Large bore concentric butterfly valves are selected for isolation and throttling service in water supply, water treatment, irrigation, cooling water, and municipal pipeline systems at PN6–PN16, where compact installation, low operating torque, and cost-effective large-diameter isolation are required. The concentric disc design — centered on the pipe axis with a resilient rubber seat — provides bubble-tight shut-off at low differential pressures in a compact, lightweight construction that makes butterfly valves significantly more space and cost-efficient than gate valves at large bore sizes.

Double flanged body construction is standard for large-bore butterfly valves at DN300 and above, providing structural rigidity and secure flange face integrity for pipeline bolting — preventing body distortion under pipeline loads and operating pressure that would compromise seat sealing performance in large-diameter installations. EPDM seats are standard for potable water, general water service, and cooling water applications, with NBR selected for oil-contaminated water and PTFE for chemical resistance and higher temperature service up to 180°C.

Gear operators are standard for large-bore butterfly valves where direct manual lever operation is impractical due to high operating torque at large disc diameters — with electric, pneumatic, and hydraulic actuators selected for automated remote operation, SCADA integration, and high-cycle duty in water treatment plants, pump stations, and irrigation network control systems. Design standards EN 593, API 609, and AWWA C504 govern concentric butterfly valve design, seat performance, and pressure-temperature ratings for water supply and general service applications across all bore sizes.