Cla-Val 50-20 - Manual

Seawater Service Pressure Relief Valve
50-20
MODEL
F
2
4
3
S C
H
REMOTE SENSING
INLET
OUTLET
DRAIN TO
ATMOSPHERE
1
Please note that if the Model 50-20 is to be used on a continuous duty
basis to maintain fire-system pressure, suitable back pressure must be
provided on the valve to prevent cavitation damage. Consult the fac-
tory for details.
• Fast Opening to Maintain Steady Line Pressure
• Accommodates Wide Range of Flow Rates
• Closes Gradually for Surge-Free Operation
• Adjustable Pressure Settings, Not Affected by
Pressure At Valve Discharge
The Cla-Val Model 50-20 Seawater Service Pressure Relief
Valve is designed specifically to automatically relieve excess
pressure in fire protection pumping systems. Pilot controlled,
it maintains constant system pressure at the pump discharge
within very close limits as demands change.
50A-20 (Angle)
Schematic Diagram
Item Description
1 100S/2100S Hytrol (Main Valve)
2 CRL Pressure Relief Control
3 X44A Strainer & Orifice Assy
4 81-01 Check Valve
Optional Features
Item Description
B CK2 (Isolation Valves)
C CV Flow Control (Closing)
F Remote Pilot Sensing
H Drain to Atmosphere
S CV Flow Control (Opening)
Specification
Sizes: Threaded Ends: 1 1/2" - 3" Materials: Main valve body & cover Adjustment 20 - 200 psi (150 class)
Globe Flanged: 2" - 36" Ductile Iron ASTM A-536* Ranges: 100 - 300 psi (300 class)
Angle Flanged: 2" - 16" Cast Steel ASTM A216-WCB*
Naval Bronze ASTM B61 *The 50G-20 (globe) and
50A-20 (angle) in cast
steel are supplied with
standard internal and
external epoxy coating
End Details: Cast Steel ANSI B16.5 Stainless Steel ASTM A743-CF-8M
Bronze ANSI B16.24 Ni. AL. Bronze ASTM B148
Stainless Steel ANSI B16.5 Super Duplex SST
Ductile Iron ANSI B16.42
Main valve trim:
Pressure 150 Class 250 psi Max. ASTM B61 Bronze Seat,
Ratings: 300 Class 400 psi Max. Monel Trim
Temperature Pilot control system:
Range: Water 180°F Max.
Cast Bronze with Monel Trim
Monel, Super Duplex Stainless Steel optional
Stainless Steel 316 Tubing & Fittings