The ball valve is evolved from the plug valve. It has the same rotation of 90 degrees, except that the ball valve is a sphere with a circular through hole or passage through its axis. The ratio of the spherical and the channel should be the same, that is, when the ball rotates 90 degrees, the entrance and exit should all appear spherical, thus cutting off the flow. The ball valve only needs to be rotated 90 degrees of operation and a small turning torque can be closed tightly. The fully equal body cavity provides a very small, straight passage for the medium.

It is generally believed that the ball valve is most suitable for direct opening and closing use, but the recent development of the ball valve has been designed so that it has a throttle and control the flow of use. The main features of the ball valve itself is compact, easy to operate and repair, suitable for water, solvents, acids and natural gas and other general working medium, but also for poor working conditions such as oxygen, hydrogen peroxide, methane and ethylene. Ball valve body can be the whole, it can be modular.