by turning the actuator handwheel clockwise.
A ¼ " plug at the base of the valve may be removed to allow a sample cooler to be fitted (available from Spirax Sarco).
Operation: The valve is spring loaded to the closed position. When power is applied to the actuator the valve opens to the position set by the internal limit switch. Stroking time for the full 20 mm stroke is approximately 2 minutes to open and 8 seconds to close