Ames Fire & Waterworks 951GS Stainless Steel Rate-of-Flow Control Valve with Pressure Reducing Feature - Manual

01/06
950 Series Model
8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.amesfirewater.com
RATE-OF-FLOW VALVE with
PRESSURE REDUCING FEATURE
951
651
Operation
The AMES Model 951 / 651 Rate of Flow Control Valve with Pressure Reducing Feature is designed to
automatically limit flow rate to a constant, adjustable, maximum, and reduce a fluctuating higher upstream
pressure to a constant lower downstream pressure. In most applications, the Pressure Reducing function
will be secondary to the primary Flow Control Function.
The flow control action of the valve is controlled by a normally open, differential control pilot designed to: 1)
Open (allowing fluid out of the main valve cover chamber) when the differential pressure across the orifice
plate is below it’s adjustable set point, and, 2) Close (allowing fluid to fill the main valve cover chamber) when
the differential pressure across the orifice plate is above it’s adjustable set point. A decrease in differential
pressure causes the valve to modulate towards an open position, increasing flow rate. An increase in
differential pressure causes the valve to modulate towards a closed position, decreasing flow rate.
The pressure reducing action of the valve is controlled by a normally open, pressure reducing pilot designed
to: 1) Open (allowing fluid out of the main valve cover chamber) when downstream pressure is below the
adjustable setpoint, and 2) Close (allowing fluid to fill the main valve cover chamber) when downstream
pressure is above the adjustable setpoint. A decrease in downstream pressure causes the valve to modulate
toward an open position, raising downstream pressure. An increase in downstream pressure causes the
valve to modulate toward a closed position, lowering downstream pressure.
The Orifice Plate Assembly should be installed three to five pipe diameters downstream of the Model
951 / 651, and field connected with 3/8” minimum copper tubing in accordance with factory piping
schematic. Please specify desired flow rate prior to ordering.