Valve in use process often can appear a few problems that make a person perplexed, for example valve close lax, close not tight, how should do that?
In general, if is closed lax, first check to see if the valve is closed in place, if has been closed after putting in place, there is a leak can't seal, then check the situation of the sealing surface, some of the valve seal is removable, grinding it out, test again, if still closed lax, of course, it must be returned to the factory repair or replacement of the valve, so as not to affect the valve working condition of normal use and in accidents and other problems.
If the valve is not closed tightly, you should first find out where the problem occurs, and then solve it according to the corresponding method. The general valve is not closed tightly for the following reasons:
(1) impurities are stuck on the sealing surface, and sundries are deposited at the bottom of the valve or cushion between the disc and the seat;
(2) stem thread rust, valve can not rotate;
(3) the sealing surface of the valve is damaged, resulting in medium leakage;
(4) stem and disc connection is not good, so that the disc and seat deflection can not be in close contact.
The valve is not closed tightly treatment:
One, there are impurities stuck valve sealing surface
Sometimes the valve is suddenly closed loosely, may be between the valve sealing surface impurities stuck, at this time do not apply force to shut down, should open the valve slightly larger, and then try again and again, can be removed, otherwise should be checked, should keep the quality of the medium clean.
Two, stem thread rust
For valves normally in the open state, occasionally closed, due to stem threads have rusted, will also occur loosely closed. To this kind of circumstance, can switch valve a few times repeatedly, at the same time with small hammer knock valve body bottom, can close valve namely strict, need not undertake grinding repair to the valve.
Three, valve sealing surface is damaged
For the case that the switch is still not closed tightly after several attempts, that is, the sealing surface has been damaged and should be reported for repair; Or corrosion, particles in the media scratches and other damage to the sealing surface, should also be reported for repair.
Four, stem and disc connection is not good
Lubricate stem and stem nut frequently to ensure valve flexibility. Have a formal maintenance program.