Development direction of solenoid valve

1、 The development of the direction of refinement and simplification is from essence to simplicity. Only simple ones can spread for a long time, which is also the permanent pursuit of scientists and engineers.

(1) In the past, pneumatic and electric control circuits were widely used in the actuators to simplify the control circuit, which increased the complexity of the system, while the pilot type solenoid valve formed a control circuit in the valve using its own working medium, with a very simple structure. In the past, many technical parameters of the solenoid valve at home and abroad were still limited, and the diameter of the solenoid valve at home had been expanded to 30 OMM; the medium temperature was as low as - 200 ℃, as high as 450 ℃; the working pressure was from vacuum to 25 MPa. The action time is from ten seconds to several milliseconds. The new development of these technologies can completely replace the original huge and expensive two position controlled quick cut-off valve, pneumatic on-off valve and electric on-off valve, and can also partially replace the continuously regulated pneumatic and electric control valve. In foreign countries, many industries such as textile, light industry and urban construction have used solenoid valves, while metallurgy and chemical industry have taken the lead in using more and more solenoid valves in auxiliary system. More and more attention has been paid to the solenoid valve by the domestic automatic control professionals.

(2) In order to simplify the operation of automatic control valve in pipeline system, some auxiliary valves and pipe fittings should be used. There must be three manual valves, of which the manual valve 1 is a bypass valve, which is manually standby. Manual valves 2 and 3 are isolation valves to ensure online maintenance of automatic control valve 5. Two tees 4 and union 6 are also required. This kind of pipeline system takes up a large space, which is time-consuming to install and easy to leak. The ZDF series multi-functional solenoid valve has ingeniously omitted these additional accessories and still has the function of isolating bypass, so it won the gold medal of Geneva International new technology. The front of the automatic control valve needs to be equipped with a filter. When multiple automatic control valves are used together, one-way valves are often installed to prevent interference between pipes. One way solenoid valve, combined solenoid valve and solenoid valve with filter have all played a role in simplifying pipeline.

(3) The simplified wide gate structure and process solenoid valve belong to the automatic control valve with simple principle and structure, but they need to be further simplified. The structure and technology of the components of the solenoid valve for washing machine and refrigerator in home appliance industry are suitable for mass production. The coil components of common solenoid valve have been packed in plastic to reduce the breakages of outgoing line, and to meet the protection requirements of waterproof and explosion-proof. Valve body, valve cover and other parts have been used in precision casting, forging and other processes, and engineering plastic solenoid valves have also been listed in batches. Domestic explosion-proof solenoid valve is not only flameproof type, but also pouring type and intrinsic safety type. High pressure and high temperature solenoid valve also appeared to simplify the structure and process.

2、 The development of intelligent direction mainly refers to how the solenoid valve and intelligent instrument better cooperate to improve the control accuracy and reliability of the system. Generally speaking, it is difficult to achieve very high accuracy of position adjustment. However, in many cases, it can achieve the required high accuracy by using appropriate methods, which greatly saves the cost.

(1) Double combination electromagnetic width. This is a combination of solenoid valves of different sizes. A large number of fuel dispensers use double solenoid valves to measure oil with a precision of 0.02%. The large valve is opened to make the refueling almost complete in a short time; then the large valve is closed and the small valve is added to ensure the flow accuracy. This technology has been used for many years in foreign countries, and the products are manufactured by the world famous solenoid valve professional company ascohoneywell and other companies. By the way, it is pointed out that large flow metering of domestic oil depots is still introducing or imitating foreign multi-stage shut-off valves with complex structure and unstable performance. This product is not made by world-famous professional companies, because the market demand is not enough to attract their interest. In fact, the oil depot adopts the domestic double combination valve with large flow, and the effect will be much better. Double combination valve is often used to control temperature, pressure, liquid level and other parameters. The large valve guarantees the basic quantity, while the small valve provides the compensation quantity. In the system with relatively stable parameters, this kind of position control can achieve quite high precision. For some systems with large parameter changes, the rate of change is still restricted, for example, the temperature control system is still affected by the heating inertia. Therefore, the use of a proper dual combination valve can greatly reduce the cost compared with the control valve on the premise of meeting the control requirements.

(2) The three position solenoid valve and the three position solenoid valve of the digital valve have three working positions. They are not electrified at ordinary times and are in the micro opening state, so the valve provides the initial flow; one kind of electrical signal is given, the solenoid valve is fully open, providing the large flow; another kind of electrical signal is given, the valve is closed. The valve is also equipped with a manual device, so that the power consumption is not required when the valve is closed for a long time. Three position solenoid valve can be regarded as a more compact double solenoid valve. It is very convenient to realize three position adjustment and has been widely used. The further idea is that n solenoid valves with a certain proportion of size constitute 2n kinds of flow, which is similar to the digital circuit called the combination valve as a digital valve. In principle, it has advantages in matching with industrial control computer, but it is still in the experimental stage due to the lack of a large number of requirements in the application field.

(3) Self holding electromagnetic wide self holding solenoid valve is to complete the valve opening and closing action only by momentary power on, and the position of valve core does not need power to maintain. Its advantages lie in energy saving, especially in the case of battery power supply, and temperature rise is not considered, so the coil has a long life and high safety in high and low temperature, explosion-proof and other occasions. The common ones are mechanical holding and permanent magnet holding, which are divided into two coils and single coil. The single coil magnetic holding structure is the simplest. It is to change the polarity of the DC power supply to change the two states of the corresponding valve switch. This kind of solenoid valve needs a change-over switch to install the external wiring of the coil separately, and it is very convenient to match with the intelligent instrument. The solenoid valve of IC card pre charge gas meter and water meter is one of the key to the success of the instrument, and the self-sustaining technology is an important factor of the success of the solenoid valve. The domestic self-sustaining solenoid has become increasingly mature.

3、 The development of the general direction of solenoid valve application is very wide, but the use situation is very different, enhance the general performance and reduce the cost of manufacturing, purchasing, storage, installation and maintenance.

(1) The response time can be adjusted to give the time from the electrical signal to the completion of the spool action is called the response time. There are four combinations: fast on and fast off - for fast response system; fast on and slow off - to prevent water hammer; slow on and fast off - for slow on and quick off; slow on and slow off - for smooth transition. ZDF multi-function solenoid valve can be adjusted in any state, and its application is very flexible.

(2) Expansion media is suitable for consolidation. The difference between solenoid valve and other automatic control valves lies in the narrow application range of medium viscosity, so the structure parameters of air, water, steam, oil and other media for pilot solenoid valve are different; generally speaking, they are not universal. The ZDF multi-function solenoid valve only uses a small screw, but it can be used in gas, water and oil. Moreover, the viscosity of the oil is widely used, which is very popular.

(3) When the opening is adjustable and the kiln solenoid valve is in use, it is often expected to have both manual functions, as standby in case of power failure or failure. Generally, the manual device can only open or close the valve manually, which is called fully manual. The manual device can also preset the opening of the valve. Generally, the manual device can only preset the maximum or minimum opening of the valve, while the full manual device can preset the maximum or minimum opening respectively. ZDF multi-function solenoid valve belongs to complete manual type. Other models of solenoid valve can be equipped with simple general manual device as required.