What to do if the electric regulating valve is not closed tightly

How to deal with the "regularly closed" electric control valve?
The birth of electric control valves has made a huge impact on the control valve industry, and has quickly become a mainstream product. During the growth process, it has also received suggestions from people from all walks of life and valve manufacturers. The control valve has a simple structure, and it is easy to operate and maintain. Convenient features. During the use of the valve, there are often some disturbing problems, such as the problem of inadequate closing. Let's take a look:
First, the zero setting of the actuator is not accurate, and the valve's fully closed position has not been reached.
  Adjustment:
1. Close the valve manually (must confirm that it is completely closed);
2. Manually close the valve with force, subject to slightly tightening with force;
3. Screw back (open valve direction) half a turn;
4. Then adjust the limit.
2. The valve is a downward push-closed type. The thrust of the actuator is not large enough. When there is no pressure, it is easy to adjust to the fully closed position. When there is a downward thrust, the upward thrust of the liquid cannot be overcome, so it cannot be closed.
Solution: Replace the actuator with large thrust or change to balanced spool to reduce the unbalanced force of the medium.
Third, the internal leakage caused by the manufacturing quality of electric control valves, valve manufacturers in the production process of the valve material, processing technology, assembly technology and other controls are not strict, resulting in unqualified sealing surface grinding, defective products such as pitting, trachoma, etc Elimination, resulting in end leakage.
The solution can reprocess the sealing surface.
4. The control part of the electric control valve affects the internal leakage of the valve. The traditional control method of the electric control valve is through mechanical control methods such as valve limit switches and over-torque switches. Because these control elements are affected by the ambient temperature, pressure and humidity, Caused by objective factors such as valve misalignment, spring fatigue, uneven thermal expansion coefficient, etc., causing internal leakage of electric control valves.
The solution can readjust the limit.