1. The ball valve is evolved from the plug valve. Its opening and closing part acts as a sphere, which uses the sphere to rotate 90 degrees around the axis of the valve stem to achieve the purpose of opening and closing.
2. Ball valve function
The ball valve is mainly used for cutting off, distributing and changing the flow direction of the medium in the pipeline. The ball valve designed as a V-shaped opening also has a good flow adjustment function.
The ball valve is not only simple in structure, good in sealing performance, but also small in size, light in weight, low in material consumption, small in installation size, and small in driving torque within a certain nominal passage range. It is simple to operate and easy to achieve rapid opening and closing. One of the fastest growing valve varieties in more than ten years. Especially in developed countries such as the United States, Japan, Germany, France, Italy, West, and Britain, the use of ball valves is very extensive, and the variety and quantity of use continue to expand. Life, excellent regulating performance and multi-functional development of a valve, its reliability and other performance indicators have reached a higher level, and have partially replaced gate valves, stop valves, and regulating valves.
With the advancement of ball valve technology, in the foreseeable short time, there will be more extensive applications in oil and gas pipelines, oil refining and cracking units, and the nuclear industry. In addition, ball valves will also become one of the leading valve types in large and medium-sized calibers and low- and medium-pressure fields in other industries.
3 advantages of ball valve
Has the lowest flow resistance (actually zero)
Because it will not get stuck during work (when there is no lubricant), it can be reliably applied to corrosive media and low-boiling liquids.
In a larger pressure and temperature range, a complete seal can be achieved.
It can realize fast opening and closing, and the opening and closing time of some structures is only 0.05-0.1s to ensure that it can be used in the automation system of the test bench. When opening and closing the valve quickly, there is no shock in operation.
Ball valve structure
The working medium is reliably sealed on both sides.
When fully open and fully closed, the sealing surface of the ball and the valve seat is isolated from the medium, so the medium passing through the valve at high speed will not cause erosion of the sealing surface.
With compact structure and light weight, it can be considered as the most reasonable valve structure for cryogenic media systems.
The valve body is symmetrical, especially when the valve body structure is welded, which can well withstand the stress from the pipeline.
The closing piece can withstand the high pressure difference when it is closed.
The ball valve with a fully welded body can be directly buried in the ground, so that the internal parts of the valve are not corroded, and the maximum service life can reach 30 years. It is the most ideal valve for oil and natural gas pipelines.
Because the ball valve has the above advantages, it has a wide range of applications. The ball valve can be applied to: the nominal passage is from 8mm to 1200mm.
The nominal pressure ranges from vacuum to 42MPa and the working temperature ranges from -204°C to 815°C.