Large-diameter Flange Double eccentric Butterfly valve
This is a large-diameter, industrial-grade butterfly valve. The valve body is constructed from cast steel and finished with a blue, anti-corrosive coating. It features a full-flange connection at both ends, with a series of bolt holes evenly spaced around the circumference of the flanges to meet the high-strength connection requirements of large-diameter industrial piping. The valve is equipped with a top-mounted worm gear actuator, which ensures effortless operation. The butterfly disc incorporates an internal grid-like reinforcement structure, which maintains high structural integrity while significantly reducing flow resistance.
Manufacturing Range
Size Range: DN50–DN4500; standard mass-produced models typically span DN50–DN2000, with ultra-large sizes available via custom order.
Pressure Rating: PN10–PN100 (equivalent to ASME Class 150–Class 600); standard operating range covers PN0.6–PN4.0 MPa.
Temperature Range: Carbon steel models support -29°C to 425°C; stainless steel models can be configured for -196°C to 650°C; specialized high-temperature versions can withstand up to 850°C.
Materials and Configurations: Valve bodies are available in carbon steel, various grades of stainless steel, duplex steel, and more. Connection options include flanged, wafer, butt-weld, and lug styles. Actuation methods include manual, worm gear, pneumatic, electric, and hydraulic systems.
Applicable Media: Suitable for water, steam, dust-laden flue gas, oils, and mildly corrosive fluids. With the use of specialized materials, the valves can also handle highly corrosive media, such as strong acids/alkalis or fluids with high chloride ion concentrations.
Design Features
Featuring a triple-offset metal-to-metal sealing design, the valve experiences virtually no frictional wear on the sealing surfaces during opening and closing. It utilizes a wedge effect to achieve a bi-directional, zero-leakage seal that becomes tighter as the valve is closed further.
The metal sealing interface is highly resistant to high temperatures and wear, making it suitable for demanding operating conditions—such as high-temperature steam, dust-laden flue gas, and various oils—with a service life significantly longer than that of standard soft-seated butterfly valves.
The large-diameter, truss-style disc design provides a generous flow area and minimal flow resistance, effectively serving both as a pipeline shut-off mechanism and a means for regulating high-volume flow.
Design Standards
Domestic Standards: GB/T 12238 defines the fundamental design and dimensional series for butterfly valves; GB/T 13927 establishes criteria for testing and evaluating shell strength and sealing performance; and HG/T 6353-2025 provides supplementary requirements for specialized performance and inspection in petrochemical applications.
International Standards: API 609 serves as the authoritative international manufacturing specification for butterfly valves in the petrochemical sector, covering the entire process—from design and materials to inspection requirements. ISO 5211 standardizes the top-flange connection dimensions for actuators, ensuring compatibility and interchangeability across different drive components.
Key Control Parameters: These standards specify critical design requirements—such as triple-offset geometric parameters, hard-sealing interface configurations, and blow-out-proof stem designs—while regulating the material selection for valve bodies, sealing surfaces, and fasteners. Comprehensive performance verification is mandated to ensure long-term, stable operation under high-temperature and high-pressure conditions.