Working principle
The low temperature ball valve is generally used in the case where the medium temperature is below -40 ℃, and the valve flap is automatically opened and closed depending on the flow of the medium itself, so as to prevent the medium from flowing back.
Features
1. The structure of opening a pressure relief hole on the valve core is adopted;
2. The gasket is made of ceramic filling material with stable sealing;
3. The valve body is light and small in size. In order to reduce the heat loss of the valve body, especially to ensure the use of the valve under ultra-low temperature, the valve body is specially designed to be light in weight and small in size;
4. The long-axis valve has a valve through which low-temperature fluid flows. It adopts the form of a long valve stem, which can avoid the effect of external heat and keep the gland at normal temperature to prevent the performance of the cover seal from being reduced. This length is the optimum length obtained by calculation and experimentation.
Application advantages
1. The fluid resistance is small. The ball valve has the smallest fluid resistance among all valves. Even the reduced diameter ball valve has a relatively small fluid resistance;
2. The switch is fast and convenient. As long as the valve stem rotates 90°, the ball valve completes the full opening or full closing action, and it is easy to realize rapid opening and closing;
3. Good sealing performance. The sealing ring of the ball valve seat is generally made of elastic materials such as polytetrafluoroethylene, which is easy to ensure the sealing, and the sealing force of the ball valve increases with the increase of the medium pressure;
4. Stem seal is reliable. When the ball valve is opened and closed, the valve stem only rotates, so the packing seal of the valve stem is not easy to be damaged, and the sealing force of the reverse seal of the valve stem increases with the increase of the medium pressure;
5. The opening and closing of the ball valve only rotates 90°, so it is easy to realize automatic control and remote control. The ball valve can be equipped with pneumatic devices, electric devices, hydraulic devices, gas-liquid linkage devices or electro-hydraulic linkage devices;
6. The ball valve channel is flat and smooth, and it is not easy to deposit the medium, and the pipeline can be passed through the ball.
Maintenance
1. Check whether there is ice in the valve body, if so, please remove any ice in the valve body, and then operate the valve;
2. Use a manual or pneumatic grease gun to fill the valve cleaning solution, and operate the valve after 10-20 minutes to discharge the sewage in the valve discharge nozzle;
3. Check the valve stem packing, intermediate flange and other parts for leakage;
4. If there is leakage in the valve stem, please check whether the valve has a valve stem grease injection structure, if so, slowly inject the valve sealing grease and stop filling;
5. The internal leakage treatment of the low temperature ball valve has been cleaned up, and the main solution is activity. Supplementing sealing grease is an auxiliary means;
6. When the valve is completely closed, the internal leakage inspection and treatment of the low temperature ball valve should be carried out as far as possible;
The operation of the cold valve should open and close as completely as possible, and the valve that cannot be opened and closed should be moved as much as possible.
Post time: Mar-08-2022