Solenoid Valve Selection Guide

Feb 18,2019

Solenoid valve is a kind of industrial equipment controlled by electromagnetism which is a basic automatic components used to control the fluid and adjust the direction, flow rate, velocity and other parameters of medium in industrial control system. There are many kinds of solenoid valve, which play different roles at different locations in the control system. The most commonly used is one-way Valve, Safety Valve, Direction Control Valve, speed control valve, etc. Solenoid valve has excellent leak-proof performance, open and close quickly, low power, suitable for some corrosion, toxicity and other chemicals in the pipeline as cut-off use.

How to Select the Most Appropriate Solenoid Valve?
The selection of solenoid valve should follow the five principles of safety, scientific, reliability, applicability and economy, as well as the field working conditions such as: Valve size, working pressure, medium type, medium temperature, ambient temperature, power supply voltage, connection mode, installation mode, valve body material, special options, etc. 

1. Select the port size(DN) and connection type of solenoid valve according to pipeline parameters.
● Determine the port size(DN) according to the internal diameter of the on-site pipe or flow rate requirement.
● Connection type, generally if the port size is over DN50, customer should choose the flange connection, if ≤ DN50 could choose the connection according to their requirements.

2. Select the body material and temperature range of the solenoid valve according to fluid parameters.
● corrosive fluid: Appropriate selection of the corrosion-resistant solenoid valve or full stainless steel; 
● food grade fluid: Appropriate selection of sanitary stainless steel material solenoid valve.
● high-temperature Fluid: Appropriate selection of solenoid valve with high-temperature electrical materials and sealing material, choose the type of Piston structure.
● Fluid state: gas, liquid or mixed state, especially when the port size is larger than DN25 it has to be clarified when ordering.
● fluid viscosity: Usually if less than 50cst, it won’t influence the valve selection, if more than this value, choose high viscosity solenoid valve.

3. Select the principle and structure of the solenoid valve according to pressure parameters.
● Nominal pressure: This parameter is based on the nominal pressure of the pipeline.
● Working pressure: if working pressure is low(normally no more than 10bar), the direct lifting structure could be chosen; if working pressure is high(normally more than 10bar), the pilot operated structure could be chosen.

4. Select the Voltage
It is preferred to choose AC220V or DC24V as more convenient. 

5. Select the NC, NO, or Continuously electrified solenoid valve according to continuous working time.
● Select the Normally open type if the solenoid should be opened for a long time and the continuously opened time is longer than closed time.
● If the opening time is short and frequency is low, select the normally closed.
● But for some working conditions used for safety protection, such as furnace, kiln flame monitoring, cannot select normally open, it should select continuously electrified type.

6.Select the additional function such as Explosion proof and Water proof according to the site environment.
● Explosive Environment: must choose the corresponding explosion-proof class solenoid valve (our company existing: Exd IIB T4) .
● For fountains: must choose the underwater solenoid valve (IP68).