What is a electromagnetic valve
What is a electromagnetic valve?
Electromagnetic valve is an industrial equipment controlled by electromagnetism. It is an automatic basic component used to control fluid. It belongs to actuator, not limited to hydraulic and pneumatic. It is used to adjust the direction, flow, speed and other parameters of the medium in the industrial control system. The electromagnetic valve can cooperate with different circuits to achieve the desired control, and the control accuracy and flexibility can be guaranteed. There are many kinds of electromagnetic valves, different electromagnetic valves play a role in different positions of the control system, the most commonly used are one-way valve, safety valve, direction control valve, speed regulating valve, etc.
Working Principle of electromagnetic valve
The electromagnetic valve has a closed chamber with holes in different positions. Each hole is connected to a different oil tube. The middle of the chamber is piston, and the two sides are two electromagnet, which side of the magnet coil is attracted to which side, through the movement of the control valve body to open or close different oil discharge holes, and the oil inlet hole is normally open, hydraulic oil will enter different oil pipes, and then push the piston of the oil cylinder through the pressure of oil. The piston then drives the piston rod and the piston rod to drive the mechanical device. In this way, the mechanical movement is controlled by controlling the current on and off of the electromagnet.
The main category of electromagnetic valve
1. The electromagnetic valve is divided into three categories in principle:
Direct-acting electromagnetic valve
- When energized, the electromagnetic force generated by the electromagnetic coil lifts the closing piece from the valve seat and the valve opens;
- When powered off, the electromagnetic force disappears, the spring presses the closing piece on the valve seat and the valve closes.
Features: it can work normally in vacuum, negative pressure and zero pressure, but the diameter generally does not exceed 25mm.
Step-by-step direct-acting electromagnetic valve
Principle: it is a combination of straight-moving and pilot-operated. When there is no pressure difference between the inlet and the outlet, the electromagnetic force directly lifts the pilot small valve and the main valve shut parts upward in turn, valve open. When the start differential pressure of the inlet and the outlet reaches, after electrifying, the electromagnetic force leads to a small valve, the pressure in the inferior space of the main valve rises, and the pressure in the superior space drops, thus pushing the main valve upward by the use of differential pressure; When, the pilot valve uses spring force or medium pressure to push the closing piece and move downward to close the valve.
Features: It can also be operated under zero pressure difference or vacuum and high pressure, but the power is large and it is required to be installed horizontally.
Pilot-operated electromagnetic valve
Principle: when power is switched on, electromagnetic force will open the pilot hole, and the pressure of the upper chamber will drop rapidly, forming an upper lower and higher pressure difference around the closed parts, and the fluid pressure will push the closed parts to move the valve upward to open; when the power is cut off, the spring force closes the pilot hole, and the inlet pressure quickly forms a lower, higher and higher pressure difference around the closing valve through the bypass hole, and the fluid pressure pushes the closing piece to move downward to close the valve.
Features: The upper limit of fluid pressure range is high and can be installed arbitrarily (customized) but must meet the condition of fluid pressure difference.
2. The electromagnetic valve can be divided into six sub-categories according to the difference in valve structure and material and principle: direct acting Diaphragm structure, step-by-step direct acting Diaphragm structure, pilot Diaphragm structure, direct acting piston structure, step-by-step straight-acting piston structure and pilot piston structure.
3. Solenoid valve is classified according to function: water electromagnetic valve, steam electromagnetic valve, refrigeration electromagnetic valve, cryogenic electromagnetic valve, gas electromagnetic valve, fire electromagnetic valve, ammonia electromagnetic valve, gas electromagnetic valve, liquid electromagnetic valve, miniature electromagnetic valve, pulse electromagnetic valve, hydraulic electromagnetic valve normally open electromagnetic valve, oil electromagnetic valve, DC Solenoid Valve, high-pressure electromagnetic valve, explosion-proof electromagnetic valve, etc.
