The ProSeal range of Butterfly valves is available in a wide range of sizes and materials and provides a cost-effective solution where valves are required for utility type applications. The valve has an easily replaceable cartridge type liner comprising a rubber seat with a phenolic backing. The cartridge is pressed into the body, secured by means of the shaft and is therefore blow out proof and particularly suited for use on vacuum applications. The thickness of the rubber seat is optimised, therefore reducing possible swelling, and the hard-phenolic backing minimises distortion of the rubber when tightening the valve between flanges. These design features ensure that the valves operate with the minimum torque requirement, and mean that, unlike those with loose liners they can be installed with the blade in the closed position, thus eliminating any possibility of damage to the blade during installation. The two-piece pinless shaft enhances the CV of the valve and the square drive between the disc and the shaft is free from media ingress and possible corrosion therefore allowing easy removal for service irrespective of time in service.
Shaft ends available in ISO square allowing direct mounting