|Operation||Nominal Ambient Temperature||Valve Parts in Contact with Fluids|
|ASCO's patented adjustable flow control design has greater flow capacity than most conventional constructions where a separate adjustment speed control and ball check for free flow are utilized.
A spring loaded disc allows free flow in one direction and an adjustable or controlled flow in the opposite direction. Flow adjustment is performed by a tapered brass stem that controls the flow through the cross hole in the disc.
|Valves may be mounted in any position.
The adjustable knob contains a unique locking device that consists of a plastic metering knob and thumb latch pawl. The valve bonnet is scribed with graduations to serve as a position indicator for the stem
|When the pawl is in the up position, it creates a friction lock on the knurled bonnet and the knob cannot rotate. When the pawl is at 90° to the knob, the knob is free to rotate.||125°F Maximum.||Body and Stem -- Brass
Seals -- Buna "N" Disc -- Acetal Spring -- 302 s.s. Retainer -- 17-7PH s.s.
|Catalog Number||Pipe Size (ins.)||Orifice Size (ins.)||CV Flow Factor ¹||Operating
|Meter||Free||Air-Inert Gas, Water and Light Oil|
|NOTE: 1 -- Refer to Chart A for Cv vs. Metering Stem Turns.|
for ASCO Flow Control Valves
Metering Stem Turns
|Example I: A ½" N.P.T. flow control valve is required to pass 3 GPM of water at a p of 16 psi. Determine the position of the metering stem.
From the graph for the ½" N.P.T. flow control valve with a Cv of .75 the stem should be positioned three turns out from fully closed.
Example II: To determine the flow using the same data of 16 psi, and METERED Cv fo .75, the solution will be:
GPM = Cv = .75 = 3
Example III: The flow through this valve in the FREE FLOW position is: GPM = Cv* = 2.6 = 10.4
*Cv is obtained from the free flow data table.
P1 -- Inlet Pressure (PSIA)
P2 -- Outlet Pressue (PSIA)
p -- Pressure Drop (P1 - P2) psi
G -- Specific Gravit of Gas @ 14.7 PSIA and 60°F
T -- Absolute Temperature of Flowing Medium (°F + 460)
|GPM = Cv||SCFH =||Cv 960|