Type selection of electromagnetic valve
The selection basis of electromagnetic valve
The selection of electromagnetic valve should first follow the four principles of safety, reliability, applicability and economy in turn, second according to the on-site conditions of six aspects (I .e. pipeline parameters, fluid parameters, pressure parameters, electrical parameters, selection of action mode and special requirements).
The selection basis of electromagnetic valve:
1. Select the electromagnetic valve according to the pipe parameters: diameter specification (I .e. DN), interface mode.
- 1) Determine the diameter (DN) size according to the field pipe inner diameter size or flow rate requirements;
- 2) Interface mode is General> DN50 flange interface should be selected, ≤dn50 can be selected freely according to user needs.
2. Select the electromagnetic valve according to the fluid parameters: material, temperature group.
- 1) Corrosive fluid: corrosion-resistant electromagnetic valve and all stainless steel are appropriate; Edible ultra-clean fluid: food grade stainless steel electromagnetic valve is appropriate;
- 2) High temperature fluid: choose electromagnetic valves made of high temperature resistant electrical materials and sealing materials, and choose piston type;
- 3) Fluid state: large to gaseous, liquid or mixed state, especially when the diameter is greater than DN25, it must be distinguished;
- 4) Fluid viscosity: usually can be arbitrarily selected under 50cSt, if it exceeds this value, the high viscosity electromagnetic valve should be selected.
3. Choose the electromagnetic valve according to the pressure parameters: principle and structural variety.
- 1) Nominal pressure: this parameter has the same meaning as other general valves, which is determined according to the nominal pressure of the pipeline;
- 2) Working pressure: if the working pressure is low, then it must use the direct-action or step-by-step direct-action principle; when the minimum working pressure difference is more than 0.04Mpa, the direct-action, step-by-step direct-action and pilot-action modes.
4. Electrical selection voltage specifications should be preferred to AC220V and DC24 as far as possible.
5. According to the length of working time to choose: normally closed, normally open, or sustainable power.
- 1) When the electromagnetic valve needs to be turned on for a long time and lasts longer than the closed time, normally open type should be selected;
- 2) If the opening time is short or the opening and closing time is not long, the normally closed type is selected;
- 3) However, some working conditions for safety protection, such as furnace and kiln flame monitoring, cannot be selected for normally open type, and should be selected for long-term power-on type.
6. Select auxiliary functions according to environmental requirements: explosion-proof, non-return, manual, waterproof fog, water pouring and diving.
Selection principle of electromagnetic valve
According to the safety of electromagnetic valve:
1. Corrosive medium: it is appropriate to use plastic king electromagnetic valve and all stainless steel; For strong corrosion medium, it must use isolation film chip. Neutral Medium, the electromagnetic valve with copper alloy as the valve shell material should also be used, otherwise, the rust and dust in the valve shell often fall off, especially in the case of not frequent movements. Ammonia valve can not use copper material.
2. The explosive environment: must use the corresponding explosion-proof grade products, outdoor installation or dust occasions should use waterproof, dustproof varieties.
3. The nominal pressure of the electromagnetic valve should exceed the highest working pressure in the pipe.
According to the applicability of electromagnetic valve:
1. Medium characteristics
- 1) Electromagnetic valves of different varieties are selected in the mass gas, liquid state or mixed state;
- 2) Medium temperature different specifications of products, otherwise the coil will burn, the seal is aging, seriously affecting the service life;
- 3) Medium viscosity, usually below 50cSt. If it exceeds this value, when the diameter is greater than 15mm, use multi-function electromagnetic valve; When the diameter is less than 15mm, use high viscosity electromagnetic valve.
- 4) When the cleanliness of media is not high, it should be equipped in front of the electromagnetic valve. When the pressure is low, the direct action diaphragm electromagnetic valve can be selected;
- 5) If the medium flows directionally and does not allow back flow, two-way flow is required;
- 6) Medium temperature should be selected within the allowable range of electromagnetic valve.
