Ball valve – "relative" pipeline valve. Its the locking element – a spherical shape, hence the definition of "ball". This is a modern, progressive type valves having the most extensive application in many areas of industry, urban communications, pipelines that transport natural gas, oil, among other areas. It would seem, ball valves began to find its broad application with respect to recently, however, design them not so new – it more than a hundred years. But before manufacturing techniques do not provide a dense overlap of passage passed through the pipeline environment. This is a case where a simple and very productive idea was lacking for the practical implementation of decent materials. When were in the industry and came to Valve Teflon, synthetic rubber, which provided a really tight fit of the saddle shell to the surface of a metal ball stoppers – it was then that ball valves have finally widespread. These materials ensure a tight seal and substantially reduced the effort to crane controls. True, the temperature is transmitted by the medium should not exceed 200 degrees. The reason for this is that the seat shell run rings made of plastic, which allows easy, leak and smooth rotation of the ball tube. Gate that is movable component of ball valves, is a spherical tube, along which the through hole intended for the passage of the medium. Most-diameter round hole tube to the inner diameter of the pipe. This is called a full bore ball valve. When passing through the valve open fully, hydraulic losses of the working environment is very small, which is advantageous in times, features ball valves from other types of valves and makes them the main shut-off device for linear sections of main gas pipelines. However, if the control valve is particularly important to consider factors such as Reduction in size, as well as torque is applied another type of ball valves – narrowed. How is the control of ball valves? For small diameters – by hand. At large – are used electric or hydraulic actuators.