Cla-Val 90-72/690-72 - Manual

CLA-VAL 90-72/690-72
Pressure Reducing Valve
Pressure Reducing Valve with
Low Flow By-Pass
Typical Applications
This valve has the flexibility to be installed in a distribution
system where the demand varies over a wide range. This fre-
quently occurs in industrial, residential, educational, high-rise
buildings and other applications. Another important feature of
the valve is its space efficient configuration, allowing easy
installation and maintenance.
Schematic Diagram
Item Description
1 Hytrol (Main Valve)
2 X47A Ejector
3 CRD Pressure Reducing Control
4 990 Pressure Reducing Valve
5 CK2 (Isolation Valve)
Optional Features
Item Description
A X46A Flow Clean Strainer
B CK2 (Isolation Valve)
C CV Flow Control (Closing)*
D Check Valves with Isolation Valve
M
X144 e-FlowMeter
P X141 Pressure Gauge
S CV Speed Control (Opening)*
V X101 Valve Position Indicator
Y X43 "Y" Strainer
* The optional closing speed control on this valve should
always be open at least three (3) turns off its seat.
• Modulating Control
• Maintains Constant Outlet Pressure Over a
Wide Range of Flows
• Durable Construction
• Convenient and Space Saving
The Cla-Val Model 90-72/690-72 Pressure Reducing Valve with
Low Flow By-Pass automatically reduces a higher inlet pressure
to a steady lower downstream pressure, regardless of changing
flow rate. The low flow by-pass capability is achieved by using
the Cla-Val Model 990 Direct Acting Pressure Reducing Valve as
an integral part of the main valve. By doing this, space is saved
and installation and maintenance become much easier.
The pressure reducing valve is hydraulically operated and
controlled by a Cla-Val CRD pilot control, which senses pressure
at the main valve outlet. An increase in outlet pressure forces the
CRD pilot control to close and a decrease in outlet pressure
opens the control. This causes the main valve cover pressure to
vary, modulating the main valve, thereby, maintaining constant
outlet pressure.
The Model 990 low flow pressure reducing by-pass is set to a
higher pressure than the CRD pilot control. The 990 responds to
pressure changes at the main valve outlet. When the CRD
closes, the Model 990 remains open, allowing low flow to
by-pass the main valve. The 990 closes when the flow
decreases and the downstream pressure reaches its set-point.
The Cla-Val Model 90-72/690-72 is not a substitute for a low flow
bypass valve in all cases. This valve is commonly used in
building where 1-15 gpm low flows are common in off peak
usage.The bypass on this valve is limited to the body tapping
size on the main valve.
90-72
MODEL
(Full Internal Port)
690-72
(Reduced Internal Port)