Spherical valve (ball valve) was introduced in the 1950s, with the ball valve with the rapid development of science and technology, production technology and product structure of continuous improvement, in a short period of 40 years, has rapidly developed into a major valve class. In the Western industrial developed countries, the use of ball valves is constantly rising year by year, in China, ball valves are widely used in petroleum refining, long-distance pipelines, chemical, paper, Pharmaceutical, water conservancy, electricity, municipal, steel and other industries, in the national economy occupies a pivotal position. It has the action of rotating 90 degrees, the plug body is a sphere, there is a circular through hole or passage through its axis. Ball valve in the pipeline is mainly used to cut, distribute and change the flow direction of the medium, it only needs to rotate 90 degrees of operation and a very small rotation torque can be closed tight. Ball valve is most suitable for switching, cutting valve use, V-type ball valve. Electric valve In addition to attention should be paid to the pipeline parameters, should pay special attention to its use of the environmental conditions, because the electric valve in the electric device is a mechanical and electrical equipment, its use of the State is greatly affected by its use of the environment. In general, electric ball valves and butterfly valves should be used with special attention in the following environments.
