The ball of the floating ball valve is floating, and under the pressure of the medium, the ball can produce a certain displacement and be tightly pressed against the sealing ring at the outlet end, ensuring the sealing of the outlet end and belonging to single-sided forced sealing. The ball of a fixed ball valve is fixed and does not move under pressure. Therefore, in the design, the two sealing rings should have sufficient pre tightening force to ensure sealing, which belongs to double-sided forced sealing. Usually, thrust or sliding bearings are installed on the upper and lower valve stems that are integrated with the ball. When designing a floating ball valve, special consideration should be given to whether the sealing ring material can withstand the medium load of the ball. Because the load of the working medium borne by the sphere is all transmitted to the outlet sealing ring, this floating ball structure is widely used in medium and low pressure ball valves. In addition, the design should also consider the large torque required for operating large-diameter ball valves.

Floating ball valves are commonly used in medium and low pressure small-diameter pipelines such as water and gas, such as shut-off valves in general industrial systems. Fixed ball valves are used in high-pressure and large-diameter applications such as petrochemicals, long-distance pipelines, and power, such as Class 1500 and above pipeline ball valves.

Floating ball valves have a simple structure and low cost, but are limited by pressure and diameter; Fixed ball valves are suitable for more demanding working conditions by optimizing their sealing and support structures, but with higher costs and technical requirements. Design selection should comprehensively consider pressure, diameter, medium characteristics, and maintenance requirements.