Do you know that SMC solenoid valves are prone to these malfunctions?

Do you know that SMC solenoid valves are prone to these malfunctions?

SMC solenoid valves and these small components. But the chiller unit is a large system that requires the coordination and smooth cooperation of various components in order to achieve normal operation of the chiller unit. If we consider the chiller unit as the human body, then the compressor evaporator can be seen as the human heart and hands, while the shut-off valve and regulating valve can be seen as the various joints of the human body, playing a crucial role in maintaining the normal operation of the entire system. Today, let's talk about the common malfunctions of globe valves and regulating valves.

The valve body leakage of SMC solenoid valves is mostly made of steel castings, which may form casting sand holes during the process, causing the valve to leak refrigerant during use.

2. The SMC solenoid valve stem is twisted and the valve material is compressed too tightly, resulting in a lack of lubrication and dry friction; Improper use of tools to open and close the wide door during operation, excessive force applied; The refrigerator at the valve stem is too thick; Long term use causes the valve stem to gradually wear, bend, or even break. The slope material of the root canal has been worn out and has experienced tipping over.

3. The valve core of SMC solenoid valve fell off due to the damage of the yellow card on the valve core, causing the valve core to detach from the valve stem and the surrounding core to lose control. The valve is no longer able to open and close normally.

4. Welding, iron lubrication, and sand impurities in the SMC solenoid valve seat and core damage system There is no clean discharge in the refrigeration system Accumulated at the turning point of the valve seat. When the valve is opened and closed, the alloy on the valve core and the sealing surface of the valve seat may have spots and scratches due to foreign objects being embedded or squeezed. Apply mud inside the valve, lose its sealing function, apply excessive force during operation, or use excessive tools for switching valves The alloy on the valve core is pressed into deep pits, so the closure is not tight. Due to the influence of high temperature on the sealing surface, the hardness of the bearing alloy on the valve core decreases, resulting in severe wear and loss of sealing function.

SMC solenoid valve converts the current signal into corresponding linear displacement, automatically controls the opening of the regulating valve, and achieves continuous adjustment of process parameters such as pressure, flow rate, temperature, and liquid level of the fluid in the pipeline. Widely used for controlling gas, liquid, and vapor media, especially suitable for working environments where the allowable pressure difference is small and the allowable leakage is also small, and the pressure difference is not significant.

SMC solenoid valve has a compact structure, light weight, sensitive action, small pressure drop loss, large valve capacity, flow characteristics, and easy maintenance, which can be used in harsh working conditions. Multi spring actuators have low height, light weight, and easy equipment.

Before installing SMC solenoid valves, the following points should be noted:

1. It should be installed vertically on a horizontal pipeline. In special cases where horizontal or inclined installation is required, support should generally be added.

2. It should be installed near the ground or floor for maintenance and repair purposes; For those equipped with valve positioners or handwheel mechanisms, sufficient space should be provided for easy observation, adjustment, and operation.

3. Generally, a bypass pipeline is set up to switch to manual operation in case of automatic control system failure or maintenance of regulating valves, so as not to stop.

4. After installing the handwheel mechanism, the bypass pipeline can also be omitted for manual operation, and it is also used to limit the opening of the valve. When stopped, the handwheel mechanism must be restored to its original neutral position to facilitate normal operation of the self-control.

5. During installation, the flow direction of the medium should be consistent with the direction indicated on the valve body.

6. Before installation, the SMC solenoid valve should be cleaned of dirt and welding slag in the pipeline. After installation, the regulating valve should be fully opened, and the pipeline and valve should be cleaned and the sealing of each connection should be tested.

When the temperature of the controlled medium of SMC solenoid valve changes, the volume of the temperature sensing liquid in the sensor expands or contracts. When the temperature of the controlled medium is higher than the set value, the temperature sensing liquid expands, pushing the valve core downwards to close the valve and reduce the flow rate of the heat medium; When the temperature of the controlled medium is lower than the set value, the temperature sensing liquid contracts, and the reset spring pushes the valve core to open, increasing the flow rate of the heat medium.

Before using SMC solenoid valves, the following items should be understood:

1. The temperature of the product has been set according to the user's requirements and usage before leaving the factory. After closing the bypass, the user can directly use this product.

2. It is recommended to start the cycle pump first to gradually raise the temperature of the entire heated water system. When the temperature approaches the set temperature, open all shut-off valves.

When initially activated, there may be some temperature fluctuations, but after a short period of operation, a stable working state can be achieved. The temperature indicator standard plate on this product is the factory set temperature, which is provided for users to refer to when adjusting. It does not represent the actual temperature, and the actual temperature should be based on the thermometer reading on site.

4. If there is a deviation in temperature during use or if the user needs to change the set temperature, it can be adjusted. Insert the adjustment wrench into the adjustment hole of the sliding temperature knob. When adjusting from low temperature to high temperature, turn counterclockwise to adjust the temperature lower. Then turn the adjustment wrench clockwise to adjust.

When the system stops running, first close the inlet shut-off valve of the heat medium, and then close the system circulation pump.

SMC solenoid valves provide a favorable working environment for control. Installing a self operated differential pressure control valve in front of the heat exchanger can prevent excessive water flow rate and pressure reduction, thereby extending its lifespan.

Slowly close the main valve to prevent damage to the valve disc and seat due to impact.

SMC solenoid valve is a general heavy hammer safety valve (which can also be a spring type safety valve). The main safety valve has a piston chamber, and the piston and valve core are installed on the same valve stem. The valve core is pressed against the valve seat by steam pressure and the upward tension of the spring. When the boiler pressure exceeds the specified value, the pulse valve first opens, and the discharged steam is sent to the upper part of the main safety valve piston through the pulse tube. With the help of steam pressure, the piston moves downward, driving the valve core to leave the valve seat downward, and the main safety valve opens to discharge steam.

What are the performance characteristics of SMC solenoid valves?

1. By balancing the pressure of the valve disc with a lever and a heavy hammer, the valve is sealed, and the position and weight of the heavy hammer are moved to achieve the required popping pressure.

2. The sealing material is made of iron-based chromium nickel stainless steel by welding, and the valve disc is heat-treated to improve wear resistance and erosion resistance.

3. The upper part of the valve is equipped with an electromagnet for opening and closing, and the mechanical and electrical actions do not interfere with each other.

SMC solenoid valves are mainly used in power plant boilers, various pressure vessels, and temperature and pressure reduction equipment to prevent timely pressure relief when the equipment pressure exceeds the allowable value, ensuring the safe operation of the equipment. A long distance should be maintained between the outlet pipe of the safety valve and the inlet pipe of the main safety valve. The distance between the electric contact pressure gauge and the inlet pipe of the main safety valve should not be less than 5 times the diameter of the inlet pipe of the main safety valve;

To avoid affecting the correctness of the operation of the electric contact pressure gauge and pulse safety valve due to exhaust steam when the main safety valve is activated. This safety valve consists of a main valve and an auxiliary valve. The main valve is driven by the pulse action of the auxiliary valve, and its structure is complex. It is usually only suitable for boilers and pressure vessels with large safety release capacity.