The ash discharge ball valve evolved from the globe valve. It has the same 90 degree rotation lifting action, but the difference is that the plug body is a sphere with a circular through-hole or channel passing through its axis. The ratio of the sphere to the channel opening should be such that when the sphere rotates 90 degrees, it should all appear spherical at the inlet and outlet, thereby intercepting the flow.  

The ash discharge ball valve evolved from the globe valve. It has the same 90 degree rotation lifting action, but the difference is that the plug body is a sphere with a circular through-hole or channel passing through its axis. The ratio of the sphere to the channel opening should be such that when the sphere rotates 90 degrees, it should all appear spherical at the inlet and outlet, thereby intercepting the flow.  

1、 Function

The working principle of the ash discharge ball valve is to rotate the valve to make it smooth or blocked. Pneumatic ball valve switches are lightweight, small in size, can be made into large diameters, reliable in sealing, simple in structure, easy to maintain, and the sealing surface and spherical surface are often in a closed state, which is not easily eroded by the medium. They are widely used in various industries.  

Pneumatic ash discharge ball valve and plug valve belong to the same type of valve, except that its closing element is a ball that rotates around the center line of the valve body to achieve opening and closing.  

Pneumatic ash discharge ball valves are mainly used in pipelines to cut off quickly, distribute and change the flow direction of the medium. Pneumatic ball valve is a new type of valve widely used in recent years.  

2、 Advantages

1. The fluid resistance is small, and its resistance coefficient is equal to that of a pipe segment of the same length.  

2. Simple structure, small size, and light weight.  

3. Tight and reliable. Currently, plastic is widely used as the sealing surface material for ball valves with good sealing performance, and it has also been widely used in vacuum systems.  

4. Easy to operate, quick opening and closing, only need to rotate 90 ° from fully open to fully closed, making it convenient for remote control.  

5. Easy to maintain, pneumatic ball valve has a simple structure, and the sealing ring is generally movable, making disassembly and replacement relatively convenient.  

When fully open or fully closed, the sealing surfaces of the ball and valve seat are isolated from the medium, and when the medium passes through, it will not cause erosion of the valve sealing surface.  

7. It has a wide range of applications, with diameters ranging from a few millimeters to several meters, and can be used from high vacuum to high pressure. Pneumatic ash discharge ball valves have been widely used in various sectors such as petroleum, chemical, power generation, papermaking, atomic energy, aviation, rockets, as well as in people's daily lives.  

3、 Classification

（1） Floating pneumatic ball valve

The ball of the pneumatic ash unloading ball valve is floating, and under the pressure of the medium, the ball can produce a certain displacement and press tightly against the sealing surface at the outlet end, ensuring the sealing of the outlet end.  

The structure of the pneumatic ash unloading ball valve is simple and has good sealing performance, but the ball bears all the load of the working medium transmitted to the outlet sealing ring. Therefore, it is necessary to consider whether the sealing ring material can withstand the working load of the ball medium. This structure is widely used for medium and low pressure ball valves.  

（2） Fixed pneumatic ball valve

The ball of a pneumatic ball valve is fixed and does not move under pressure. Fixed ball valves are equipped with floating seats, which move when subjected to medium pressure, causing the sealing ring to press tightly against the ball to ensure sealing. Usually, bearings are installed on the upper and lower shafts of the sphere, with a small operating torque, suitable for high-pressure and large-diameter valves.  

In order to reduce the operating torque of pneumatic ball valves and increase the reliability of sealing, oil sealed ball valves have emerged in recent years. They inject special lubricating oil between the sealing surfaces to form an oil film, which enhances sealing performance and reduces operating torque, making them more suitable for high-pressure and large-diameter ball valves.  

（3） Elastic ball pneumatic ball valve

The ball of the pneumatic ash unloading ball valve is elastic. The ball and valve seat sealing ring are both made of metal materials, and the sealing pressure ratio is very high. Relying on the pressure of the medium itself cannot meet the sealing requirements, and external force must be applied. This type of valve is suitable for high temperature and high pressure media.  

An elastic sphere is obtained by creating an elastic groove at the lower end of its inner wall. When closing the channel, use the wedge-shaped head of the valve stem to expand the ball and press it against the valve seat to achieve sealing. Release the wedge-shaped head before rotating the sphere, and the sphere will return to its original shape, creating a small gap between the sphere and the valve seat, which can reduce friction and operating torque on the sealing surface.  

Pneumatic ash discharge ball valves can be divided into straight through, three-way, and right angle types according to their channel positions. The latter two types of ball valves are used for distributing media and changing the flow direction of media.