Keystone Butterfly Valve ready for delivery
The Figure 990 butterfly valve has a split, wafertype body, features a one piece disc stem and field replaceable seat. The range of available materials makes these valves suitable for a wide variety of applications.
- Factory testing of every valve at full rating ensures 100% bubble-tight shut-off.
- Standardized actuator flange for easy operator interchangeability and mount direct to Keystone Range of actuators.
- One-piece wafer-thin disc-stem provides high strength and absolutely positive disc control and gives the very minimum obstruction to flow. Its crevice free surface makes it ideal for hygienic duty.
- Primary seal formed by the seat/shaft/hub contact exceeds the pressure rating of the valve. Body is totally isolated from the flowing medium.
- Secondary shaft seal is suitable for pressure and vacuum is self adjusting.
- Patented dove-tail seat requires no bonding. Makes seat replacement simple and fast. Extra heavy edge section resists tearing.
- Hub seal is provided by preloaded contact between flatted seat surface and rounded polished disc-hub area for positive sealing at all disc positions.
- Molded-in O-ring provides positive flange sealing and eliminates the need for gaskets.
- Heavy duty top bushing absorbs side thrust loads. Self-adjusting sealing for both directions is also suitable for vacuum.