Cla-Val Flow Control/Rate of Flow Control Valves prevent excessive flow by limiting flow to a preselected maximum rate, regardless of changing line pressure. The pilot control responds to the differential pressure produced across an orifice plate installed downstream of the valve. Accurate control is achieved as very small changes in the controlling differential pressure produce immediate corrective action of the main valve.

Cla-Val Flow Control Valves are available in various configurations including the ubiquitous Model 40-01 Rate of Flow Control Valve, Model 43-01 Combination Rate of Flow Controller and Shut-Off Valve, and Model 49-01 Combination Rate of Flow and Pressure Reducing Valve.

A typical application for this type of automatic control valve is as a pressure type filter effluent control valve where a constant flow rate is maintained despite variation in head loss through the filter, or anywhere a constant rate of flow is desired.