Features of the triple-eccentric multi-layer hard-sealed butterfly valve product

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　　With the rapid development of industrial technology, the valve industry has set stricter requirements, especially for hard-sealed butterfly valves operating in low-temperature environments. In addition to meeting the performance standards of ordinary valves, these valves must also ensure reliability in sealing under low temperatures, exhibit flexibility, and satisfy other specific requirements. 　　Hard-sealed butterfly valves feature a compact structure, small size, and light weight; compared to gate valves of the same size, they can reduce space requirements by 50% to 40%. They also exhibit low fluid resistance and enable rapid opening and closing. However, in some Chinese low-temperature equipment used in the chemical industry, such as natural gas liquefaction equipment, air separation equipment, and pressure swing adsorption equipment, globe valves or gate valves are predominantly used, with very few hard-sealed butterfly valves. The main reasons analyzed are that metal hard-sealed butterfly valves have inferior sealing performance in low-temperature conditions compared to other types of valves, as well as issues with their design; these factors lead to fluid leakage. Such leakage severely affects the safety and proper operation of these low-temperature devices, and they fail to meet the requirements of such applications. 　　With the continuous development of low-temperature equipment in China, the requirements for valves to be used in low-temperature environments are increasing. To meet the needs of market development, metal hard-sealed butterfly valves have been structurally improved by introducing a triple-eccentric sealing design, which enhances their sealing performance and enables them to operate effectively in both high- and low-temperature conditions. 　　The series of triple-eccentric multi-layer hard-seal butterfly valves are long-life, energy-saving butterfly valves. Its structure is designed based on the three-dimensional core-winding principle; the valve seat features a multi-layered design that combines hard and soft sealing elements, offering excellent precision in manufacturing and advanced production techniques. This product consists of main components such as the valve body, butterfly disc, multi-layer valve seat, valve stem, and actuation mechanism. Therefore, it is widely used in pipelines for corrosive media such as those in the metallurgy, power, petroleum, chemical industries, as well as in air, gas, flammable gases, and water supply and drainage systems. Features of the three-eccentric multi-layer hard-seal flanged butterfly valve: Since this butterfly valve is designed using the principle of three-dimensional eccentricity, the spatial movement path of the sealing surfaces is optimized; there is no friction or interference between the sealing surfaces. Coupled with the appropriate selection of sealing materials, the valve’s sealing performance, corrosion resistance, high-temperature tolerance, and wear resistance are all reliably ensured. Its main features are as follows: 1. It requires a low starting torque, is flexible and convenient, and saves effort and energy. 　　2. The three-dimensional core structure ensures that the butterfly valve closes more tightly, providing reliable sealing performance with no leaks. 　　3. High pressure resistance, corrosion resistance, wear resistance, and a long service life, etc. Principle of the three-eccentric multi-layer hard-seal flanged butterfly valve: When the valve is opened, the butterfly disc comes into contact with the valve seat for an instant at the time of closing; thanks to the eccentricities 1 and 2 of the butterfly disc, it quickly separates from the valve seat, which reduces wear on the sealing surfaces. As a result, the frictional torque is low, allowing for smooth operation of the valve. The eccentric conical surface 3 allows the butterfly disc to pass through the inner hole of the valve seat when the valve is opened or closed, thereby achieving a contact seal. Furthermore, the rotational radius of the conical butterfly valve disc is greater than that at the contact point of the sealing pair; as a result, the disc closes more tightly as the valve is closed, enabling self-locking and preventing the disc from moving beyond its proper position.