2. Pipeline parameters
- 1) Select the valve port and model according to the medium flow requirement and pipeline connection mode;
- 2) According to the flow and valve Kv value to select the nominal diameter, also can choose the same pipe inner diameter;
- 3) Working pressure difference: if the minimum working pressure difference is above 0.04Mpa, it can be selected with indirect pilot type; If the minimum working pressure difference is close to or less than zero, it must be selected with direct or step-by-step direct type.
3. Environmental conditions
- 1) The highest and lowest temperatures of the environment should be within the allowable range;
- 2) Waterproof electromagnetic valve should be selected for occasions with high relative humidity in the environment and water droplets and rain;
- 3) In the environment, special varieties should be selected for occasions such as vibration, bumps and shocks, such as marine electromagnetic valves;
- 4) The use in corrosive or explosive environment should be selected in priority according to the safety requirements;
- 5) If the environment space is restricted, multi-function electromagnetic valve is needed, because it saves the bypass and three manual valves and is convenient for online maintenance.
4. Power supply conditions
- 1) Select AC and DC Solenoid valves according to the type of power supply. Generally speaking, AC power supply is convenient to use;
- 2) As far as possible, choose AC220V.DC24V as the voltage specification;
- 3) The fluctuation of power supply voltage is usually +%10%.-15% for AC, and about +%10 for DC. If it is too poor, voltage stabilization measures shall be taken;
- 4) The forehead current and power consumption should be selected according to the capacity of power supply. Attention should be paid to the high VA value when the AC starts, and the indirect conductive electromagnetic valve should be selected first when the capacity is insufficient.
5. Control accuracy
1) Ordinary electromagnetic valve has only two positions of on and off. When the control accuracy requires high and stable parameters, multi-position electromagnetic valve is required;
2) Action Time: refers to the completion time when the electrical signal is connected or cut off to the main valve;
3) leakage volume: the leakage volume value given on the sample is commonly used economic level.
According to the reliability of electromagnetic valve:
- 1. Working life, this item is not included in the factory test item belongs to the type test item. In order to ensure the quality, famous brand products from regular manufacturers should be selected.
- 2. Working system: it is divided into three types: long-term working system, repeated short-term working system and short-term working system. Normally open electromagnetic valve is better for the situation that the valve is only closed for a short time.
- 3. When the working frequency and operating frequency are required to be high, the structure should be optimized for direct-acting electromagnetic valve, and the power supply is preferred for communication.
- 4. Operational reliability: strictly speaking, this test has not yet been officially listed in the professional standard of electromagnetic valve in China, and in order to ensure the quality, famous brand products of regular manufacturers should be selected. In some occasions, the action time is not too much, but the reliability requirements are very high, such as fire protection, emergency protection, etc., must not be treated lightly. Especially important, two dual-use insurance should also be adopted.
One of the scales it chooses, but it must be an economy based on safety, application and reliability.
Economical Efficiency is not only the price of a product, its function and quality, as well as the cost of installation and maintenance and other accessories should be given priority.
More importantly, a electromagnetic valve takes up very little in the whole automatic control piping system and even in the production line in the whole automatic control ping system. If you want to choose small and cheap, it will cause huge damage.
Installation of electromagnetic valve
- 1. When installing, pay attention to the arrow on the valve body should be consistent with the medium flow direction. Do not install it in a place where there is direct dripping or splashing water. The electromagnetic valve should be installed vertically upward;
- 2. The electromagnetic valve should be guaranteed to work normally within the fluctuation range of 15%-10% of the positive voltage;
- 3. After the installation of the electromagnetic valve, there shall be no reverse pressure difference in the pipeline. And need to power up several times to make it warm before it can be formally put into use;
- 4. The pipeline should be thoroughly cleaned before the installation of the electromagnetic valve. The medium passed in should be free of impurities. Filter installed before valve;
- 5. When the electromagnetic valve fails or is cleaned, the bypass device should be installed to ensure the system to continue running.
