Pressure Relief Valve

Pressure Relief Valve

  • FM Approved Logo Mid Grey 300.jpg
  • UL Logo Mid Grey.jpg
Size range 50mm to 300mm
Body Pattern Globe, Angle
Working pressure 150 to 250 (300 to 400psi) max
Maximum Working temperature Up to 85°C (185°F)
Inlet connection Flanged
Outlet connection Flanged
Material Ductile Iron - ASTM A536
Finish Red Epoxy Coated
Approvals FM Approved, UL Listed

The Cla-Val Model 50B-4KG1 (Globe) / 2050B-4KG1 (Angle) 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.

Advantages include:
  • U.L. Listed / U.L.C. Listed/FM Approved
  • 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
How it works:
At pump start, Cla-Val Relief Valve modulates to relieve excess pump capacity, maintaining positive system pressure at the pump discharge.
 
When fire demand slows or ceases, Cla-Val Model  50B-4KG1 opens, diverting entire pump output to discharge, allowing fire pump to be stopped without causing surging in the lines.

Valve Capacity Table

Valve Size mm 50 65 80 100 150 200 250 300
NFPA 20 Maximum
Recommended LPM
(litres per Min)
787 1136 1893 3785 9464 18927 41640 60567

 

Dimensions

Value Size (mm) 50 65 80 100 150 200 250 300
Threaded Ends  238 279 318 - - - - -
A 150 Flanged 238 279 305 381 508 645 756 864
300 Flanged 254 295 337 397 533 670 790 902
300 x 150 - - 327 389 522 657 773 883
B 84 102 116 146 200 254 330 356
C 305 311 318 330 363 414 457 522
D 38 43 65 81 109 135 235 273
Threaded Ends 121 140 159 - - - - -
E 150 Flanged 121 140 152 191 254 324 378 432
300 Flanged 127 149 162 200 267 337 395 451
Threaded Ends 83 102 114 - - - - -
E 150 Flanged 83 102 102 127 152 203 219 349
300 Flanged 89 109 111 135 165 216 236 368
G & H 152 170 197 200 216 248 337 362