Valveco Wafer Butterfly Valves from HMA Flow & Industrial feature an ISO square drive for sizes 50 mm to 300 mm, and a positive keyed drive for sizes 350 mm and above. Four self-lubricating bronze bushes provide maximum stem support, with minimum friction. Potential stem seizure is eliminated. Pressure surge seals (O rings) are moulded inside the seat stem hole area to provide failsafe sealing around the stem, eliminating possible leakage.

A phenolic resin backed seat provides support for the seat, which is non-collapsible, stretch-resistant, blowout-proof, and suitable for vacuum. A precision profile disc provides bubble-tight shutoff with minimal disc/seat interference, assuring minimum torque and longer seat life. Universal flange adaptability allows any for wafer style in the size range. It suits ANSI 125, DN16, and AS 2129 Table D and E. An actuator mounting flange conforms to ISO 5211, and accommodates all types of operators, lever, gear, electric, hydraulic, and pneumatic.

An O ring weather seal prevents ingress of moisture and external material into the stem area. A one-piece thru-stem design ensures dependability and positive disc control. An internal square drive and precision taper pins ensure positive, vibration-proof, stem-to-disc connection. The polished disc flats mate with the seat flats to give a highly-efficient seal that prevents leakage into the stem area. A supported stem seal protects against distortion, a common cause of stem leakage. Valveco Wafer Butterfly Valves from HMA Flow & Industrial are fusion-bonded epoxy-coated.