D943H Triple Eccentric Flange Type Hard Seal Butterfly Valve

Zhejiang Putian Triple Eccentric Butterfly Valve can be selected for dual-position regulation, constricted channels, low noise, cavitation and vaporization phenomena, slight atmospheric leakage, and abrasive media.

Under special working conditions such as throttling regulation, strict sealing requirements, severe wear, or low temperature (cryogenic) environments, a specially designed triple or double eccentric butterfly valve with a metal sealing adjustment device should be used.

Zhejiang Putian Triple Eccentric Butterfly Valve is suitable for applications requiring complete sealing, zero gas test leakage, high service life, and operating temperatures between -10°C and 150°C. It can be used in freshwater, sewage, seawater, saline water, steam, natural gas, food, oil, various acids and alkalis, and other pipelines.

Zhejiang Putian Soft Seal Eccentric Butterfly Valve is suitable for bidirectional opening, closing, and regulation in ventilation and dust removal pipelines. It is widely used in gas pipelines and water channels in metallurgical, light industrial, power, and petrochemical systems.

Zhejiang Putian Triple Eccentric Metal-to-Metal Line Seal Double Eccentric Butterfly Valve is suitable for urban heating, gas supply, water supply, and other pipelines carrying gas, oil, acids, alkalis, etc., serving as a regulating and throttling device.

Zhejiang Putian Triple Eccentric Metal-to-Metal Face Seal Triple Eccentric Butterfly Valve, in addition to being used as a program control valve in large pressure swing adsorption (PSA) gas separation units, is also widely used in petroleum, petrochemical, chemical, metallurgical, power, and other industries.

Working principle of Zhejiang Putian Triple Eccentric Metal Hard Seal Butterfly Valve: In a typical triple eccentric metal seal butterfly valve, besides the two eccentrics of the valve stem and disc, the sealing surfaces of the disc and seat are conical (the third eccentricity). When the valve closes, the disc is pushed forward due to eccentricity, avoiding friction between the disc and seat during closure. The disc directly presses against the seat, ensuring long service life.

Additionally, the sealing ring (whether mounted on the seat or disc) of Zhejiang Putian valves has certain elasticity, and a small gap between the inner boss and the elastic ring allows slight displacement. During closure, the elastic sealing ring automatically moves to a uniformly stressed position under closing force. Combined with slight deformation of the elastic ring, the sealing ring at the seat achieves uniform stress and sealing.

Performance variations of triple eccentric metal hard seal butterfly valves with different eccentric structures: Traditionally, butterfly valves were considered suitable only for常温, low-pressure, and low-sealing-requirement applications.

With advancements in modern technology and materials, Zhejiang Putian butterfly valves are now used far beyond their traditional scope, almost replacing most conventional valves and widely applied across various industries. The triple eccentric metal seal butterfly valve is particularly noteworthy.

Since the closure of a triple eccentric butterfly valve, like a gate valve, is torque-driven, higher closing torque results in better seat sealing. Hence, it is sometimes called a 90° rotating gate valve. In major factory maintenance, triple eccentric butterfly valves increasingly replace gate valves. Some manufacturers produce triple eccentric butterfly valves with the same length as gate valves, dubbing them triple eccentric gate valves.

As the number of eccentrics in Zhejiang Putian valves increases, the disc thickness also increases, raising fluid flow resistance. Performance changes significantly with the number of eccentrics.

Comparison of four different butterfly valve structures shows that triple eccentric butterfly valves can generate high pressure drops, making them suitable as control valves. Pressure drop across the valve increases with the number of eccentrics, but compared to some non-butterfly valves, it remains relatively low. Seat sealing performance changes with eccentricity; triple eccentric valves offer excellent sealing. Increased eccentricity reduces the torque required for opening and closing, making triple eccentric valves much easier to operate than other types.

With changes in eccentricity, the temperature-pressure rating and applicable temperature range of butterfly valves also vary significantly. Triple eccentric butterfly valves have broader temperature and pressure ratings compared to other types.

Advantages of triple eccentric butterfly valves: Excellent shut-off performance. The triple eccentric metal seal butterfly valve uses torque to achieve closure, ensuring superior seat sealing, often referred to as zero leakage. Solid particles or contaminants in the medium have minimal impact on shut-off performance because high fluid velocity near closure prevents accumulation at the seat.

Features of metal hard seal butterfly valves:

1. The disc sealing ring of Zhejiang Putian triple eccentric multi-layer metal hard seal butterfly valve is a laminated metal sheet, combining the advantages of metal and elastic sealing. It provides excellent sealing performance at both low and high temperatures.

2. Bushings are installed at the upper and lower parts of the valve stem, with minimal wear and friction resistance. This structure prevents wear and sticking, extending service life.

3. The three-dimensional eccentric structure ensures almost no friction between the seat and disc, minimizing internal damage during closure. It enhances valve performance and features a sealing function that tightens with closure.

4. The valve body sealing surface is made of welded alloy steel or Stellite hard alloy, offering wear, erosion, and corrosion resistance, ensuring long service life.

5. Compact structure, low operating torque, flexible, labor-saving, and convenient operation. Sealing performance is reliable regardless of medium pressure. It can be used for both on/off and regulation.

Eccentricity 1: The valve axis is behind the seat axis, allowing the seal to fully and tightly encircle the entire seat.

Eccentricity 2: The valve axis is offset from the pipeline and valve centerline, avoiding interference during valve opening and closing.

Eccentricity 3: The seat cone axis is offset from the valve axis, eliminating friction during opening and closing, and achieving uniform compression sealing around the entire seat.