Detailed explanation of the selection and application of butterfly valve sealing structure

Technical features of multi-level sealed butterfly valves

For example, in urban water supply systems, it can completely prevent water leakage; in chemical production processes, it can effectively prevent the leakage of toxic and harmful substances; in the food and pharmaceutical fields, it can meet the hygiene-level usage requirements. However, it should be noted that the elastic sealing material used is a wear-prone component. Under frequent opening and closing operations or in the presence of solid particles, its service life will be significantly shortened. Therefore, regular inspection and replacement are required.

The performance advantages of hard-to-hard sealing butterfly valves

The hard-to-hard sealing structure adopts a full-metal sealing design. The sealing surfaces of the valve seat and the butterfly plate are made of specially hardened metal materials. Common surface treatment processes include Stellite alloy overlay, tungsten carbide spraying, plasma nitriding, etc. The surface hardness can reach above HRC60. This structure achieves complete sealing through precise processing of the metal surface, with tolerances typically controlled within 0.01 millimeters. Although theoretically, this absolute sealing performance is not as good as that of soft sealing structures, it shows excellent stability in high-temperature and high-pressure environments. This type of valve has extremely excellent high-temperature resistance. Under high-temperature working conditions, it can withstand temperatures exceeding 600℃ and has a pressure rating of PN100 or higher. Its core advantage lies in its reliability in extreme conditions: in high-temperature steam pipelines, there will be no problem of softened and failed sealing materials; in gas or powder conveying systems containing solid particles, the hardened surface has extremely strong corrosion resistance; in thermal oil circulation systems, the sealing material will not expand or deform. In addition, the full-metal structure ensures its service life is typically 3 to 5 times that of soft-sealing valves, making it particularly suitable for scenarios that require frequent operation or difficult maintenance.