Sanitary Butterfly Valve is used to control solid materials. They are usually used as discharge valves at the bottom of water tanks (such as cement water tanks, stone powder water tanks, etc.) for discharge and quick cut-off. Because most dust materials contain large or small particles, there is no doubt that the sealing surface of the valve will be worn. Improper selection will greatly reduce the service life of the valve, or quickly cause internal leakage of the valve, affecting continued use. Let the editor take you to understand it.
For the batching weighing system, the entire batching process is automatically controlled by PLC. The discharge valve of the batching trolley is a pneumatic three-eccentric butterfly valve, and the medium is relatively fine stone powder. After a period of time, the valve leaked, causing the stone powder to leak onto the workbench in piles because the medium is very fine and a little sticky. Although the quantitative trolley is equipped with a vibration motor, there is still a lot of material attached to the upper wall of the tank and the valve parts. When the valve is closed, it sticks to the sealing surface, so the valve cannot be completely closed and reinstalled, which will cause leakage. Over time, the sealing surface wears very seriously, and even grooves appear.
In the PLC program, the vibration time of the motor is extended, and the valve is closed after the material is vibrated as much as possible; the zero point of the weighing instrument has been adjusted, and it will display zero after all the materials are taken out. At this time, the PLC sends a signal to close the valve; the triple eccentric butterfly valve is replaced by a double eccentric elastic hard seal butterfly valve (the centerline seal rubber butterfly valve can also be used. Considering that there are occasional large particles in the material, the rubber seal may not be durable-if it is a fine powder without particles, a soft seal butterfly valve can be considered), because the valve seat of the triple eccentric butterfly valve is an inclined sealing surface, that is, a surface seal, so the material is easy to accumulate on the sealing surface and cannot be discharged quickly, but the single eccentric or double eccentric butterfly valve does not have this disadvantage. Even if there is little material on the sealing surface, it will be scraped off by the valve plate when the valve is closed. Good sealing, strong and durable sealing surface.

Other factors need to be considered in the powder material system of the pneumatic butterfly valve, such as: when the material is placed in the trolley from above, the material cannot directly hit the valve plate of the valve (the impact force will also prevent the valve from closing tightly) and the static pressure of the material should not exceed the design bearing pressure of the pneumatic butterfly valve, etc.
The difference between a control valve and an ordinary manual valve is that it cannot be regarded as an isolated component, but must be regarded as part of the entire automatic control system. Many problems in the use of control valves are not selected, and configuration problems are caused by the user's lack of understanding of the control valve, which leads to the inability of the control valve to be debugged and used in conjunction with the control system. As long as the key to the problem can be found, the valve can be correctly selected and the control valve can be debugged during the system debugging stage, which can greatly reduce the failure rate and ensure the long-term stable operation of the automatic control system.