Resilient-Seated,Wafer Style,Butterfly Valve,STW Series,Lug Style,STL Series,Assured Automation

Resilient-Seated Wafer Style Butterfly Valve STW Series Resilient-Seated Lug Style Butterfly Valve STL Series

Resilient-Seated,Wafer Style,Butterfly Valve,STW Series,Lug Style,STL Series,Assured AutomationDescription:
The STW/STL is a resilient seated 125/150, ductile iron, high performance wafer style (STW) or lug style (STL) butterfly valve available with either BUNA-N or EPDM seats and a choice of disc materials (316SS, nickle plated ductile iron, or bronze). It can be equipped with a manual handle or with pneumatic or electric actuators. A full range of accessory items are available including limit switches, solenoid valves, positioners and manual override devices.

Features & Benefits

  • Economy & high performance
  • One-piece body construction and self-centering disc.
  • Seat facing acts as flange gasket.
  • 3 shaft bushings support actuation.
  • Shaft sealing against external leakage
  • Meets MSS SP-67 and API-609 specs.
  • Complete line of accessories


  • Seat - BUNA-N or EPDM
  • Disc - 316 SS - standard
    (nickel plated D.I. or bronze available)
  • Body - Epoxy Coated Ductile Iron

Available Actutors

  • Electric
  • Pneumatic (spring return)
  • Pneumatic (double acting)
  • Manual Handle Lever
  • Manual Geared Hand Wheel
  • Manual Handle with Limit Switch


  • Temperature Range:
    -4 to 194 °F (BUNA-N)
    -22 to 230 °F (EPDM)

  • Max. Pressure:
    225 PSI (2" to 12")
    160 PSI (14" to 24")

  • Pressure Testing:
    Body Hydro: 343 PSI (24 Bar)
    Seat Hydro: 243 PSI (17.6 bar)

  • Dead End Service: (Lug type only)
    Downstream Flange is recommended
    150 PSI (2" to 12")
    100 PSI (14" to 24")

End Connection

  • 2" to 12" Wafer Flange
  • 2" to 24 " Lugged Flange

Typical Applications

  • Water and waste effluent treatment plants
  • Paper, textiles and sugar industry
  • Construction industry, and drilling production
  • Heating, air conditioning, and cooling water circulation
  • Pneumatic conveyors, and vacuum applications
  • Compressed air, gas and desulphurization plants
  • Brewing, distilling, and chemical process industry
  • Transportation and dry bulk handling
    Power industry

STW (Wafer Style)
STL (Lug Style)