The reason and treatment method of the valve is not tightly closed

Under normal circumstances, if it is not tightly closed, first confirm whether the valve is closed in place, if it has been closed in place, there is still a leak can not be sealed, then check the sealing surface. The sealing pair of some valves is removable, so take it out for grinding and testing again. If it is still not tightly closed, it is necessary to return to the factory to repair or replace the valve, so as not to affect the normal use of the valve and the occurrence of working condition accidents and other problems. If the valve is not tightly closed, you should first find out where the problem occurs, and then solve it according to the corresponding method. The valve is not tightly closed for the following reasons: (1) there are impurities stuck in the sealing surface, debris deposited at the bottom of the valve or between the valve disc and the seat; (2) The valve stem thread is rusty, and the valve cannot be turned; (3) the sealing surface of the valve is damaged, resulting in leakage of the medium; (4) The valve stem and valve disc are not well connected, so that the valve disc and the seat can not be tightly contacted. First, there are impurities stuck valve sealing surface valve sometimes suddenly closed loosely, may be the valve sealing surface between the impurities stuck, at this time should not be forced to close, should open the valve slightly larger, and then try to close, try repeatedly, generally can be excluded, otherwise should be checked again. The quality of the medium should also be kept clean. For the valve that is usually in the open state, when it is accidentally closed, because the valve stem thread has been rusted, it will also occur that it is not tightly closed. In this case, the valve can be repeatedly switched on and off several times, while hitting the bottom of the valve body with a small hammer, that is, the valve can be closed tightly, without the need for grinding and repairing the valve.Third, the valve sealing surface is damaged for trying to switch is still not tight, that is, the sealing surface has been damaged, or corrosion, particles in the medium scratch damage the sealing surface, this situation should be reported for repair. In this case, the valve stem and valve disc are not well connected, it is necessary to add lubricating oil to the valve stem and valve stem nut to ensure that the valve switch is flexible. It is necessary to have a regular maintenance program to strengthen the maintenance work of the valve.