Types of Stainless Steel Three-Piece Ball Valves

    Stainless steel three-piece ball valves can be classified into various types based on different criteria such as structural form, connection mode, and drive mode. The following is a detailed introduction:

Classification by Structural Form

• Floating Ball Valve: In this type of valve, the ball is floating. Under the influence of the medium pressure, the ball can shift to some extent and press firmly against the sealing surface at the outlet end to ensure the outlet end is sealed. It features a simple structure and good sealing performance. However, all the load of the working medium borne by the ball is transferred to the outlet sealing ring. Hence, it's necessary to consider whether the sealing ring material can withstand the working load from the ball and the medium. This structure is commonly used in medium and low-pressure ball valves.
• Fixed Ball Valve: The ball of the fixed ball valve is fixed and doesn't move under pressure. Fixed ball valves usually come with floating valve seats. When pressed by the medium, the valve seats move to make the sealing ring press tightly against the ball to ensure sealing. Generally, bearings are installed on the upper and lower shafts of the ball, resulting in a small operating torque. This makes it suitable for high-pressure and large-diameter valves.
• Elastic Ball Valve: The ball of the elastic ball valve is elastic. Both the ball and the valve seat sealing ring are made of metal materials, and the sealing specific pressure is quite high. Relying solely on the pressure of the medium itself can't meet the sealing requirements, so external force must be applied. This type of valve is suitable for high-temperature and high-pressure media. The elastic ball obtains its elasticity by having an elastic groove opened at the lower end of its inner wall.

Classification by Connection Mode

• Threaded Connection Ball Valve: As the name suggests, this kind of valve connects to the pipeline through threads. It is characterized by convenient installation and disassembly and is suitable for small-diameter pipelines and situations where the connection doesn't need to be frequently disassembled.
• Flange Connection Ball Valve: The flange connection ball valve connects the valve body to the pipeline via flanges. This connection method offers high strength and good sealing performance and can withstand higher pressure and larger pipeline diameters. It is widely used in various industrial pipelines.
• Welded Connection Ball Valve: Welded connection ball valves are divided into butt-welded and socket-welded types. The butt-welded type is suitable for pipelines with higher pressure and larger diameters, as it has high connection strength. The socket-welded type is usually used for small-diameter pipelines, and its welding operation is relatively simple. This type of valve is appropriate for applications that demand a reliable connection and high sealing performance, such as in some high-pressure and high-temperature pipelines in the chemical industry.
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Classification by Drive Mode

• Manual Ball Valve: The manual ball valve is operated by a person turning the handle. It has a simple structure, is easy to operate, and is suitable for occasions where the frequency of opening and closing is not high and the flow rate doesn't need to be frequently adjusted. It is widely used in small-scale industrial production and civil water supply and drainage systems.
• Pneumatic Ball Valve: The pneumatic ball valve is driven by compressed air. It has the characteristics of fast opening and closing speed, a large driving force, and can be remotely controlled. It is suitable for situations that require frequent opening and closing and remote operation, such as in some automated production lines in the chemical industry and food industry.
• Electric Ball Valve: The electric ball valve is driven by an electric motor. It has high control accuracy, can achieve precise flow control and remote operation, and is suitable for occasions with high automation requirements, such as in some large-scale industrial control systems and intelligent building water supply and drainage systems.

In addition, stainless steel three-piece ball valves can also be classified according to other aspects, like port type (full port, reduced port). Different types of stainless steel three-piece ball valves possess their own features and application scenarios, enabling users to select the appropriate valve type based on specific working conditions and requirements.