In general, if it is not tightly closed, first confirm to see if the valve is closed in place, if it has been closed in place, there is still leakage can not be sealed, then check the sealing surface, some valves are detachable, then take them out for grinding, test again, of course, if it is not closed strictly, then it must be returned to the factory for maintenance or replacement of the valve, so as not to affect the normal use of the valve and problems such as working condition accidents.

Generally, the reasons for the loose closure of the valve are as follows:

(1) There are impurities stuck on the sealing surface, and the debris is deposited at the bottom of the valve or between the valve disc and the valve seat;

(2) The stem thread is rusty, and the valve cannot be rotated;

(3) The sealing surface of the valve is damaged, resulting in the leakage of the medium;

(4) The connection between the valve stem and the valve disc is not good, so that the valve disc and the valve seat are deviated and cannot be in close contact.

The treatment method of the valve is not tightly closed:

1. Impurities are stuck on the sealing surface of the valve

The valve is sometimes closed suddenly, it may be that there are impurities stuck between the sealing surface of the valve, at this time it should not be forcibly closed, the valve should be opened slightly larger, and then try to close, try repeatedly, it can generally be eliminated, otherwise it should be inspected, and the quality of the medium should be kept clean.

Second, the stem thread is rusty

For valves that are normally open, when they are closed occasionally, they may not close tightly because the stem threads have rusted. In this case, the valve can be opened and closed several times, and the bottom of the valve body can be tapped with a small hammer at the same time, which can close the valve tightly, and there is no need to grind and repair the valve.

3. The sealing surface of the valve is destroyed

For the situation that the switch is still not closed tightly after trying to switch many times, that is, the sealing surface has been damaged and should be repaired; Or corrosion, particle scratches in the medium, etc., damage the sealing surface, should also be repaired.

Fourth, the valve stem and the valve disc are not well connected

Lubricate the stem and stem nut frequently to ensure that the valve switch is flexible, and a set of formal maintenance plans should be required.