Solenoid valve knowledge introduction

Installation precautions are as follows:

1. When installing, please pay attention to the arrow on the valve body should be consistent with the flow direction of the medium. Do not install in places where there is direct dripping or splashing. The solenoid valve should be installed vertically upwards.

2. The solenoid valve should ensure normal operation within the fluctuation range of 15%-10% of the rated voltage of the power supply.

3. After the solenoid valve is installed, there must be no reverse pressure difference in the pipeline. It needs to be powered on several times to make it suitable for use.

4. The solenoid valve should be thoroughly cleaned before installation. The medium to be passed should be free of impurities. Install the filter in front of the valve.

5. When the solenoid valve fails or is cleaned, a bypass device should be installed to ensure the system continues to operate.

Failure and elimination

First, the solenoid valve does not work after power-on check whether the power supply wiring is bad → re-wiring and connector connection check whether the power supply voltage is within the ± working range - → adjust the normal position range whether the coil is off welding → re-welding the coil short-circuit → replace the coil working pressure Whether the difference is not suitable → adjust the differential pressure → or replace the proportional solenoid valve fluid temperature is too high → replace the proportional solenoid valve with impurities to make the main valve core and moving iron core of the solenoid valve jam → clean, if there is seal damage should be replaced Sealing and installing the filter liquid is too viscous, the frequency is too high and the life is up to → replace the product

Second, the solenoid valve can not close the main valve core or the iron core seal has been damaged → replace the seal fluid temperature, viscosity is too high → replace the solenoid valve of the opposite port has impurities into the solenoid valve spool or moving iron core → cleaning The life of the spring has reached or deformed → the orifice of the orifice is replaced. The cleaning frequency is too high or the life is up. → Re-select the product or update the product.

Third, other conditions Internal leakage → Check the seal is damaged, the spring is not properly assembled. External leakage → loose connection or seal is broken → tighten the screw or replace the seal. There is noise when energized → the solid parts on the head are loose and tightened. The voltage fluctuation is not within the allowable range and the voltage is adjusted. The iron core suction surface is dirty or uneven, and it is cleaned or replaced in time. Uses of Solenoid Valves Solenoid valves: Switching controls for liquid and gas lines are two DO controls. Generally used for the control of small pipes. Solenoid valve: It can only be used as a switch quantity. It is DO control and can only be used for small pipe control. It is common in DN50 and below pipes, and it is rare. 1. Switch form: The solenoid valve is driven by the coil and can only be turned on or off. The switching time is short.

2. Nature of work: Solenoid valves generally have a small flow coefficient and a small difference in working pressure. For example, a general 25-caliber solenoid valve has a smaller flow coefficient than a 15-caliber electric ball valve. The solenoid valve is driven by an electromagnetic coil and is relatively easily damaged by voltage surges. Equivalent to the role of the switch, is the role of opening and closing. Solenoid valves can be reset by general power failure. For such functions, electric valves require a reset device.

3. Applicable process: Solenoid valve is suitable for some special process requirements, such as leakage, special fluid medium, etc., which is more expensive.

The difference between solenoid valve and electric valve

1. Switch form: The solenoid valve is driven by the coil and can only be turned on or off. The switching time is short. The drive of the electric valve is generally driven by a motor. It takes a certain amount of time to simulate the opening or closing action, and can be adjusted.

2. Nature of work: Solenoid valves generally have a small flow coefficient and a small difference in working pressure. For example, a general 25-caliber solenoid valve has a smaller flow coefficient than a 15-caliber electric ball valve. The solenoid valve is driven by an electromagnetic coil and is relatively easily damaged by voltage surges. Equivalent to the role of the switch, is the role of opening and closing. The drive of the electric valve is generally a motor, which is more resistant to voltage shock. The solenoid valve is fast open and fast closed. It is generally used in small flow and small pressure, and the electric switch is required in the place where the switching frequency is large. The opening of the electric valve can be controlled. The state has open, closed, half open and half closed, which can control the flow of the medium in the pipeline and the solenoid valve can not meet this requirement. Solenoid valves can be reset by general power failure. For such functions, electric valves require a reset device.

3. Applicable process: Solenoid valve is suitable for some special process requirements, such as leakage, special fluid medium, etc., which is more expensive.

The main features of the solenoid valve

(1) The external leakage is blocked, the internal leakage is easy to control, and the use is safe. Internal and external leakage is an essential element of safety. Other self-control valves typically extend the valve stem and control the rotation or movement of the spool by an electric, pneumatic, hydraulic actuator. This must solve the problem of external leakage of the long-acting valve stem dynamic seal; only the electromagnetic valve is applied by the electromagnetic force on the iron core sealed in the magnetic isolation valve of the electric control valve, there is no dynamic seal, so the external leakage is easy to block . The electric valve torque control is not easy, it is easy to produce internal leakage, and even the stem of the valve stem is broken; the structure of the electromagnetic valve is easy to control the internal leakage until it drops to zero. Therefore, solenoid valves are particularly safe to use, especially for corrosive, toxic or high temperature media.

(2) The system is simple, then the computer is connected, and the price is low. The solenoid valve itself is simple in structure and low in price, and is easy to install and maintain compared to other types of actuators such as regulating valves. What's more remarkable is that the self-control system is much simpler and the price is much lower. Since the solenoid valve is controlled by the switching signal, it is very convenient to connect with the industrial computer. In today's era of computer popularization and price drop, the advantages of solenoid valves are even more obvious.

(3) The action express, the power is small, and the shape is light. The solenoid valve response time can be as short as a few milliseconds, even a pilot solenoid valve can be controlled in tens of milliseconds. Due to the self-contained loop, it is more sensitive than other self-controlled valves. The well-designed solenoid valve coil has low power consumption and is an energy-saving product. It can also be used to trigger the action and automatically maintain the valve position, and it does not consume electricity at all. The solenoid valve has a small size, which saves space and is light and beautiful.

(4) The adjustment accuracy is limited, and the applicable medium is limited. Solenoid valves usually only have two states of switching. The valve core can only be in two extreme positions and cannot be continuously adjusted. (There are many new ideas for breaking through, but they are still in the trial and trial stage), so the adjustment accuracy is also limited. Solenoid valves have high requirements on the cleanliness of the medium. Granular media cannot be used. If it is an impurity, it must be filtered first. In addition, viscous media is not suitable, and the viscosity range of the medium for a particular product is relatively narrow. (5) Various models and wide range of uses. Although the solenoid valve is inherently insufficient, the advantages are still outstanding, so it is designed into a wide variety of products to meet a variety of different needs, and is extremely versatile. The advances in solenoid valve technology are also centered around how to overcome the inherent deficiencies and how to better develop their inherent advantages.