Globe valve operation

- Feb 25, 2019-

For the shut-off valve, not only will it be installed and maintained, but it will also operate.


To open and close the shut-off valve, the force should be stable and not impact. Some components of high-pressure shut-off valves that have been opened and closed have been considered such that the impact force is not equivalent to a general shut-off valve.


When the shut-off valve is fully open, the handwheel should be reversed a little to make the threads tightly tight to avoid loose damage.


When the pipeline is used initially, there is a lot of internal dirt. The shut-off valve can be slightly opened, and the high-speed flow of the medium is used to wash it away, and then it is gently closed (cannot be closed quickly and violently closed to prevent residual impurities from pinching the sealing surface) , turn it on again, repeat this many times, flush the dirt, and put it into normal work.


Normally open the shut-off valve, there may be dirt on the sealing surface. When it is closed, it should be washed clean by the above method, and then officially closed.


If the handwheel or handle is damaged or lost, it should be immediately equipped. It should not be replaced by a live wrench, so as to avoid damage to the valve stem, and the opening and closing is not working, resulting in an accident in production.


Some media, after the shut-off valve is closed, cool, so that the valve member shrinks, the operator should close again at the appropriate time, so that the sealing surface does not leave a slit, otherwise, the medium flows through the slit at a high speed, and it is easy to erode the seal. surface.


When operating, if you find that the operation is too laborious, you should analyze the cause. If the packing is too tight, it can be loosened properly. If the valve stem is skewed, the person should be notified to repair it. In some closed valves, the closing member is heated and expanded, which makes opening difficult; if it must be opened at this time, the bonnet thread can be loosened by half a turn to one turn, the stem stress is eliminated, and then the hand wheel is driven.