Troubleshooting of electromagnetic valve
Solenoid Valve does not work after power on.
- Check whether the power wiring is bad → re-connect the wiring and the connector.
- Check whether the power supply voltage is in the working range-→ adjust to the normal position range.
- Whether the coil is descaling → rewelded.
- Coil short circuit → replace coil.
- Whether the operating pressure difference is inappropriate → adjust the pressure difference → or replace the proportional electromagnetic valve.
- Fluid temperature is too high → replace proportional electromagnetic valve.
- If there are impurities blocking the main valve core and moving iron core of the electromagnetic valve → clean, if there is any sealing damage, the seal should be replaced and the filter should be installed.
- The viscosity of the liquid is too large, the frequency is too high and the life has arrived → replace the product
Solenoid valve can not be closed.
- The seal of the main spool or iron moving core is damaged → replace the seal.
- Whether the temperature and viscosity of the fluid are too high → replace the corresponding electromagnetic valve.
- There are impurities entering the electromagnetic valve production valve or moving iron core → cleaning.
- The spring life has reached or deformed → replace.
- Orifice balance hole blocked → clean in time.
- The working frequency is too high or the service life is reached → change the product or update the product.
- Internal leakage → check whether the seal is damaged and whether the spring is assembled poorly.
- External leakage → The connection is loose or the seal is broken → tighten the screw or replace the seal.
- There is noise when the power is turned on → the strong firmware on the head is loose and tightened. Voltage fluctuation is not within the allowable range, adjust the voltage. Iron core suction surface impurities or unevenness, timely cleaning or replacement.
Sealing Materials for electromagnetic valve
There are currently three most commonly used sealing materials for electromagnetic valves.
NBR nitrile rubber
Made of butadiene and acrylonitrile by emulsion polymerization, nitrile rubber is mainly produced by low-temperature emulsion polymerization, with excellent oil resistance, high wear resistance, good heat resistance and strong adhesion. The disadvantages are poor low temperature resistance, poor ozone resistance, poor electrical performance and slightly lower elasticity.
In addition, it also has good water resistance, air tightness and excellent bonding performance. Widely used in making all kinds of oil-resistant rubber products, various oil-resistant gaskets, gaskets, bushings, flexible packages, flexible rubber tubes, printing and dyeing rubber rolls, cable rubber materials, etc, copying and other industries have become essential elastic materials.
Nitrile rubber has excellent oil resistance, its oil resistance is second only to polysulfide rubber and fluorine rubber, and has wear resistance and air tightness. The disadvantage of nitrile rubber is that it is not resistant to ozone and aromatic, halogenated hydrocarbons, ketones and ester solvents, and is not suitable for insulating materials.
Nitrile rubber is mainly used to make oil-resistant products, such as oil-resistant tubes, adhesive tapes, rubber diaphragms and large oil sac, etc. It is commonly used to make various oil-resistant molded products, such as o-rings, oil seals, leather bowls, diaphragms, valves and, it is also used to make rubber plate and wear-resistant parts.
Epdm rubber (EPDM)
Epdm rubber is a terpolymer of ethylene, propylene and unconjugated diolefins. Commercial production began in 1963. The annual world consumption is 800,000 tons. The main characteristic of EPDM is its superior oxidation resistance, ozone resistance and corrosion resistance. Since ethylene propylene monomer belongs to polyolefin family, it has excellent vulcanization characteristics. Of all rubber, EPDM has the lowest specific gravity. It can absorb a large amount of stuffing and oil and has little influence. Therefore, low-cost rubber compounds can be made.
