There are various forms of filling heads required by the filling process. According to the movement form of the movable part in the filling valve of the filling machine, they can mainly be divided into three types:

1. Single sliding valve

There is a movable part in the valve body, which makes a round trip in a straight line relative to the stationary part when opening and closing the valve. According to the method of opening and closing the fluid passage before and after the movement of the movable part, it can be divided into two types:

① End face type:

The fluid passage is opened or closed by moving the end face of the block.

② Cylindrical type:

It is opened and closed by whether the channels on the cylindrical surface of the moving block are connected to the channels of the stationary part (valve seat).

2. Rotary valve

The movable part in the valve body rotates and swings back and forth one or more times relative to the stationary part when opening and closing the valve. At the two limit positions of the swing, the opening and closing of the fluid passage is completed by whether the holes on the movable part are aligned with those on the stationary part. According to whether the relative rotation surface is along the cylindrical surface (or conical surface) or along the plane, it can be further divided into the following two forms:

① Column type (or cone type)

This type of valve has holes at a certain Angle on the cylindrical surface (or cone) of the movable part - the plug, which correspond respectively to the holes of the immovable part - the valve seat.

② Disc type

This type of valve has holes at a certain Angle on the end plane of its movable part, the valve cover, which correspond respectively to the holes of the movable part, the valve seat.

3. Multi-slide valve

There are several movable parts in the valve body that move in a straight line to complete the opening and closing of the liquid or gas path. According to the method of controlling the opening of the liquid valve, it can be further divided into the following two types:

① Pneumatic type

The gas valve opens first under mechanical action. When the gas inside the bottle is filled to the same pressure as the gas phase space in the storage tank, the upward force generated by the gas pressure inside the bottle is just enough to overcome the sealing force of the liquid valve, and then the liquid valve will open automatically.

② Mechanical type

The gas valve opens first under mechanical action. After a certain period of time, the liquid valve still opens under mechanical action.