Butterfly Valves

Butterfly valves are quarter-turn isolation valves that use a rotating disc to regulate or shut off flow. Because the disc sits in the center of the flow path, butterfly valves are lighter, more compact, and less expensive than gate or globe valves of the same size — which is why they dominate large-diameter water, HVAC, and process applications where a full-bore valve is not required.

G & A Valves International supplies resilient-seated, double-offset, and triple-offset butterfly valves for commercial and industrial buyers, in sizes from DN50 (2") upward — confirm the maximum stocked size with us, with larger diameters available on project order.

Product range and specifications

Resilient-seated butterfly valves (wafer, lug, flanged)

• Sizes: DN50–DN600 (2"–24")
• Pressure ratings: typical ratings PN10 / PN16 (roughly equivalent to Class 125/150) — exact ratings vary by size and model; confirm on your order.
• Body materials: ductile iron (GGG40/GGG50) bodies standard, with carbon steel and other body options available on request — confirm availability.
• Disc materials: ductile iron with nylon coating and stainless steel 304/316, with aluminum bronze discs available on request — confirm availability.
• Seat materials: EPDM (standard, −20°C to +120°C), NBR (oil service), Viton/FKM (chemical service), PTFE (corrosive service).
• Stem: stainless steel stems (grades vary by model — confirm stem material on your order).
• Connection: wafer (between flanges), lug (dead-end service), flanged (double-flanged, long pattern).
• Standards: designs based on API 609 — the primary butterfly valve design standard (Category A covers concentric soft-seated valves) — confirm design compliance on your order; face-to-face per EN 558 Series 20 (wafer) / Series 13 (flanged).
• Testing: pressure testing can be supplied to API 598 acceptance criteria — the industry standard for valve inspection and testing — on request; confirm test requirements on your quote.
• Operation: lever (DN50–DN200), gearbox handwheel (DN250+), bare stem for actuation.

Double-offset (high-performance) butterfly valves

• Sizes: confirm stocked size range on your quote.
• Pressure ratings: commonly PN16 / PN25 — confirm available ratings on your order.
• Body: cast body options commonly include carbon steel WCB and stainless steel CF8/CF8M — confirm body materials stocked.
• Seat: PTFE / RPTFE seats with stainless steel disc on selected models — confirm on your valve selection.
• Standards: Category B construction per API 609 (covers double/triple-offset, higher-pressure butterfly valves) — confirm compliance on your order.

Applications

• Water and wastewater treatment: resilient-seated valves for isolation on raw water, filtered water, and sludge lines; EPDM seats handle chlorinated water service.
• HVAC / chilled water: lug and wafer valves for isolation and balancing in commercial buildings, district cooling plants, and data centers.
• Fire protection: grooved or flanged butterfly valves for fire-main isolation — ask us about UL/FM-listed options if your specification requires listed products.
• Process and utility: general isolation on air, water, and low-pressure chemical lines in manufacturing plants.
• Oil, gas & petrochemical: double-offset (high-performance) butterfly valves for isolation on process and utility lines in refineries, terminals, and petrochemical plants — confirm suitability for your media, pressure, and temperature on your quote.
• Marine (commercial): ballast, bilge, and cooling-water service on commercial vessels — ask about type-approved models if your project requires class-society compliance.

Why buy butterfly valves from GA Valves

• Parts supply: seats, discs, stems, and operators stocked as spares — you can rebuild a valve in the field instead of replacing it.
• Assembly: valves assembled and tested before shipment; actuators mounted and calibrated on request.
• Training: hands-on valve assembly and maintenance training for your maintenance team, so replacements and rebuilds happen in-house.
• Project support: sizing assistance, material selection, and documentation packages (material test certificates and test reports available on request) for contractor submittals — confirm what documentation ships with your order.