Search This Site

(Search by Product Type i.e. Level or Brand Name i.e. Walchem)

Resilient-Seated Wafer Style Butterfly Valves

USA Toll Free: 1-800-730-0302 Tel: 416-240-1920 -

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


About Us

Metex Corporation Limited has been providing superior products and services to the process control, chemical treatment, waste water, industrial and manufacturing industries for over 25 years. It is our goal to continually provide our customers with the best possible equipment, technology, and service.


Our Products

Dataloggers, sensors, pumps, recorders, hand held instruments, flow instrumentation, level controls, valves, instrumentation, containers, tanks, transmitters, data loggers, digital indicators, mixers and agitators, pressure intrumentation, analyzers and controllers for a variety of industrial applications such as water quality, pH/ORP and more.

Website Content

Water Analyzers and Controllers, Wireless Products, Corrosion Monitoring Equipment, Cooling Tower and Boiler Controllers, a wide variety of Pumps, Valves, Dataloggers and Recorders, HVAC, Instrumentation, Skids and Systems, Containers and Tanks from world leading manufacturers are products you will find on this site.

Get in Touch