Sealing performance of custom cut-off ball valves

Sealing performance is the core of the reliable operation of cut-off ball valves in extreme environments, especially in high temperature, high pressure or corrosive media environments. The sealing performance directly determines the service life and safety of the valve. In order to ensure that the valve can still maintain excellent sealing effect under these harsh conditions, the selection of sealing materials and structural design of custom cut-off ball valves need to be carefully optimized.

In high temperature environments, sealing materials must have excellent high temperature resistance. Ordinary sealing materials are prone to softening, aging and even failure at high temperatures, so special materials that can withstand high temperatures need to be selected. Graphite is a commonly used high-temperature sealing material. Because of its good heat resistance and self-lubricating properties, it can maintain a stable sealing effect at high temperatures. Metal sealing rings are also widely used in high temperature environments. Their high strength and heat resistance make them an ideal choice for high temperature conditions. For some special high temperature environments, modified high temperature elastomer materials, such as modified materials of polytetrafluoroethylene (PTFE), can also be used. These materials are not only resistant to high temperatures, but also have excellent chemical stability.

In high pressure environments, the design of the sealing structure is particularly important. A single sealing structure may not be able to completely prevent media leakage under high pressure, so a multiple sealing design is needed to enhance the sealing effect. The combination of metal seals and soft seals is a common high-pressure sealing solution. Metal seals can withstand higher pressures, while soft seals can make up for the shortcomings of metal seals in microscopic unevenness, thus forming a more reliable sealing barrier. This multiple sealing design can not only effectively prevent high-pressure media leakage, but also extend the service life of the valve.

For corrosive media environments, the selection of sealing materials needs to pay special attention to corrosion resistance. Ordinary sealing materials are easily corroded in corrosive media, resulting in seal failure. Materials with excellent corrosion resistance, such as fluororubber, polytetrafluoroethylene (PTFE) or ceramic materials are usually selected. Fluororubber is widely used in corrosive media environments such as strong acids and alkalis due to its excellent chemical corrosion resistance and temperature resistance. Polytetrafluoroethylene (PTFE) has become the preferred sealing material in many corrosive working conditions due to its extremely low friction coefficient and excellent corrosion resistance. Ceramic materials have also been used in some extremely corrosive environments due to their high hardness and corrosion resistance.