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Butterfly Valve Types and Selection Guide

7 August 2025

A butterfly valve uses a disc mounted on a shaft to control the flow path. A quarter turn moves the valve between open and closed positions. The compact construction can be useful where space and weight matter, but “butterfly valve” covers several body styles, seat arrangements and disc geometries.

The correct choice depends on the medium, pressure, temperature, required shut-off, flange arrangement, operating method and project standards. Final suitability must be confirmed against the exact manufacturer’s datasheet.

Body styles: wafer, lugged and double flanged

Wafer butterfly valves

A wafer body is installed between mating pipe flanges and is retained by the flange bolting. Check the compatible flange standard, pressure rating, gasket arrangement and installation instructions. A wafer body should not be assumed to provide end-of-line isolation.

Lugged butterfly valves

A lugged body has threaded or through-hole lugs around the body. Some product configurations are approved for specified end-of-line duties, but this capability and any reduced rating must be confirmed for the exact model and direction of pressure.

Double-flanged butterfly valves

A double-flanged body bolts directly between the adjoining pipe flanges. It may be considered where the piping layout, size or installation method calls for a flanged body. Face-to-face dimensions and flange drilling must match the system.

Concentric and offset designs

Concentric resilient-seated valves

In a concentric design, the shaft passes through the centre of the disc and the disc closes into a resilient seat or liner. The seat material is a key part of the pressure-temperature and media-compatibility assessment.

Double-offset and triple-offset valves

Offset geometry changes the way the disc and seat engage. Double-offset and triple-offset designs are available for duties that cannot be addressed by a standard concentric resilient-seated valve. The sealing system, leakage rating, operating torque and permitted pressure-temperature envelope remain product-specific.

Body style and disc geometry describe different aspects of the valve. For example, “lugged” describes the body connection arrangement; it does not by itself establish whether the valve is concentric or offset, its seat material or its service limits.

Materials and seat compatibility

Review the wetted body or liner, disc, shaft, seat and seals against the complete process conditions. A general material label is not enough. Concentration, temperature, contamination, cleaning chemicals, abrasion and cycling can change the assessment.

Elastomers and fluoropolymers have different chemical and temperature behaviour. Metallic sealing arrangements also vary. Use the compatibility and pressure-temperature information for the exact product, and obtain application confirmation where the consequences of leakage or failure are significant.

Manual and actuated operation

Lever or gearbox operation may suit manual isolation. Pneumatic and electric actuators can provide remote operation, indication or control. Actuator sizing must use the valve manufacturer’s torque data at the stated differential pressure and service conditions. Confirm operating frequency, required travel time, fail position, control signal, mounting and environment.

Butterfly valve enquiry checklist

• Medium, concentration and any solids or abrasive content.
• Normal and maximum pressure, differential pressure and temperature.
• Nominal size, pipe and flange standard, pressure class and face-to-face requirement.
• Required shut-off or control duty and permitted leakage criterion.
• Body, disc, shaft, seat or liner preferences.
• Wafer, lugged or double-flanged arrangement and any end-of-line requirement.
• Lever, gearbox or actuation requirements, including fail position and controls.
• Testing, documentation, approvals and delivery requirements.

Browse butterfly valves and request selection support

Explore the Valves4You butterfly valve range or send your application details. Valves4You Ltd can help narrow the available options once the service conditions and connection requirements are known.