PT Putian D343H Triple Eccentric Hard Seal Butterfly Valve

Zhejiang Putian triple eccentric butterfly valves can be selected for applications involving two-position regulation, constricted underground channels, low noise, cavitation and vaporization phenomena, minor atmospheric leakage, and abrasive media.

Under special working conditions such as throttling regulation, stringent sealing requirements, severe wear, or low temperature (cryogenic) environments, specially designed triple or double eccentric butterfly valves with metal sealing and regulation devices are required.

Zhejiang Putian triple eccentric butterfly valves are suitable for applications requiring complete sealing, zero gas test leakage, high service life, and operating temperatures between -10°C and 150°C. They are used in freshwater, sewage, seawater, saline water, steam, natural gas, food, oil, various acids and alkalis, and other pipelines.

Zhejiang Putian soft-sealed eccentric butterfly valves are suitable for bidirectional opening and closing as well as regulation in ventilation and dust removal pipelines. They are widely used in gas pipelines and water channels in metallurgical, light industry, electric power, and petrochemical systems.

Zhejiang Putian triple eccentric metal-to-metal line-sealed double eccentric butterfly valves are suitable for urban heating, gas supply, water supply, and other pipelines carrying gas, oil, acids, alkalis, etc., serving as regulation and throttling devices.

Zhejiang Putian triple eccentric metal-to-metal face-sealed triple eccentric butterfly valves, in addition to being used as program control valves in large-scale pressure swing adsorption (PSA) gas separation units, are also widely used in petroleum, petrochemical, chemical, metallurgical, and electric power industries.

Working principle of Zhejiang Putian triple eccentric metal hard-sealed butterfly valve: In a typical triple eccentric metal-sealed butterfly valve, besides the two eccentrics of the valve stem and disc, the sealing surfaces of the disc and seat are shaped like a tapered frustum (this is the so-called third eccentricity). When the valve closes, the disc is pushed forward due to eccentricity, avoiding friction between the disc and seat during the closing process. The disc directly presses against the seat, ensuring the valve's service life.

Additionally, due to the elasticity of the sealing ring (whether mounted on the seat or disc) and a small gap between the protrusion inside the elastic ring and the ring itself allowing slight displacement, the elastic sealing ring can automatically move to a uniformly stressed position when the valve closes under the closing force. Combined with slight deformation of the elastic ring, the sealing ring at the seat is evenly stressed, achieving a sealed state.

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

With the continuous development of modern工艺 technology and materials, the application range of Zhejiang Putian butterfly valves has far exceeded the past,几乎可以取代大部分的传统阀门, widely applicable across various industrial fields. Particularly, triple eccentric metal-sealed butterfly valves have attracted significant attention.

Since the closing of triple eccentric butterfly valves, like gate valves, is achieved through torque, higher closing torque results in better seat sealing performance. Hence, some refer to triple eccentric butterfly valves as 90° rotating gate valves. In major factory overhauls, triple eccentric butterfly valves are increasingly replacing gate valves. For this reason, some manufacturers produce triple eccentric butterfly valves with the same length as gate valves and term them triple eccentric gate valves.

As the number of eccentrics in Zhejiang Putian valve discs increases, the disc thickness also increases, leading to higher fluid flow resistance through the triple eccentric butterfly valve. With an increase in the number of eccentrics, the valve's performance also changes significantly.

Comparison of four different structural butterfly valves shows that triple eccentric butterfly valves can generate a larger pressure drop and can be used as control valves. The pressure drop of fluid flowing through the valve increases with the number of eccentrics. However, compared to some non-butterfly valves, the pressure drop of triple eccentric butterfly valves is relatively small. As the number of eccentrics changes, the seat sealing performance also varies, with triple eccentric butterfly valves offering excellent seat sealing. Increasing the number of eccentrics reduces the torque required for valve opening and closing, making the torque required for triple eccentric butterfly valves much lower than that for other types.

With changes in the number of eccentrics, the temperature-pressure rating range and applicable temperature range of butterfly valves also change significantly. The applicable temperature and pressure rating range of triple eccentric butterfly valves surpasses that of other types.

Advantages of triple eccentric butterfly valves: Excellent shut-off performance. Triple eccentric metal-sealed butterfly valves utilize torque to shut off the valve, ensuring superior sealing performance at the seat, hence被称为零泄漏阀. Solid particles or contaminants in the medium have no significant impact on the shut-off performance of triple eccentric metal-sealed butterfly valves because the high medium velocity near closure prevents accumulation of debris at the seat.

Features of metal hard-sealed butterfly valves:

1. The disc sealing ring of Zhejiang Putian triple eccentric multi-layer metal hard-sealed butterfly valves consists of laminated soft and hard metal sheets, combining the advantages of both metal and elastic sealing. It offers excellent sealing performance under 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 from each bushing. This structure prevents wear and sticking, thereby extending service life.

3. The three-dimensional eccentric structure ensures almost no friction between the seat and disc, causing minimal damage to internal components during closure. This design significantly enhances valve performance in use and features a sealing function that tightens with closing.

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

5. Compact structure, low opening and closing torque, flexible, labor-saving, and convenient operation, unaffected by medium pressure高低, with reliable sealing performance. Can be used for both isolation and regulation.

Eccentricity 1: The valve shaft is located behind the seat axis, allowing the seal to fully and tightly contact the entire seat circumference.

Eccentricity 2: The valve shaft centerline 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 shaft centerline, eliminating friction during closing and opening, and achieving uniform compression sealing around the entire seat.