Molecular structure and characteristics: EPDM is a terpolymer of ethylene, propylene and unconjugated diolefins. Diolefins have a special structure, only one of the two bonds can copolymerization, unsaturated double bonds are mainly used as the Junction chain. The other unsaturated will not become the main chain of the polymer, only the side chain. The main polymer chain of EPDM is completely saturated. This feature makes EPDM resistant to heat, light, oxygen, especially ozone. EPDM is nonpolar in nature, with low resistance and water absorption to Polar solutions and chemicals and good insulation characteristics.
- 1. Low density and high filling;
- 2. Aging resistance;
- 3. Corrosion resistance;
- 4. Water steam resistance performance;
- 5. Performance of over-water resistance;
- 6. Electrical performance;
- 7. Elasticity;
- 8. Adhesive.
VITON fluororubber (FKM)
Rubber containing fluorine in the molecule, according to the fluorine content, the monomer structure and there are various types; Hexafluorized fluoroplast rubber has better high temperature resistance than silicone rubber, chemical resistance, most oil and solvent resistance (ketone, except ester), weather resistance, ozone resistance is good, but cold resistance is poor; Generally widely used in automobile locomotive, B and other products, chemical plant seals, operating temperature range-20℃ ~ 260℃, when the low temperature requirement is used, the low temperature resistant type can be selected and applied to-40 ℃, but the price is higher.
The difference between electric valve and electromagnetic valve
- The electromagnetic valve is an electromagnetic coil which is attracted by the magnetic force after being energized to overcome the pressure of the spring and drives the spool action. The electromagnetic coil has a simple structure and a cheap price, and can only be switched;
- The electric valve drives the valve stem through the electric motor, driving the valve element action, and the electric valve consists of (shut-off valve) and regulating valve. The shut-off valve is two-position operation, that is, all-on and all-off. The regulating valve is to install an electric valve locator on it to stabilize the valve dynamically at one position through closed-loop adjustment.
Use comparison of electric valve and electromagnetic valve
Solenoid valve: used for switch control of liquid and gas pipeline, which is two-bit DO control. It is generally used for the control of small pipelines.
Electric valve: used for analog adjustment of medium flow in pipelines of liquid, gas and wind systems, is AI control. In the control of large valves and wind systems, electric valves can also be used for two-position switch control.
Solenoid valve: it can only be used as switching value, DO control, and can only be used for small pipe control. It is common in pipes of DN50 and below.
Electric valve: AI feedback signals can be controlled by DO or AO, which are more common in large pipelines and air valves.
The electromagnetic valve is driven by the coil and can only be turned on or off, and the action time is short.
The drive of the electric valve is generally a motor. It takes a certain amount of time to complete the on or off action, which can be adjusted.
Nature of work:
The electromagnetic valve generally has a small flow coefficient and a small working pressure difference. For example, the flow coefficient of general 25-caliber electromagnetic valve is much smaller than that of 15-caliber electric ball valve. The drive of the electromagnetic valve is through the electromagnetic coil, which is easily damaged by voltage impact. It is equivalent to the function of the switch, that is, the two functions of turning on and off.
The drive of the electric valve is generally motor, which is more resistant to voltage impact. The electromagnetic valve is quick on and quick off, generally used in small flow and small pressure, requiring the electric valve to be opposite to the place where the switching frequency is high. The opening of the electric valve can control the states of on, off, half open and half off, which can control the flow of the medium in the pipeline, but the electromagnetic valve cannot meet this requirement.
Generally, the electromagnetic valve can be reset when the power is off, and the electric valve needs to add a reset device for such a function.
Solenoid valve is suitable for some special process requirements, such as leakage, special fluid medium, etc., the price is more expensive.
Electric valves are generally used for adjustment, and there are also switching values, such as: the end of the wind turbine coil.
