| General-purpose water and HVAC valves | Concentric, resilient-seated wafer, lug, or flanged butterfly valves | Often DN50–DN1200; commonly PN10 or PN16, with Class 150 options | Ductile iron or cast iron body; EPDM or NBR seat; ductile iron or stainless-steel disc options | Water distribution, building services, cooling-water systems, and low-pressure process lines | EN 593; API 609; ISO 5752; applicable GB/T product requirements |
| Industrial process and higher-performance valves | Double-eccentric (high-performance) butterfly valves, commonly wafer, lug, or flanged | Often DN50–DN2000; pressure classes vary, with PN10–PN25 and Class 150–300 options common in product ranges | Carbon-steel or stainless-steel body; stainless-steel disc; PTFE, reinforced PTFE, or elastomer seats | General process service, utilities, pulp and paper, and selected chemical applications | API 609; EN 593; ASME B16.34 where specified; pressure and temperature limits for the selected seat |
| High-temperature or tight-shutoff service | Triple-offset, metal-seated butterfly valves | Available in a wide range of sizes; product offerings may extend from DN50 to large-bore sizes, with pressure classes selected by design | Carbon steel, stainless steel, or alloy steel; metal-to-metal sealing surfaces, sometimes with hard-facing | Steam, hot oil, gas, power generation, and other services requiring metal seating | API 609; ASME B16.34 where applicable; relevant fire-safe or emissions requirements when specified |
| Large-diameter waterworks valves | Large-bore resilient-seated or double-eccentric butterfly valves, often flanged | Commonly supplied from several hundred millimetres to multiple metres in diameter; pressure is often in the low-to-medium range and must be confirmed per design | Ductile iron or fabricated steel body; elastomer seat; coated internal and external surfaces may be offered | Water treatment plants, pumping stations, reservoirs, and municipal transmission pipelines | AWWA C504 for applicable waterworks designs; EN 593; ISO 5752; project-specific coating requirements |
| Corrosion-resistant and lined valves | Resilient-seated or lined butterfly valves with protected wetted surfaces | Often offered in small- to medium-bore sizes, commonly up to around DN600; allowable pressure depends on lining, temperature, and construction | PTFE or other specified lining; stainless-steel or coated body options; seat materials selected for the fluid | Corrosive chemicals, water treatment, and selected acids or alkalis after compatibility review | API 609 or EN 593 as applicable; verify chemical compatibility, permeation, temperature limits, and lining construction |
| Actuated and automated valve packages | Butterfly valve supplied with a manual gearbox, electric actuator, or pneumatic actuator | Size and pressure depend on the underlying valve; actuator selection depends on torque, operating conditions, and safety factor | Valve materials and seat options vary; actuator packages may include position indicators, solenoids, limit switches, or positioners | Remote isolation, process control, water and wastewater plants, and automated utility systems | Valve product standard plus applicable actuator, electrical-area, ingress-protection, and control-system requirements |
| Before selection, verify the exact pressure-temperature rating, end-to-end dimensions, face-to-face standard, leakage class, material certificates, testing requirements, and suitability for the process medium. Product ranges and certifications vary by supplier and model. |