Pentair / Keystone K-Lok Series 36/37

Use in pressure or vacuum, low or high pressure, bi-directional

There are many different variations available to fit your specific needs. Please Contact Us for a free quote or consultation.

Keystone Butterfly Valve K-Lok 36/37


  • K-LOK® polymer and elastomer seats provide bi-directional, drop-tight shut-off in vacuum as well as at full rated differential pressure. Its unique design does not rely on pressure to assist sealing therefore seals at high and low pressures, as well as dirty services. A variety of materials allows optimum seat life in all applications.
  • Blow-out resistant shaft is standard on all valves for increased safety.
  • Unique packing design allows for use in pressure as well as vacuum without modification or special assembly.
  • Disc taper pins are tangentially positioned half in disc and half in shaft, placing them in compression rather than shear, which eliminates potential for failure.
  • Rocker-shaped gland bridge compensates for uneven adjustment of gland nuts reducing packing leaks.
  • Integrally cast disc position stop perfectly locates the disc in seat, achieving maximum seat and seal life.
  • Extended neck allows for two inches of pipeline insulation.
  • Integrally cast mounting pad provides direct mounting of actuators eliminating the need for costly brackets and couplings.
  • Flattened body bore at shaft journal ports positions shaft bearings near disc, providing maximum shaft support resulting in reduced wear and longer life.

General applications

  • Modulating service
  • Airport refueling
  • Hydrocarbon processing
  • Chemical/petrochemical processing
  • Purified gas
  • Steam and vacuum services
  • Power and utilities
  • Refrigeration
  • HVAC
  • Alumina refining
  • Specs

    Technical data

    Size range:NPS 2 to NPS 24
    See note below for NPS 30-36
    Vacuum rating:4 x 10-5 in Hg
    Body style:Wafer, lug and double flanged
    Pressure rating:Series 36 - ASME 150
    Series 37 - ASME 300
    Temperature rating:-40°F to 1000°F
    Full compliance to API 609 standard.
    Metal seated, fire-safe and NPS 30-36 valves are available. For more information on these items see Figures 360/362 data sheet (VCTDS-00032).
    Lug and double flange bodies are full rated for bidirectional dead end service.


    Installation & Maintenance Instructions
    Series 36/37 K-Lok High Performance Butterfly Valves IOM

    Operating & Safety Instructions
    Series 36/37 K-Lok High Performance Butterfly Valves, PED O&SI

    Technical Data Sheets
    Series 36/37 K-Lok High Performance Butterfly Valves

    Technical Specification
    Series 36/37 High Performance Butterfly Valves, Seat Replacement

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