Safety:
1, corrosive media: the king should use Plastic Solenoid Valve and all stainless steel; for highly corrosive media must use isolation diaphragm. Neutral medium, it should use copper alloy shell material for the Solenoid Valve, otherwise the valve shell desquamation often rust, especially the action does not frequent occasions. Ammonia can not be used with the valve copper.
2, explosive atmospheres: You must choose the appropriate proof grade products, open-air installation or dust should be used more occasions, waterproof, dust-proof varieties.
3, the solenoid valve nominal pressure should exceed the maximum working pressure tube.
Applicability:
1, the dielectric properties
1) The quality of gas, liquid or mixed states were selected to different varieties of solenoid valves;
2) Medium temperature products of different specifications, otherwise the coil will burn, seals aging, seriously affect the life of life;
3) medium viscosity, usually 50cSt the following. If it exceeds this value, when the diameter is larger than 15mm, with multi-function solenoid valve; when the diameter is less than 15mm, high viscosity solenoid valve.
4) medium cleanliness is not high when the solenoid valve should be fitted before the recoil filter valve, the pressure is low, it can be used straight diaphragm solenoid valve;
5) If the directional flow of the medium, and not allowed back, needed two-way flow;
6) The medium temperature should be chosen within the allowable range solenoid valve.
2, pipe parameters
1) Select the valve openings and model according to media flow requirements and pipe connection;
2) According to the flow and valve Kv values for the selected nominal diameter, with pipe diameter also optional;
3) Working pressure: minimum working pressure is more than can be used in 0.04Mpa indirect Pilot; minimum working pressure close to or less than zero must be selected direct-acting or step direct.
3, the environmental conditions
1) the highest and lowest temperature of the environment should be selected in the allowable range;
2) environment with high relative humidity and a drop of rain and so on, should be selected Water Solenoid Valve;
3) environment, often vibration, bumps and shocks should choose special varieties of occasions, such as marine solenoid valve;
4) in a corrosive or explosive environments use should be preferred in accordance with security requirements resistance to hair loss type;
5) If the restricted environmental space, need to use multi-function valve, because eliminating the bypass and three manual valves and easy online service.
4, supply conditions
1) According to the power supply types were selected to AC and DC solenoid valves. Generally convenient access to AC power;
2) Voltage specification with the best preferred AC220V.DC24V;
3) AC power supply voltage fluctuations are usually chosen +% 10% .- 15%, DC to allow ±% 10 or so, should the ultra-poor, regulators should take measures;
4) should be selected according to the rated current and power consumption power capacity. VA should be noted that the exchange of high value when starting, inadequate capacity should be preferred in the indirect electromagnetic valve guide.
5. Control Accuracy
1) General electromagnetic valve only opening and closing two locations, in the control of high precision and parameters need to choose a number of solenoid valve for a smooth;
2) Action Time: refers to connect or disconnect signal to the main valve action completion time;
3) Leakage: leakage on the sample values are given for common economic level.
Reliability:
1, working life, this is not included in the factory pilot project, are type of pilot projects. To ensure the quality brand-name manufacturers should be regular elections.
2, the working standard: min long-term work, repeated short-time work and short-time working three. For a long time the valve opening of the case is only a short time off, are advised to use a normally open solenoid valve.
3, the working frequency: frequency of demanding action, the structure should be optimized direct acting solenoid valves, power to listen to the exchange preferred.
4, operating reliability
Strictly speaking, this test has not been formally included in China solenoid valve professional standards, to ensure the quality brand-name manufacturers should be regular elections. Not much movement on some occasions, but very high reliability requirements, such as fire, emergency protection, must not be taken lightly. Of particular importance, it should be taken once every two double insurance.
Economy:
One measure of its choice, but it must be in a safe, suitable, economical and reliable basis.
Economy is not only the price of the product, but also to give priority to their function and quality as well as installation and maintenance, and other accessories required for the costs.
More importantly, a solenoid valve in the automatic control system in the whole production line automatic control system as well as the share of the cost is minimal, if cheap wrong choice and damage the group is enormous.
