Solenoid valve as an instrument of automation, in recent years a sharp increase in the amount. This paper analyzes the main features of the solenoid valve, and focusing on the application of the angle of the development of the domestic mature technology to make a brief overview, respectively, in the streamlined, intelligent, universal, dedicated direction made a survey, and slightly affect the solenoid valve technology Development of social factors for some discussion. Key words: Solenoid valve, intelligent, streamlined, generalized, dedicated multi-function, self-maintaining, combination valve, three valves, explosion-proof valve First, the main features of the solenoid valve (1) Control, the use of safety. Internal and external leaks are elements that endanger safety. Other self-control valve stem usually stick out by the electric, pneumatic, hydraulic actuator control spool rotation or movement. This must solve the long-term action of the valve stem seal leakage problems; only the electromagnetic valve is the role of electromagnetic force sealed in the magnetic separation within the sleeve to complete the core, there is no dynamic seal, so easy to block leakage. Electric valve torque control is not easy, prone to internal leakage, and even pulled off the stem head; structure of the solenoid valve easy to control the internal leakage until it drops to zero. Therefore, the use of special safety solenoid valve, especially for corrosive, toxic or high temperature medium. (2) The system is simple, then the computer, low prices Qian. Solenoid valve itself is simple, the price is low, compared to other types of actuators such as regulating valve easy to install and maintain. Even more remarkable is the composition of the control system is much simpler, the price is much lower. As the solenoid valve is the switch signal control, and industrial computer connection is very convenient. In today's popularization of computers, the price plummeted era, the advantages of the solenoid valve even more pronounced. (3) action express delivery, power is small, lightweight appearance. Solenoid valve response time can be as short as a few milliseconds, even the pilot solenoid valve can be controlled within a few tens of milliseconds. Since the self loop, more responsive than other self-controlled valves. Well-designed solenoid valve coil power consumption is very low, is an energy-saving products; can also be done only trigger action, automatically maintain the valve position, usually do not consume electricity. Solenoid valve small size, saving space, but also lightweight and beautiful. (4) regulation accuracy is limited, the applicable medium is limited. Solenoid valve usually only switch two states, the spool can only be in two extreme positions, can not be adjusted continuously (trying to break a lot of new ideas, but are still in the trial stage of the trial) so the regulation accuracy is subject to certain restrictions. Solenoid valve on the media have a higher cleanliness requirements, including granular media can not be applied, in the case of impurities must be filtered out. In addition, viscous media do not apply and the range of medium viscosities for a particular product is relatively narrow. (5) Model variety, wide range of uses. Although solenoid valve inherent deficiencies, the advantages are still very prominent, so it is designed into a wide range of products to meet a variety of different needs, the use of a very wide range. Solenoid valve technology is also progress around how to overcome the inherent deficiencies, how to better play its inherent advantages and expand. Second, the introduction of the development of solenoid valve technology 2.1 streamline the development of the direction of the best to be Jane, only a simple ability to spread for a long time. This is also the permanent pursuit of scientists and engineers. (1) Simplify the control loop o The past, a large number of actuators using pneumatic and electric control loop, which increases the complexity of the system, while the pilot-type solenoid valve is formed within the valve using the working medium itself control loop, the structure is very simple . Solenoid valve in the past a number of technical parameters are still limited, and now the domestic solenoid valve diameter has been extended to 30Omm; medium temperature as low as - 200 ℃, up to 450 ℃; working pressure from the vacuum to 25MPa. Action time from a few seconds to a few milliseconds. The new development of these technologies can completely replace the existing bulky and expensive two-position controlled quick shut-off valves, pneumatic on-off valves and electric on-off valves, and can partially replace continuously-regulated pneumatic and electric control valves. (How to better meet the regulatory requirements of precision, but also below). Foreign textile, light industry, urban construction and other industries have switched to a large number of solenoid valves, while the metallurgical and chemical industries take the lead in the auxiliary system to use more and more solenoid valves. Domestic self-control professional and technical personnel have been more and more attention to the solenoid valve. (2) to simplify the piping system. Automatic control valve work in the pipeline must be equipped with some auxiliary valves and pipe fittings. For example, the isolated bypass shown in Figure 1 is a typical installation. There are three manual valves, manual valve 1 is bypass valve, manual standby. While manual valves 2 and 3 are isolation valves to ensure the on-line maintenance of the automatic control valve 5. Of course, you have to have two tees 4 and union 6. This pipeline system occupies a large space, installation and time-consuming, but also easy to leak. ZDF series of multi-function solenoid valve cleverly eliminates the need for these additional accessories is still isolated bypass function, which won the Geneva International Gold Award for new technologies. Automatic control valve in front of the need to install filters. It is also often necessary to install check valves to prevent interference between pipes when using multiple self-contained valves. Now, one-way solenoid valves, combination solenoid valves and filtered solenoid valves have all played their part in simplifying piping. (The company also introduced the recoil filter valve, and the switch and filter function, and without having to remove the valve can flush the filter, won the Sino-US invention patent.) (3) to simplify the wide door structure and technology. Solenoid valve is the principle and structure are simple automatic control valve, but also to further simplify. Household appliances washing machines, refrigerators equipped with solenoid valve, the structure of parts and processes are suitable for mass production. Ordinary solenoid valve coil components have been used plastic package to reduce the failure of lead wire failure, easy to achieve waterproof, explosion-proof and other protection requirements. Valve body, bonnet and other components have been used precision casting, forging and other technology, engineering plastic solenoid valve has also been listed in bulk. Domestic explosion-proof solenoid valve is not just Flameproof, as well as encapsulated type, intrinsically safe type. High-pressure and high-temperature solenoid valve also appeared to simplify the structure and technology. 