First, we can listen to the sound. This refers to listening to the sound of the medium flowing. Because we can't directly see the situation in the pipeline, we can close the valve first, and then open it slowly, listening to the sound of the medium flowing during this process. If you can hear the valve opening normally, then eliminate the guess that the valve disc is falling off. If you don't hear it, it means that the valve has not opened, and consider that the valve core may fall off.
Secondly, consider the starting torque. Because the movement direction of the gate valve disc is just perpendicular to the medium, the starting torque should be relatively large. If you feel very relaxed when opening the valve, the valve stem can easily turn in a circle or the handwheel is very light, the opening and closing are obviously easier than usual, you can feel effortless and can rotate quickly, and you can feel that the valve stem is not hanging on anything, then Most likely the valve disc has come off.
Then we can also judge by observing the changes in flow and pressure. If the valve disc has fallen off, such as the rising stem gate valve, it must be that the valve stem has come up when the valve is opened, but there is no flow, and the pressure gauge and flow meter display no change. When the valve is closed, the screw does not return to the end, and it cannot be closed again, because the valve disc has blocked the valve stem. As long as the switch is repeated several times to see if it can be closed to the end, it can also be judged. Generally, there will be traces on the valve stem.
Of course, the failure of flow regulation is not entirely due to the valve disc falling off, and sometimes because the radial direction of the valve disc is stuck. When we use the handwheel to drive and adjust it, there is no medium flowing out and no flow change occurs. In fact, the valve disc is blocked in the radial direction when it is fully opened or moving. In this case, we only need to remove the internal dirt.
However, according to the feedback of many on-site cases, in addition to ball valves, other types of valves such as gate valves, butterfly valves, check valves, etc. rarely have the phenomenon of valve disc falling. Although this does happen, the probability is very small. The situation is very bad. Therefore, when purchasing, we must carefully choose the manufacturer, and we must choose the brand manufacturer with integrity and reputation in order to obtain the greatest guarantee on the quality of the gate valve. For more information on gate valves, please contact Bundor Valve online customer service for details.
