Keystone Figure 129/139 Butterfly Valves

  • Keystone Figure 129/139 heavy duty resilient seated butterfly valves feature a steel reinforced cartridge design seat.
  • These valves are available in both wafer and lugged body style, and in a variety of materials including heavy duty bronze making the valve ideal for marine and offshore platform applications where salt water corrosion is a challenge.
  • Replaceable, metal-reinforced seat, completely encapsulated by rubber, isolates the stem and body from the media and eliminates seat distortion due to high vacuum or turbulence.
  • Primary stem seal, formed by preloaded contact of disc hub with flatted seat surfaces, completely isolates stem and body from the line media.
  • Secondary stem seal, formed by an engineered interference fit of the stem through the seat, provides additional sealing integrity.
  • Rounded, polished disc edge provides full 360 degree concentric seating, minimum flow restriction, lower seating and unseating torques and maximum seat life.
  • Superior, one-piece thru-shaft design provides high-strength and positive disc control. Shaft ends are standardized for operator interchangeability.
  • Self-locking disc screws allow quick and easy disassembly and provide a positive connection.
  • Self-adjusting, bi-directional stem seal is suitable for full industrial vacuum and pressure, preventing external contamination of the stem area.
  • Heavy-duty, corrosion-resistant top bushing absorbs actuator side thrust loads.
  • Each valve is factory tested to 110 percent of specified pressure rating assures drop-tight shut-off.
  • Cast-in top plate is an integral part of the body and is standardized to allow direct mounting of all Keystone actuators.