The Georg Fischer Type 578 Butterfly Valve features a double eccentric operating principle with an off-center disc and shaft that disengages the disc from the seal with only 3 degrees of rotation. This significantly reduces component wear and required operating torque, as the disc is not in contact with the seal during opening and closing. Compared to traditional centric (boot-style) valves, the double eccentric design requires approximately 50% less operating torque, preventing premature actuator failure and ensuring long-term reliability.

The Type 578 also incorporates a truly non-wetted shaft design. The bushing assembly has a double O-ring seal on both the disc and body sides, providing the highest level of protection and reliability. The valve is available in wafer configuration with lug option in sizes from DN40 to DN300 (1.5 to 12 inch). Body materials include PVC-U, PVC-C, PP-H, PVDF, and ABS. Seals are offered in EPDM, FPM (Viton), and NBR. The valve is certified to drinking water standards including NSF/ANSI 61, DVGW, WRAS, ACS, and KTW depending on material selection. It is suitable for water treatment, chemical processing, food and beverage, pharmaceutical, and industrial water applications. Operation can be manual (lever or gearbox), pneumatic, or electric.