The valve utilises elastomer seats and seals and their surge to popularity can be attributed to these adavantages. In somes cases, they may be used for non-critical throttling applications. They are lighter in weight than conventional valves. The position of the lever indicates whether they are wide open, partially open or fully closed.

Butterfly valves are compact and space-saving and easily installed in new piping or as replacements in existing piping. They are easily adapted to lever, manual, gear, electric or pneumatic operation.

They are widely used in mechanical services as isolation valves on chilled and condenser water; the valves are designed so that lagging does not interfere with the valve operator.

The wafer type valve is designed for quick installation between flanges. No gaskets are required because of the moulded resilient liner which is keyed into the recesses in both faces of the body ends.

Typical butterfly valves in the John Valves range are our figure numbers IBFW, and 900 Series, and more details may be found in our Online Valve Catalogue.