Main features of electromagnetic valve
1. The external leakage is blocked, the internal leakage is easy to control, and it is safe to use.
Internal and external leakage is a safety hazard. Other self-control valves usually stretch out the valve rod, and the running or moving of the valve element is controlled by electric, pneumatic and hydraulic actuators. This is to solve the problem of external leakage of the dynamic seal of the valve stem with long-term action. Only the electromagnetic valve uses magnetic force to act on the iron core sealed in the magnetic sleeve of the electric regulating valve. There is no dynamic seal, so the external leakage is easy to plug. The torque control of the electric valve is not easy, and it is easy to generate internal leakage, and even pull off the head of the valve rod; The structure type of the electromagnetic valve is easy to control internal leakage until it drops to zero. Therefore, the electromagnetic valve is particularly safe to use, especially suitable for corrosive, toxic or high and low temperature media.
2. The system is simple and the price for connecting to the computer is low.
The electromagnetic valve itself is simple in structure and low in price, which is easier to install and maintain than other types of actuators such as regulating valves. What is more significant is that the automatic control system is much simpler and the price is much lower. Since the electromagnetic valve is controlled by switch signal, it is very convenient to connect with industrial control computer. In today’s computer popularization, the price of the sharp decline in the era, the advantages of the electromagnetic valve is more obvious.
3. Small express power and lightweight appearance.
The response time of the electromagnetic valve can be as short as a few milliseconds, and even the pilot electromagnetic valve can be controlled within tens of milliseconds. Due to the self-formed circuit, it is more sensitive than other self-control valves. The power consumption of the properly-designed electromagnetic valve coil is very low, and it is an energy-saving product; It can also be achieved that only trigger the action and automatically maintain the valve position, and usually do not consume electricity at all. The outer size of the electromagnetic valve is small, which not only saves space, but also is light and beautiful.
4. Limited adjustment accuracy, limited applicable medium.
The electromagnetic valve usually has only two states of switch. The valve core can only be in two limit positions and cannot be continuously adjusted, so the adjustment accuracy is still limited.
The electromagnetic valve has a higher requirement for the cleanliness of the media, and the media containing particles are not applicable. If it is an impurity, it must be filtered first. In addition, viscous media cannot be applied, and the range of media viscosity applicable to specific products is relatively narrow.
5. Various models and wide uses.
Although the electromagnetic valve has congenital deficiencies, its advantages are still very prominent, so it is designed into a variety of products to meet various needs and has a very wide range of uses. The progress of electromagnetic valve technology also focuses on how to overcome the congenital deficiencies and how to better play the inherent advantages.
Relevant regulations on the selection of electromagnetic valves
1. Key points of product selection
- 1) The main control parameters selected for the electromagnetic valve include diameter, design nominal pressure, medium allowable temperature range, interface size, etc.
- 2) The electromagnetic valve is used to push the opening and closing of the valve with an electromagnet. It is usually used for two-bit control with a diameter of less than 40mm, especially for connecting, cutting off or converting the gas path, liquid path, etc.
- 3) The sealing performance of the valve is one of the main indexes for assessing the quality of the valve. The sealing performance of the valve mainly includes two aspects, internal leakage and external leakage. Internal leakage refers to the sealing degree between the valve seat and the closing piece to the medium. The leakage refers to the leakage of the packing part of the valve stem, the leakage of the middle mouth gasket and the leakage of the valve body caused by the casting defect. Leakage is not allowed to occur.
- 4) The main advantages of the electromagnetic valve are small size, reliable movement, convenient maintenance and low price. When choosing, pay attention to choose normally open or normally closed type according to the process requirements.
2. Key points of construction and installation
- 1) The installation position and height of the valve must meet the requirements of the port direction design, and the connection should be firm and tight.
- 2) The appearance inspection must be carried out before the installation of the valve, and the nameplate of the valve should comply with the provisions of the current national standard GB12220 “general valve logo.
3. Executive standards
China standard for electromagnetic valves:
- China electromagnetic valve product industry standard “electromagnetic valve for industrial process control system (JB/T7352-2010)”.
- GB/T13927-92 “universal valve pressure test”.
- JB/T8528-1997《 specification of ordinary valve electromotion device.
- GB12220-89 “general valve logo”.
