Regarding the issue of continuous increase in outlet pressure after the diaphragm pump stops
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Both the injection of modifiers and triethylaluminum into the reactor of this device are carried out using diaphragm pumps. For many years, I have been troubled by a problem: even after the pump is stopped and the outlet valve is closed, the outlet pressure continues to rise slowly, sometimes reaching almost the same level as during operation. I’ve asked many people, but no one has been able to give a clear explanation. Has any experienced expert encountered this situation as well? I don’t understand the principle.
This indicates that there may be a leak in your outlet valve. It is recommended to try grinding the valve opening, and also to try reversing the installation direction of the valve. I don’t know what kind of valve you’re using or what the pressure is. To determine whether this approach is feasible, it would be best to send a video.
The discharge of fluid from a reciprocating pump is a process of pulse-like compression; when the pump stops, the pressure within the chamber decreases. If there is internal leakage in the outlet valve, the leaked pressure will be reflected on the outlet pressure gauge. It is recommended to service the outlet valve.
Once the maximum pressure reaches the system pressure and stops rising, there is a problem with the outlet valve.
Amazingly, sometimes it can even be higher than the pressure in the subsequent system!
It’s definitely not an internal leak in the valve; if there were an internal leak, the pressure would keep dropping, after all, the pressure at which the pump operates is higher than the system pressure. Are your outlet valves automatic ones that close automatically when the pump stops? It’s possible that the outlet valve closes too early, resulting in pressure buildup in the pipeline
Are there any other pumps running at this time? For example, if this faulty pump is used as a backup pump and the pressure at that time is similar to that of the operating pump, then it is still due to a leaky outlet valve; since both pumps feed the system through the same pipeline, the outlet pressure remains the same.
I asked today; it might be because the mineral oil pipeline connected to it has electric heating for warming purposes