The ball valve is mainly used to cut off or connect the medium in the pipeline, and can also be used for fluid regulation and control. Compared with other valves, the pneumatic O-ring ball valve has the following advantages:
1. The fluid resistance is small, and the ball valve is one of the valves with small fluid resistance. Even the reduced diameter ball valve has relatively small fluid resistance.
2. The thrust bearing reduces the friction torque of the valve stem, which can make the valve stem operate stably and flexibly for a long time.
3. The sealing performance of the valve seat is good. The sealing ring made of elastic materials such as polytetrafluoroethylene is easy to seal, and the sealing capacity of the ball valve increases with the increase of the medium pressure.
4. The valve stem seal is reliable. Because the valve stem only operates as if it is rotating rather than lifting, the packing seal of the valve stem is not easy to be damaged, and the sealing capacity increases with the increase of the pressure of the medium.
5. Due to the good self-lubricating property of materials such as polytetrafluoroethylene and small friction loss with the ball, the service life of the ball valve is long.
6. The lower mounted valve stem and the convex step at the head of the valve stem prevent the valve stem from ejecting. If the valve stem seal is damaged due to fire, metal contact can also be formed between the convex step and the valve body to ensure the valve stem sealing.
7. Anti static function: set a spring between the ball, valve stem and valve body, and the pneumatic O-ring ball valve can lead out the static electricity generated during the switching process.

First, let's understand the lining of the electromagnetic flowmeter sensor
One of the basic conditions for the operation of the electromagnetic flowmeter is that the normal current of the inner wall of the measuring pipe is zero except at the electrode. This requires measuring the pipe wall insulation, which can protect the induced aerodynamic force from being short circuited by the metal pipe. Therefore, the inner wall of the conductive metal measuring pipe and the end face of the flange are lined with insulating linings. At the same time, the insulating lining also enables it to have corrosion resistance, wear resistance and other properties, Here, polytetrafluoroethylene is used as the insulating lining material. Generally, the lining materials include polytetrafluoroethylene, rubber, PVC, polyurethane rubber, industrial ceramics, etc. The polytetrafluoroethylene used here has very stable chemical properties and is resistant to boiling hydrochloric acid, sulfuric acid, aqua regia and concentrated alkali.