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Key points for selecting electric valves

2022年01月13日

1. Clearly define the use of electric valves in equipment or devices

Determine the working conditions of electric valves: the properties of the applicable medium, working pressure, working temperature, and operating control methods.


2. Choose the correct type of electric valve

The correct selection of valve type is based on the designer's full understanding of the entire production process and operating conditions. When selecting the type of electric valve, designers should first understand the structural characteristics and performance of each valve.


3. Determine the end connection of the electric valve

In threaded connections, flange connections, and welded end connections, the first two are the most commonly used. Threaded valves are mainly valves with a nominal diameter of less than 50mm. If the diameter is too large, it will be difficult to install and seal the connection. Flanged valves are easier to install and disassemble, but they are heavier and more expensive than threaded valves, making them suitable for pipeline connections of various diameters and pressures. Welded connections are suitable for heavy-duty conditions and are more reliable than flange connections. However, valves connected by welding are difficult to disassemble and reinstall, so their use is limited to situations where they can usually work reliably for a long time, or where the operating conditions are heavy and the temperature is high.


4. Selection of materials for electric valves

When selecting materials for valve shells, internal parts, and sealing surfaces, in addition to considering the physical properties (temperature, pressure) and chemical properties (corrosiveness) of the working medium, the cleanliness of the medium (with or without solid particles) should also be taken into account. Additionally, please refer to the relevant regulations of the country and user departments. Correct and reasonable selection of valve materials can achieve the most economical service life and optimal performance. The selection order of valve body materials is: cast iron carbon steel stainless steel, and the selection order of sealing ring materials is: rubber copper alloy F4.