Available in 1” to 6” (25mm – 152mm) OD sizes.


Product Wetted: ASTM 316L (UNS-S31603); (DIN-1.4404)

Non-Product: ASTM 304 (UNS-S30400); (DIN-1.4301)

Seat Material:

  • Metal
  • Tri-Ring


  • FKM (Standard)

  • EPDM (Option)

Finish: < 32Ra (<0.8 µm) Other finishes available upon request


Models & Functions 

W68 Series- Throttling

W88 Series- Aseptic Stem Flush Throttling

W682 or W88- Divert Throttling 

W685 or W885- Non-Slamming Divert Throttling 


Positioner Configurations

Pneumatic Moore positioners use 3-15 psi  pneumatic control signal and air supply to drive seat plug into a certain position

Burkert Electropneuamitc positioners use a 4-20 mA electronic feedback signal between the valve stem sensor and a solenoid in the control top which adds or vents air into the actuator to move the plug seat up or down depending on the desired position.