Balls of fixed ball valve are supported by upper and lower axises. The acting force of the medium passes from the floating seat to the upper and lower axises of balls. Torque will be reduced greatly when operating valves. Fixed ball valve is widely used. It is developed to endure high temperature and high pressure, be of large caliber, superior seal and long use. It is especially applied to oil and gas pipelines, oil refining cracker and nuclear industry more widely used.