- Main causes of internal leakage of valves
1. Wear of sealing surface: the sealing surface of the valve will wear out in long time use, especially in high temperature, high pressure, high speed fluid conditions are more prominent. Wear of the sealing surface will lead to the valve can not be completely closed, resulting in internal leakage.
2. sealing packing loose or aging: valve packing is to ensure the key part of the seal, if the packing is loose or aging, will lead to the valve spool can not be tightly affixed to the valve seat, resulting in internal leakage.
3. spool and seat mismatch: spool and seat with the precision of the valve directly affect the sealing performance of the valve. If the spool and seat mismatch, will lead to good sealing effect can not be achieved, resulting in internal leakage.
4. loose spring or failure: the spring in the valve plays the role of sealing surface close to the role of the spring, if the spring is loose or failure, can not ensure the sealing performance of the valve, resulting in internal leakage.
- Solutions
1. Replace the sealing surface and packing: Check and replace the sealing surface and packing of the valve regularly to ensure that they are within the normal working range and to avoid internal leakage due to wear or aging.
2. Adjust the clearance between the valve spool and the valve seat: by adjusting the fit clearance between the valve spool and the valve seat, ensure that the sealing performance of the valve reaches the best state and reduce the occurrence of internal leakage.
3. Repair or replace the spring: check whether the spring in the valve is loose or invalid, repair or replace it in time to ensure that the valve can be closed properly and tightly to avoid the occurrence of internal leakage.
4. regular maintenance and overhaul: regular maintenance and overhaul of the valve, clean the impurities and dirt inside the valve to ensure the normal operation and sealing performance of the valve.
5. Selection of suitable valves: in the design and selection of valves, should be based on specific working conditions and media characteristics, select the appropriate type of valve and material to improve the wear resistance and sealing performance of the valve.