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At DELCO, we understand the importance of customer satisfaction and strive to meet the unique needs of every client. As a reliable valve supplier, we are committed to providing excellent customer service and high-quality products to ensure optimal performance and longevity. By choosing DELCO as your trusted control air supplier, you can benefit from customized valve assemblies designed specifically to meet your requirements, enhancing efficiency and reducing downtime.
Common causes and solutions of internal leakage in electric control valves
Electric control valves have been increasingly widely used in various industrial control systems due to their high control accuracy and easy installation and debugging. However, there are also some issues that plague on-site instrument personnel during use, such as valve leakage problems. Here we will explore the common causes and solutions of internal leakage in electric control valves, hoping to provide some assistance to on-site maintenance personnel in factories.
1.The zero position setting of the actuator is inaccurate and has not reached the fully closed position of the valve. Adjustment method: 1) Manually close the valve (it must be confirmed that it has been completely closed); 2) Manually close the valve with more force, until it cannot be turned with a little bit of force; 3) Twist back (in the direction of valve opening) by half a circle; 4) Then adjust the limit.
2. The valve is a downward push closure type, and the thrust of the actuator is not strong enough. When there is no pressure, it is easy to reach the fully closed position during debugging. However, when there is downward thrust, it cannot overcome the upward thrust of the liquid, so it cannot be closed in place. Solution: Replace the high thrust actuator or use a balanced valve core to reduce the unbalanced force of the medium.
1、Internal leakage caused by the manufacturing quality of electric control valves
The manufacturer of the regulating valve did not strictly control the valve material, processing technology, assembly technology, etc. during the production process, resulting in unqualified grinding of the sealing surface and incomplete removal of products with defects such as pitting and sand holes, causing internal leakage of the electric regulating valve. Solution: Reprocess the sealing surface.
2、The control part of the electric regulating valve affects the internal leakage of the valve
The traditional control method of electric control valves is through mechanical control methods such as valve limit switches and over torque switches. Due to the influence of environmental temperature, pressure, and humidity on these control components, the valve positioning is inaccurate, and objective factors such as spring fatigue and uneven thermal expansion coefficient cause internal leakage of electric control valves. Solution: Adjust the limit again.
3、Internal leakage caused by debugging issues of electric control valve
Due to the influence of processing and assembly technology, electric control valves generally have the phenomenon of being unable to open after being manually closed tightly. If the stroke of the electric control valve is adjusted smaller by the action position of the upper and lower limit switches, an unexpected state of the electric control valve not closing tightly or the valve not opening can occur; If the stroke of the electric control valve is adjusted larger, it will cause the over torque switch protection action; If the action value of the over torque switch is adjusted to be larger, accidents such as damaging the deceleration transmission mechanism or valves, or even burning out the motor may occur. To solve this problem, usually during the debugging of the electric control valve, manually shake the electric control valve to the bottom, then shake it one circle in the opening direction, set the lower limit switch position of the electric door, and then open the electric control valve to the fully open position and set the upper limit switch position. This way, the electric control valve will not have the phenomenon of being unable to open manually after being tightly closed, allowing the electric door to open and close freely. However, this inadvertently causes internal leakage of the electric door. Even if the electric control valve is adjusted ideally, due to the relatively fixed action position of the limit switch, the continuous flushing and wear of the valve by the medium controlled by the valve during operation can also cause internal leakage caused by the valve not closing tightly. Solution: Adjust the limit again.
4、Incorrect selection causes cavitation corrosion of the valve, leading to internal leakage of the electric control valve
Cavitation is related to pressure difference. When the actual pressure difference △ P of the valve is greater than the critical pressure difference △ Pc that generates cavitation, cavitation occurs. During the cavitation process, bubbles burst, releasing huge energy and causing significant damage to throttling elements such as valve seats and cores. Generally, valves can operate for up to three months or even shorter under cavitation conditions, causing severe cavitation corrosion and resulting in valve seat leakage of more than 30% of the rated flow rate. This cannot be compensated for. Therefore, electric valves for different purposes have different specific technical requirements, and it is crucial to choose electric control valves reasonably according to the system process flow. Solution: Improve the process by using multi-stage pressure reducing or sleeve regulating valves.
5、Internal leakage caused by erosion of the medium and aging of the electric control valve
After adjusting the electric control valve, after a certain period of operation, due to valve cavitation and medium erosion, wear and tear of the valve core and seat, and aging of internal components, the electric control valve may have a larger stroke and fail to close tightly, resulting in an increase in the leakage of the electric control valve. As time goes by, the internal leakage of the electric control valve will become more and more serious. Solution: Readjust the actuator and perform regular maintenance and calibration.
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DELCO’s quality, competitive prices and excellent service make it the best valve partner to help you grow your business. Customize your valves, we have no minimum order.
At DELCO, we understand the importance of customer satisfaction and strive to meet the unique needs of every client. As a reliable control valve supplier, we are committed to providing excellent customer service and high-quality products to ensure optimal performance and longevity. By choosing DELCO as your trusted control valve supplier, you can benefit from customized valve assemblies designed specifically to meet your requirements, enhancing efficiency and reducing downtime.
Furthermore, our competitive pricing on electronic pressure regulators enables you to offer top-notch solutions. As one of the leading control valve manufacturers, we take pride in delivering reliable valves that not only meet industry standards but also contribute to the overall profitability of your business. By partnering with DELCO, you can have peace of mind knowing that you are making a wise choice for the long-term success of your company.
