Pilot Operated Pressure Reducing Valve


PREDU® P, our pilot operated pressure reducing valve with precise control – even with high and widely varying flow rates and inlet pressures.

The PREDU® P is a self-acting pilot operated pressure reducing valve for use on steam and air, that will accurately control downstream pressure (P2), regardless of the upstream pressure (P1), or demand from the system. A pilot valve senses the downstream pressure (P2) which in turn controls the main valve. The result is a very narrow proportional band which together with the low hysteresis enables very precises and stable pressure control.

Your Advantages

  • Accurate pressure control, even at high and variable flow rates
  • PFAS free design
  • Even easier to service due to hardened reversing plug (plug sealing surfaces on both sides)
  • Robust and resistant piston design
  • Easier maintenance because of removable piston guide
  • Cost-saving due to internal pressure sensing. External pressure sensing lines are available but not necessary.

Product Features PREDU® P

Technical Data

StandardsDIN EN; ANSI
Nominal pressuresPN 16; PN 25; PN 40 (DIN EN)
Class 150; Class 300 (ANSI)
Nominal diametersDN 15 – 50  (DIN EN)
1/2" – 2" NPT and G (ANSI)
Temperature range0 °C – +220 °C
Upstream pressure range2 barg – 16 barg
Body materials1.0619; 1.4408 (DIN EN)
Sealing types PFAS free sealing
Plug typesReversible plug (ground on both sides)
Connection typesFlanges; screwed connection
Body types Straight through body
ActuatorsPilot operated

Areas of Use

Markets (excerpt)
  • Industry
  • HVAC
  • Shipbuilding
  • Oil & Gas
  • Chemicals
  • Pharmaceuticals & Biotechnology
  • Food & Beverages
  • Energy
Applications (excerpt)
  • Pressure reduction with variable pre-pressures and mass flows while maintaining constant control quality
  • Autoclaves for sensitive products
  • Heating jackets in the chemical industry
  • Heat exchangers with a low temperature tolerance specification
  • Uniform tank heating
  • Sterilisation with steam
  • Systems for precise pressure control (e.g. calender roll presses)
Flow Media
  • Steam
  • Air

Pressure reducing station with pilot operated pressure reducing valve PREDU® P



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