What factors depend on the working conditions of sanitary valves?
What factors depend on the working conditions of sanitary valves? The working conditions of sanitary valves depend on many factors, among which the main ones are: working pressure of the medium, working temperature, characteristics of the medium, changes in pressure and temperature, driving mode, installation position of the sanitary valve, maintenance period, and sanitary valve The working conditions depend on many factors, including the working pressure of the medium, the working temperature, the characteristics of the medium, the change of pressure and temperature, the driving mode, the installation position of the valve, the maintenance period, the need for pressure relief in the middle cavity, With or without fireproof structure, with or without anti-static structure, whether grease injection is required, whether the sanitary valve is buried in the ground, whether it is installed on land or offshore, whether it is adjusted or opened and closed, and the environmental conditions of valve operation. Generally speaking, the higher the working pressure and temperature of the sanitary valve, the worse the working conditions will be when installed at sea. Therefore, in order to ensure the safety and reliability of the valve, it is necessary for the pressure-bearing parts and pressure-controlling parts of the valve to have sufficient strength , Especially the various properties of the material at high temperature and low temperature, such as thermal strength, oxidation resistance, thermal stability, impact toughness of the material under low temperature conditions, etc. The sealing surface material must also have good scratch resistance, abrasion resistance, corrosion resistance, erosion resistance, etc., because the high pressure medium flows through the dense surface very quickly and the erosion is serious. In order to ensure the packing and gaskets For sealing performance, different forms and materials must be selected according to the characteristics of the medium, temperature and working pressure. As for valves that work at low and ultra-low temperatures, it must be ensured that the material should have sufficient low-temperature impact toughness. For valves that work in corrosive media, all pressure-bearing parts and pressure-controlling parts (including gaskets and packing) that are in contact with the media should have sufficient stability against the chemical action of the medium, otherwise the valve is not resistant to corrosion and has a short life. Meet the requirements for use. Pressure and temperature fluctuations will cause poor sealing conditions for the connecting flange, because the connecting bolts and gaskets will be deformed when the working pressure and working temperature are high. When the working pressure and working temperature decrease, the gasket loses its sealing performance due to insufficient pressing force. Such periodic fluctuations also affect the material properties of the parts. Therefore, the fluctuations in the working pressure and the working condition have an impact on the working conditions of the valve. It is extremely unfavorable. Each driving device has its own force characteristics, which are related to the different specific pressure values u200bu200bon the sealing surface, and also related to the stress of the valve stem, valve stem nut and other parts. When the electric device is closed to the end ': Impact load will be caused on the sealing surface, especially for globe valves. The hydraulic device is usually a relatively stable load, and the pneumatic device also has an impact load on the shut-off valve. In a safety valve, when the disc returns to its seat, it will also have an impact on the sealing surface due to the action of the spring and the heavy hammer. The condition of the sealing surface is deteriorated, and the service life of the valve is affected to varying degrees. When sanitary valves are installed and used in the open, the working conditions are very poor. Because wind and rain are easy to rust, and sometimes even damage the lubrication, if dust and sand fall into the joints of the parts, it will accelerate the wear of the parts. If the valve is installed and used offshore, the working environment of the valve will be even worse. The valve as a whole is in the salt spray and will be eroded by chloride ions in the salt spray. The valve is easily corroded and loses its function. The selection of the valve material should consider the corrosion resistance of chloride ions, and at the same time should pay attention to the painting of the outer surface. If the valve is installed and used in the ground, a fully welded valve with an extension should be used to prevent the valve from being corroded by groundwater and mud and damaging the connecting parts and moving parts of the valve after being buried. In order to ensure the service life of sanitary valves, the structure of the valve and the materials of the main parts must be selected according to the working conditions, otherwise the service life of the valve will inevitably be reduced. At the same time, the maintenance of the valve should be strengthened during use. Such as regular removal of dirt, regular grease injection, regular maintenance, etc., to extend the service life of the valve.