Selection Guide Of Solenoid Valve

Selection Guide Of Solenoid Valve:

1. Selection of solenoid valve according to pipeline parameters: size specification (DN) , interface mode

1.1 Determine the diameter (DN) size according to the on-site pipe internal diameter size or flow rate requirement.

1.2 interface mode, generally greater than DN50 to choose the flange interface, less than or equal to DN50 according to user needs free choice.

2. According to the fluid parameter choice solenoid valve: Material, temperature group

2.1 Corrosive fluid: Appropriate Selection of corrosion-resistant solenoid valve and all stainless steel; edible ultra-clean fluid: Appropriate selection of food-grade stainless steel material solenoid valve.

2.2 High-temperature Fluid: to choose the use of high-temperature electrical materials and sealing materials manufacturing solenoid valve, and to choose the type of piston structure.

2.3 Fluid State: Large to gaseous, liquid or mixed state, especially if the caliber is larger than DN25.

2.4 Fluid viscosity: Usually in the 50cSt can be optional below, if more than this value, choose high viscosity solenoid valve.

3. Selection of solenoid valve according to pressure parameters: principle and structure of varieties

3.1 Nominal pressure: This parameter has the same meaning as other general-purpose valves and is based on the nominal pressure of the pipeline.

3.2 Working pressure: if working pressure is low, the principle of direct-acting or step by step direct-acting must be chosen; the direct-acting, step by step direct acting and pilot acting can be chosen when the minimum working pressure difference is over 0.04 MPA.

4. Voltage Selection: Conventional Voltage, such as AC220V, DC24V, DC12V, should be preferred for voltage specifications.

5. Depending on the duration of the work: Normally closed, normally open, or continuously energized.

5.1 If the opening time is short or the opening and closing time is not long, then choose normally closed type.

5.2 But some for the safety protection of the working conditions, such as the furnace, kiln flame monitoring, it can not choose open, should choose long-term electrification.

6. Selection of auxiliary functions according to Environmental Requirements: explosion-proof, check-back, manual, waterproof fog, drenching, diving.

6.1 Explosive Environment: The electromagnetic valve of the corresponding explosion-proof grade must be selected.

6.2 Submersible solenoid valves (IP68 and above) shall be used for fountains.

Electromagnetic Valve selection needs to pay attention to the following 4 characteristics:

1. Security:

(1) Corrosive media: Plastic Wang solenoid valve and all stainless steel should be selected; for strong corrosive media must choose isolation diaphragm type. Case of CD-F. Z3CF. Neutral medium, also should choose copper alloy for the valve Shell Material solenoid valve, otherwise, the valve shell often rust chip off, especially action is not the frequent occasion. The ammonia valve can not use copper.

(2) Explosive environment: must choose the corresponding explosion-proof grade product, open-air installation or dust should choose waterproof, dust-proof varieties.

(3) The nominal pressure of the solenoid valve should exceed the maximum working pressure in the pipe.

2. Applicability:

(1). Dielectric characteristic

1.1 Different kinds of solenoid valves are used in gas, liquid or mixed state.

1.2 Medium temperature products of different specifications, otherwise the coil will burn off, seals aging, seriously affect the life.

1.3 Medium viscosity, usually below 50cSt. If more than this value, diameter greater than 15mm with multi-functional solenoid valve for special orders. Diameter less than 15mm high viscosity solenoid valve.

1.4 Medium cleanliness is not high should be installed in front of the solenoid valve recoil filter valve, low pressure can choose direct-acting diaphragm solenoid valve.

1.5 medium temperature should be selected in the electromagnetic valve to allow the scope.

(2). Pipe Parameter

2.1 select valve opening and type according to medium flow direction and pipe connection.

2.2 Nominal diameter is selected according to flow rate and valve KV value, also can choose same pipe inner diameter. Please note that some manufacturers are not marked Kv value, often valve hole size is less than the diameter of the interface, must not covet low prices and mistakes.

2.3 Working pressure drop: The indirect pilot type can be selected if the minimum working pressure difference is above 0.04 MPA, and the direct type or step-by-step direct type must be selected if the minimum working pressure difference is close to or less than zero.

(3). Environmental conditions

3.1 the maximum and minimum temperatures of the environment shall be selected within the allowable range and special orders shall be made if there are any overruns.

3.2 in the environment relative humidity is high and has the dripping rain and so on occasion, should choose the waterproof solenoid valve

3.3 special types, such as marine solenoid valves, should be selected for vibration, bump and impact.

3.4 Corrosion Resistance in corrosive or explosive environments shall be selected according to safety requirements

3.5 If the environment space is limited, please select the multi-function solenoid valve for online maintenance.

(4). Power Condition

4.1 According to the type of power supply, AC and DC solenoid valves are selected. In general, AC power is easy to access.

4.2 The tolerance of voltage is ±10%. If over-tolerance, to take voltage-stabilizing measures or special order requirements.

4.3 The rated current and consumed power shall be selected according to the power supply capacity. Must pay attention to AC starting when the VA value is high, in the capacity is insufficient should give priority to the use of indirect solenoid valve.

4.4 Control accuracy: General solenoid valve only open, closed two positions, in the control of high precision requirements and parameter requirements of smooth, please choose multi-position solenoid valve.

4.5  Leakage: The leakage value given in the sample is of the commonly used economic grade. If it is too high, please place special order.

3. Reliability:

(1) working life, this item does not include the ex-factory test item, belongs to the type test item. In order to ensure the quality, we should choose the reliable products of regular manufacturers.

(2) working system: divided into long-term working system, repeated short-term working system and short-term working system. The company’s conventional products are long-term work system, that is, the coil allows long-term electrification work. For a long time to open the valve only a short time to close the case, it is appropriate to choose the normally open solenoid valve. It can be used in short-time working system and large batch, special order can be made to reduce power consumption.

(3) working frequency: When the action frequency is high, the structure should preferably choose the direct-acting electromagnetic valve and the power supply should preferably listen to the AC.

(4) action reliability: Strictly speaking, this test has not been formally included in the professional standard of solenoid valve in our country. Some occasions action number is not much, but the reliability requirements are very high, such as fire, emergency protection, must not be taken lightly. Especially important, should also take two to use double insurance.

4. Economy:

It selects one of the scales, but must be in the safe, suitable, the reliable foundation, the economy.

Economy is not only the price of the product, but also give priority to its function and quality as well as the cost of installation, maintenance and other accessories.

More importantly, a solenoid valve in the whole automatic control system in the whole automatic control system and even in the production line of the cost is negligible, if greedy small cheap and the wrong early damage group is huge.