Valves often present some troublesome problems in the process of use, such as the valve is not closed tightly, not tight, so what should I do?
Under normal circumstances, if it is not tightly closed, first admit whether the valve is closed in place, if it has been closed in place, there is still leakage and cannot be sealed, then check the condition of the sealing surface. Some valves have removable seals, so take them out for grinding and test again. If it is still not tightly closed, it must be returned to the factory for maintenance or replacement of the valve to avoid affecting the normal use of the valve and presenting problems such as working conditions.
If the valve is not tightly closed, we should first find out where the problem is, and then deal with it according to the corresponding methods.
The reasons for the loose closure of the valve are generally 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 rolled;
(3) The sealing surface of the valve is damaged, resulting in 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 closely touched.
The treatment method of the valve is not tightly closed
1. Impurities are stuck on the sealing surface of the valve
Sometimes the valve is not closed tightly, it may be that there are impurities stuck between the sealing surface of the valve, at this time should not be forcibly closed, the valve should be slightly opened, and then try to close, repeat the try, generally can be eliminated, otherwise it should be checked again. The quality of the medium should also be kept clean.
Second, the stem thread is rusty
In the case of valves, which are normally open, when they are accidentally closed, the stem threads have rusted, and the closure may not be tight. In this case, the valve can be opened and closed several times repeatedly, 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
Regarding the situation that the switch is still not closed tightly after trying to switch many times, that is, the sealing surface has been damaged, perhaps it is corrosion, scratches of particles in the medium, etc., which should be reported for repair.
Fourth, the connection between the stem and the disc is not good
In this case, it is necessary to lubricate the stem and stem nut to ensure that the valve is sensitive to opening and closing. It is necessary to have a formal protection plan to strengthen the protection of valves.
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