Safety of explosion-proof solenoid valve
1. Corrosive media: Plastic King solenoid valve and stainless steel should be selected; isolation diaphragm type should be used for corrosive media. Example CD-F. Z3CF. In neutral medium, the solenoid valve with copper alloy as shell material should also be selected. Otherwise, rust debris often falls off from the valve shell, especially when the action is not frequent. Ammonia valves cannot be made of copper.
2. Explosive environment: It is necessary to select explosion-proof products. Waterproof and dust-proof products should be selected for outdoor installation or dust-proof occasions.
3. The nominal pressure of solenoid valve should exceed the maximum working pressure in the pipe.
Applicability of explosion-proof solenoid valves
1. dielectric properties
1.1 the quality of gas solenoid valve, liquid or mixed states, which are used in different varieties, for example ZQDF for air, ZQDF - Y - 2 for liquid, ZQDF (or -3) for the steam, otherwise easily lead to malfunction. ZDF series multi-function solenoid valves can be connected to gas. Liquid. It is best to specify the state of the media when the time is set.
1.2 medium temperature products of different specifications, otherwise the coil will burn, seals aging, seriously affect the life of life.
1.3 medium viscosity, usually below 50CST. If the value exceeds this value, the diameter is greater than 15MM, and the ZDF series multi-function solenoid valve is used for special orders. The diameter is less than 15MM, high viscosity solenoid valve is set.
1.4 medium cleanliness is not high when the electromagnetic valve should be installed before the recoil filter valve, low pressure style can be used direct acting diaphragm solenoid valve for example CD - P.
1.5 if the directional flow of media, and not allowed back ZDF - N and ZQDF - N single two-way flow required, please make a special request.
1.6 medium temperature should be selected in the allowable range of solenoid valve.
2. pipe parameters
2.1 select the valve port and type according to the requirement of media flow and the way of pipe connection. For example, for a pipeline to two channel switching, small path selection CA5 and Z3F, medium or large size select ZDF - Z1/2. If you want to control the convergence of two pipes, please select ZDF Z2/1.
2.2 according to the flow and valve KV value, the nominal diameter can be selected, and the inner diameter of the pipe can also be selected. Please note that some manufacturers are not marked with the KV value, often less than the interface valve hole size diameter, must not seek the lowest and delays.
2.3 working pressure difference
The indirect pilot type can be selected when the minimum working pressure difference is above 0.04 MPA; the direct or step-by-step direct type must be selected when the minimum working pressure difference is close to or less than zero.
3. environmental conditions
3.1 The highest and lowest temperatures of the environment should be within the allowable range, and special orders should be made if there is an overshoot.
3.2 in case of high relative humidity and dripping rain, we should choose waterproof solenoid valve.
3.3 in the environment, special varieties, such as marine solenoid valves, should be selected for occasions such as vibration, bump and impact.
3.4 use in corrosive or explosive environments should be preferred according to safety requirements.
3.5 If the environment space is limited, please choose multi-functional solenoid valve, because it saves bypass and three manual valves and is convenient for online maintenance.
4. power conditions
4.1 according to the type of power supply, AC and DC solenoid valves are selected respectively. Generally speaking, AC power supply is easy to use.
4.2 voltage specification should try to give priority to AC220V.DC24V.
4.3 Voltage fluctuation of power supply usually adopts +% 10%. -15% AC and +% 10% DC. If it is out of tolerance, voltage stabilization measures or special order requirements should be taken.
4.4 the rated current and power consumption should be selected according to the power supply capacity. It should be noted that the VA value is higher when AC starts, and the indirect guided solenoid valve should be preferred when the capacity is insufficient.
5. control accuracy
5.1 Ordinary solenoid valves have only two positions of opening and closing. When the control accuracy and parameters are required to be stable, please choose multi-position solenoid valves; Z3CF three-position open solenoid valves have three flow rates: micro-opening, full-opening and closed.
The combined multifunctional solenoid valve has four kinds of flow: full open, wide open, small open and full open.
5.2 Operation time: refers to the time when the electrical signal is connected or cut off to the main valve. Only the multi-function solenoid valve of our company can adjust the opening and closing time separately, which can not only meet the control accuracy requirements, but also prevent water hammer damage.
5.3 leakage
The amount of leakage given on the sample is the commonly used economic grade. If it is too high, please make a special order.
Reliability of explosion-proof solenoid valve
1, working life, this item is not included in the factory trial project, it belongs to the type test project. In order to ensure the quality, we should choose the famous brand products of regular manufacturers.
2, work standard: divided into long term work system, repeated short time work system and short time work system three kinds. The company's regular products are long term work, and the coil allows long term electricity. For a long time valve opening only a short time closure, it is advisable to use normally open solenoid valve. Used in short time work and bulk.
In large cases, special orders can be made to reduce power consumption.
3. Working frequency: When the operating frequency is high, the structure should select the direct-acting solenoid valve and the power supply should listen to the alternating current.
4. Motion reliability
Strictly speaking, this test has not yet been formally included in the professional standards of solenoid valves in China. In order to ensure the quality, we should choose the famous brand products from the regular manufacturers. In some occasions, the number of actions is not much, but the reliability requirements are very high, such as fire protection, emergency protection, etc., must not be taken lightly. In particular, two double insurance should be adopted.
Economy of explosion-proof solenoid valve
It is one of the yardstick of choice, but it must be an economy based on safety, applicability and reliability.
Economy is not only the price of the product, but also the function and quality of the product, as well as the cost of installation, maintenance and other accessories.
More importantly, the cost of a solenoid valve in the whole automatic control system and even in the production line is negligible. If you want to be cheap and choose the wrong one early, the damage group will be huge.