2.2 The development of intelligent direction This mainly refers to the solenoid valve and smart meters with better coordination to improve system control accuracy and reliability. It is generally considered difficult to achieve very high bit-position adjustment accuracy, however, in many occasions the proper way to achieve the required high accuracy, and significant cost savings. (1) double combination of electromagnetic wide. This is a combination of solenoid valves of different sizes. A large number of tanker oil metering accuracy of up to 0.02%, are used double solenoid valve. Open the large valve, making refueling in a relatively short period of time near completion; then the valve closed, supplemented by a small valve to ensure flow accuracy. This technology has been applied abroad for many years, the products by the world-renowned professional solenoid valve manufacturer ASCO Honeywell and other companies. Now the company produces double solenoid valve has reached the target of imported products, as well as unique performance. By the way, it is pointed out that the measurement of the large flow in domestic oil depots is still introducing or imitating foreign complicated multi-stage shut-off valves with less stable performance. Such products are not manufactured by world-renowned professional companies because the market demand is not enough to attract them interest. In fact, our oil depot with a large domestic production of dual-valve portfolio, the effect will be much better. Double combined valve is also commonly used to control temperature, pressure, liquid level and other parameters. Large valve to ensure the basic amount of valve to provide compensation. In relatively stable parameters of the system, this bit-type control can be quite high precision. For systems with large parameter variations, the rate of change is still subject to certain constraints, such as temperature control systems, which are still affected by thermal inertia. Therefore, the proper use of double combined valve to meet the control requirements of the premise relative to the control valve can significantly reduce costs. (3) Three-position solenoid valve and three-position solenoid valve The three-position solenoid valve has three working positions. Normally, it is not energized and is in the state of micro-opening. The valve provides initial flow. To an electrical signal, the solenoid valve is fully open, ; To another electrical signal, valve off valve. The valve also comes with a manual device, making long-term off the valve without electricity. Three solenoid valve can be seen as a more compact structure of the double solenoid valve, it is easy to achieve three-bit regulation, has been a lot of applications. A further thought is that n sizes of solenoid valves make up 2n kinds of flow, analogous to digital circuits that this combination valve is a digital valve. In fact, two different sizes of two or three valves can produce 24 = 16 or 32 = 9 kinds of flow, has been able to achieve very high accuracy. In principle, it has advantages with industrial computer, but due to the large number of applications that have not been put forward, this technology is still in the experimental stage. (3) Since the maintenance of electromagnetic solenoid valve self-holding solenoid valve is just an instantaneous switch to complete the valve action, the spool position without electricity to maintain. It has the advantage of saving energy, especially when using batteries as power supply, and can not consider the temperature rise, so the coil has a long service life and high safety at high and low temperature and explosion proof. Common mechanical holding and permanent magnet to maintain, and is divided into double coil and single coil, with a single magnetic coil to keep the structure is the most simple. It is to change the polarity of the DC power supply corresponding to the valve switch to change the two states. This solenoid valve installed separately coil external wiring need to add the switch, and with the smart meter is very convenient. IC card pre-paid gas meter and the meter is equipped with a solenoid valve is one of the keys to the success of the instrument, which self-sustaining technology is an important factor in the success or failure of the solenoid valve, the domestic self-sustaining electromagnetic has matured, the company has more Smart watch factory to provide support. 2.3 The development of universal direction Solenoid valve is widely used, but the use of the situation is vastly different, enhance the common performance of reducing manufacturing, purchasing and sales, storage, installation and maintenance costs, in recent years this has taken a big step. (1) Adjustable response time to give the electrical signal to the valve core action completed time is called the response time. Different occasions, I hope the switch speed is different, there are four combinations: Quick-open fast-closing ---- for quick reaction system; Quick slow-closing ---- for the prevention of water hammer; Quake off; slow to slow one by one for a smooth transition. ZDF multi-function solenoid valve can adjust to any state, the application is very flexible. (2) expansion of the medium applicable standard solid. Solenoid valve and other self-control valve is different in medium viscosity range is narrow, so the air, water, steam, oil and other media for the pilot solenoid valve its structural parameters are different; generally can not be universal. The ZDF multi-function solenoid valve with only a small screw, but it has gas, water, oil, universal, but also greatly expand the scope of oil viscosity, popular. (3) adjustable opening and moving and kiln solenoid valve often use it also want to have both manual functions, as a power outage or failure backup.
Power Plant,Power Industries,Power Generation,Diesel Power Plant
Jinan Boiler Group Co., Ltd. , https://www.jinanboilergroup.com