How to correctly adjust the valve's electric device

Writer： admin Time：2024-06-26 14:46:54 Browse：5℃

In industrial enterprises, especially urban waterworks in the process of production and water supply, the use of a large number of ordinary gate valves, butterfly valves, liquid-controlled butterfly valves, etc., to control the production of piped water, is a water supply enterprises, a major equipment. In the use of various types of valves for the gate valve in larger quantities. In this paper, we will discuss how to adjust the electric valve motorized device.

    Electric gate valve by the valve electric device and gate valve supporting the composition of electric gate valve, to control the opening and closing of the gate valve. It can be operated on-site or at a distance. Valve electric device consists of motor, reducer, torque limiting mechanism, stroke control mechanism, manual and electric conversion mechanism, opening degree indication mechanism and electrical controller. Electric gate valve electric device if not properly adjusted, shorten the service life of the gate valve; heavy lead to valve cast iron shell fracture, control motor burned out and flooding pump room and other serious accidents. Therefore, in order to ensure safe and uninterrupted water supply, must be carefully adjusted electric gate valve electric device to ensure that the electric gate valve start, close smoothly. Here are two ways to adjust the electric gate valve:

    1, torque limiting mechanism adjustment

    Electric gate valve used in different places due to the gate ends of the water pressure difference or air pressure difference (when the gate valve is closed), the torque limiting mechanism can be adjusted appropriately. In the electric gate valve gate at both ends of the direction of the water pressure or air pressure difference is low, the torque limiting mechanism should be adjusted to a lower torque, in the use of HZ series valve electric device, as long as the adjustment of the torque limiting mechanism of the adjustment of the plucking plate and the distance between the contact plate to achieve (see the adjustment instructions). The scale is marked on the scale plate, and the larger its scale value is, the larger the torque value is. The greater the water pressure difference or air pressure difference between the two ends when the electric valve gate is closed, the greater the adjusted torque value is required, and vice versa is small. The above series are adjusted in the same way. When adjusting the ZD series valve electric device (see Fig. 4), remove the side cover of the box, adjust the torque limiting mechanism, loosen the set screw in the adjusting nut, loosen the adjusting nut, relax the button torque spring and put it to the loosest position, then tighten the set screw in the adjusting nut and fix the adjusting nut. Note that the top of the setscrew must fall in the shaft groove, if the top is not exactly aligned with the shaft groove, just turn the adjusting nut a little in the direction of the compression spring to align it with the shaft groove setscrew. Then put the side cover on, adjust the opening valve. If the torque limiting mechanism movement, the spring is too loose to adjust the tightening until no action. This will enable the torque limiting mechanism to work at a lower torque to ensure that the electric gate valve due to the failure of the trip control mechanism, or other reasons for super-torque, the torque limiting mechanism reliable action, and cut off the power supply to the motor, to protect the valve from damage. In some places the use of electric gate valves do not have to adjust the closing too tight, adjusted to manually shut down and then loosened back to half a circle (or a circle) position is good, (or no water or gas leakage is good).

    When the electric gate valve is installed in the outlet water pressure difference (or air pressure difference) when used in large places, the torque limiting mechanism should be adjusted to the appropriate opening and closing torque. Such as installed in the pump room of the outlet gate valve, in the pump after starting, the gate valve is not opened when the outlet water pressure is large, at this time the larger the caliber of the outlet gate valve, the larger the torque used to open the gate valve. Especially when there is no pressure in the pipeline, the gate of the gate valve is subjected to unidirectional pressure is the largest, then the adjusting nut compression spring, adjusted to the normal opening and closing of the gate valve, torque limiting mechanism does not act until. Electric gate valve used in the pump room in the adjustment must be adjusted to the full open and closed position, otherwise it is easy to make the sealing surface of the gate valve damage caused by water leakage. Because the electric gate valve installed in the place from the pump outlet near the water flow rate is high and unstable, at this time, such as the gate valve is not fully open and part of the gate due to the impact of the water flow caused by the front and back fluctuation, so that the sealing surface of the gate wear and tear, the formation of grooves and leakage affect the service life of the valve. In addition, should try to avoid the use of electric gate valve to regulate the flow, otherwise it is easy to damage the sealing surface of the gate valve. In addition, in recent years, frequency conversion speed control technology is developing rapidly, pump flow regulation should use frequency conversion speed control technology to achieve energy saving and improve pump efficiency.

    2 electric gate valve "open, close" position adjustment

    Adjust the opening and closing of the electric gate valve. According to the manufacturers of the adjustment requirements are to manually close the valve to the "fully closed" position or "fully open" position. If the requirements of this large-diameter gate valve manually closed to open the time spent more, but also very laborious. Introduced here is a new method of adjustment: if you know the adjusted gate valve stem tooth distance, in the adjustment of the electric gate valve will be very convenient to adjust. Now the domestic production of valves in DN400-DN600 caliber gate valve stem pitch is generally 8mm, DN600 caliber gate valve stem pitch is generally 10mm. if possible to ask the gate valve manufacturer stem pitch. In the adjustment of the valve electric device, if you know the position of the gate valve in advance, such as knowing the gate valve is in the fully closed position, then first adjust the "fully closed" position. First of all, manually turn the gate valve in the direction of opening some, such as half a turn or a turn of the valve stem. Then press the "open" button on the power supply. Check the steering, if you press the button to open the valve, the valve stem steering and manually open the valve stem steering consistent, indicating that the phase sequence of the motor and the direction of the valve's electrical controller is the same, at this time you can first adjust the gate valve travel control mechanism, adjusted to the fully closed position, fully closed position adjustment is complete, you can adjust the gate valve fully open position. At this point in the opening of the gate valve, count the number of turns of the gate valve stem will know whether to "fully open" position. If it is DN500 electric gate valve, the valve stem tooth distance is 8mm, the valve stem to turn a circle open 8mm, fully open the gate valve plate to make an upward movement of 500mm, so fully open the valve stem needs to be rotated 500/8 = 62.5 laps. At this time, press the button to open the valve to 63 turns of the valve to the "open" position, adjust the valve electric device travel controller, so that the "open" position of the microswitch action can be. Thereafter, the electric gate valve can be closed, opened to check once, the end of the adjustment. If the electric gate valve in the open position before adjustment, you should first adjust the open position, the steps described above.

    3 Note after adjustment

    One year after the use of electric gate valve, to check whether the tightening screw in the adjusting nut of the torque limiting mechanism has loosened or fallen off. In particular, ZD series valve electric device (see Figure 4), some electric gate valve in use occurred at the bottom of the gate valve by the top of the valve plate broken or the upper part of the fixed electric device of the coupling fascia plate was cracked. Why have a torque limiting mechanism, over torque when not action, not cut off the power supply, the reason is that the torque limiting mechanism in the adjusting nut of the tightening screw due to loosening out so that the adjusting nut for a long time to tighten the spring, until the spring is crushed, so that the torque limiting mechanism loses its role, does not play a role in the protection, resulting in damage to the electric gate valve accident. Therefore, it is necessary to check once a year to see if the set screw has fallen out, if the set screw is loosened, it should be tightened in time, and find out the reason for the fall off off the reinforcement.

    Manual - electric conversion handle requires flexible mechanical mechanism, trigger freely, when the trigger to manual, to ensure that the power supply is cut off, so as to avoid accidents when the failure.

    For a long time rarely open, close the gate valve to switch regularly to ensure that the use of normal work. (It is recommended that it is best to turn once every three months).