Hydraulic Pressure Control Valves - 50-01 & 650-01 Pressure Relief & Sustaining Valve | Cla-Val | Philippopoulos s.a.
Hydraulic Pressure Control Valves - 50-01 & 650-01 Pressure Relief & Sustaining Valve | Cla-Val | Philippopoulos s.a.

Hydraulic Pressure Control Valves - 50-01 & 650-01 Pressure Relief & Sustaining Valve | Cla-Val

Cla-Val 50-01 / 650-01

Hydraulically operated, pilot-controlled modulating pressure relief and sustaining valve. Maintains a preset upstream pressure and opens progressively when inlet pressure exceeds the set point. Used as a pressure relief, pressure sustaining, back pressure, or unloading valve in bypass lines.

Operation

Line pressure is sensed by the pilot circuit. When upstream pressure rises above the set point, the main valve opens proportionally to relieve excess flow. The valve closes in a controlled manner when pressure drops below the set point. No external power supply is required for standard operation.

Typical Applications

  • Pump bypass in water distribution networks
  • Pipeline overpressure protection
  • Maintaining minimum suction or discharge pressure
  • Back pressure control in industrial water systems
  • Unloading function in pump stations

Variants

  • 50-01: Full port design for maximum flow capacity.
  • 650-01: Reduced port for improved control stability at lower flow rates.

Selection Criteria

Sizing is based on required relief flow, set point, available backpressure, allowable flow velocity, and cavitation risk. For high differential pressure (ΔP), consider anti-cavitation trim or staged relief configurations. Valve selection should account for media compatibility with body, trim, and elastomer materials.

FAQ

Is this a safety valve?
No. This is a pressure control valve and does not replace a certified safety relief valve per pressure vessel codes.

Is electrical power required?
No. Standard operation is fully hydraulic.

Suitable media?
Water and compatible liquids with valve body, trim, and elastomer materials.

Standard (Options)
  • ANSI
Connection (Options)
  • Flanged
Material (Options)
  • Bronze
  • ASTM A216 WCB
  • Ductile Iron
Pressure Rating (Options)
  • 150 lbs
  • 300 lbs

Datasheet and documents

Description

Cla-Val Models 50-01 and 650-01 Pressure Relief Valves are hydraulically operated, pilot-controlled, modulating valves designed to maintain constant upstream pressure within close limits. Model 50-01 is the full port version of the valve. Model 650-01 is the reduced port version of the valve. Both are ideal for pressure relief, pressure sustaining, back pressure, or unloading functions in a by-pass system.

Pressure Sustaining Service: When installed in a line between an upper zone and a lower area of heavy demand, the valve acts to maintain desired upstream pressure to prevent “robbing” of the upper zone. Water in excess of pressure setting is allowed to flow to an area of heavy demand, control is smooth, and pressure regulation is positive.

Pressure Relief Service: This fast opening, slow-closing relief valve provides system protection against high-pressure surges on pump start-up and pump shut down by dissipating the excess pressure to a safe location.