- GB50243-2002 code for acceptance of construction quality of ventilation and air conditioning works.
- GB50242-2002 code for acceptance of construction quality of water supply, drainage and heating engineering.
Common types of electromagnetic valves.
- 2-position 2-way universal valve
- Hot water/steam valve
- 2-position 3-way valve
- 2-position 4-way valve
- 2-position 5-way valve
- Intrinsically safe explosion-proof electromagnetic valve
- low power electromagnetic valve
- Manual reset electromagnetic valve
- Precision miniature valve
- Valve position indicator
Common failures of electromagnetic valve
The electromagnetic valve is composed of an electromagnetic coil and a magnetic core and is a valve body containing one or several holes. When the coil is powered on or off, the operation of the magnetic core will cause the fluid to pass through the valve body or be cut off to achieve the purpose of changing the direction of the fluid. Electromagnetic parts of electromagnetic valve consist of fixed iron core, moving iron core, coil and other parts; Part of valve body consists of slide valve core, slide valve sleeve, spring base and so on. The electromagnetic coil is directly installed on the valve body, and the valve body is closed in the sealed tube to form a concise and compact combination. The electromagnetic valves commonly used in our production include two-position three-way valve, two-position four-way valve, two-position five-way valve, etc. Here, let’s talk about the meaning of the two: for the electromagnetic valve, it is charged and lost electricity, and for the valve controlled, it is open and closed.
The failure of the electromagnetic valve will directly affect the operation of the switching valve and the regulating valve. The common failure is that the electromagnetic valve does not work. The following aspects should be investigated:
- 1. If the electromagnetic valve connector ends loose or the thread ends fall off, the electromagnetic valve shall not be charged and the thread ends can be fastened.
- 2. If the electromagnetic valve coil is burnt out, the wiring of the electromagnetic valve can be removed and measured with a multimeter. If it is open, the electromagnetic valve coil will burn out. The reason is that the coil is affected by moisture, which causes poor insulation and magnetic leakage, resulting in excessive current in the coil and burning, so it is necessary to prevent rainwater from entering the electromagnetic valve. In addition, the spring is too strong, the reaction force is too large, the number of turns of the coil is too small, and the suction is not enough to burn the coil. When the emergency treatment, the manual button on the coil can be switched from “0” to “1” when it is working normally, so that the valve is opened.
- 3. The electromagnetic valve gets stuck: the cooperation gap between the sliding valve sleeve of the electromagnetic valve and the valve element is very small (it is generally a single-piece assembly when it is less than 0.008mm). The treatment method can be used to poke the steel wire through the small hole in the head to make it spring back. The fundamental solution is to remove the electromagnetic valve, take out the valve core and its sleeve, and clean it with CCI4 to make the action in the valve core’s sleeve flexible. When disassembling, pay attention to the assembly sequence and external wiring position of each part, so as to reassemble and wiring correctly. Also check whether the oil injection hole of the oil sprayer is blocked and whether the lubricating oil is enough.
- 4. Air leakage and air leakage will cause insufficient air pressure, which makes it difficult to start and close the forced valve. The reason is that the sealing gasket is damaged or the slide valve is worn and causes several cavity to run air. When dealing with the electromagnetic valve failure of the switching system, an appropriate time should be selected to deal with it when the electromagnetic valve is out of power. If it cannot be handled within a switching gap, the switching system can be paused, take care.
Source: China Valve Manufacturer – Yaang Pipe Industry Co., Limited (www.steeljrv.com)
(Yaang Pipe Industry is a leading manufacturer and supplier of nickel alloy and stainless steel products, including Super Duplex Stainless Steel Flanges, Stainless Steel Flanges, Stainless Steel Pipe Fittings, Stainless Steel Pipe. Yaang products are widely used in Shipbuilding, Nuclear power, Marine engineering, Petroleum, Chemical, Mining, Sewage treatment, Natural gas and Pressure vessels and other industries.)
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