How to operate the shut-off valve? Pneumatic pinch valve experts introduce you

For shut-off valves , not only must be able to install and maintain, but also must be able to operate.

When opening and closing the shut-off valve, the force should be steady without impact. Some parts of the high-pressure cut-off valve that are opened and closed have been considered that this impact force cannot be equal to the general cut-off valve.

When the shut-off valve is fully opened, the handwheel should be turned upside down to make the threads tightly to avoid loosening and damage.

When the pipeline is first used, there are a lot of internal dirt. You can open the shut-off valve slightly, use the high-speed flow of the medium to wash it away, and then close it gently (not fast or violently to prevent residual impurities from trapping the sealing surface) , Turn it on again, repeat this many times, flush out the dirt, and then put it into normal work.

Normally open shut-off valve, there may be dirt on the sealing surface. When it is closed, use the above-mentioned method to flush it, and then formally close it tightly.

If the hand wheel and handle are damaged or lost, they should be equipped immediately, and can not be replaced with a flexible wrench, so as to avoid damage to the valve stem and failure of opening and closing, resulting in accidents in production.

Some media cool down after the shut-off valve is closed, which will cause the valve to shrink. The operator should close it again at an appropriate time so that the sealing surface does not leave any crevices. Otherwise, the medium will flow through the crevices at high speed, which will easily erode the seal. surface.

During operation, if the operation is found to be too laborious, the reason should be analyzed. If the packing is too tight, it can be properly loosened. If the valve stem is skewed, the personnel should be notified to repair it. In some shut-off valves, when the closing part is closed, the closing part is heated and expands, which makes it difficult to open; if you need to open at this time, you can loosen the bonnet thread by half a turn to one turn to cancel the valve stem stress, and then move the handwheel.

When the shut-off valve starts to close from the fully open position, as the valve flap drops, the fluid creates a pressure difference before and after the valve flap to prevent the valve flap from falling, and this resistance increases rapidly as the valve flap drops. When the shut-off valve is fully closed, the pressure difference between the front and rear of the disc is equal to the working pressure of the medium, and the resistance is large at this time. With the forced sealing force, the operating force at the moment of closing the shut-off valve increases quickly.