How to stabilize the outlet pressure and flow rate of a stainless steel pneumatic diaphragm pump

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How to maintain stable outlet pressure and flow rate in stainless steel pneumatic diaphragm pumps: http://www.b-fz.com/UploadFiles/QBY%E5%9E%8B%E4%B8%8D%E9%94%88%E9%92%A2%E6%B0%94%E5%8A%A8%E9%9A%94%E8%86%9C%E6%B3%B5(1).JPG To ensure stable pressure and flow rate while the stainless steel pneumatic diaphragm pump is in operation, buffer tanks are installed on both the inlet and outlet pipes of the pump. The buffer tank must be pre-charged with nitrogen to a certain pressure; this pre-charging pressure should, in principle, not be lower than 30% of the maximum operating pressure nor higher than 80% of the minimum operating pressure. Although a higher priming pressure can provide better cushioning, a decrease in pressure leads to pulsations that frequently strike the bottom of the tank, causing damage to the metal components inside. When the operating pressure range is wide, it is sufficient to pre-charge the system to 30%–35% of the maximum operating pressure. The pre-charge pressures specified by water pump manufacturers are as follows: the pre-charge pressure for the inlet buffer tank should be 80%–90% of the inlet pressure, while the pre-charge pressure for the outlet buffer tank should be 60%–65% of the outlet pressure. During the actual operation of the diaphragm pump, significant vibration in the pump’s inlet pipe indicated that the pre-charge pressure of the inlet buffer tank was not appropriate. By adjusting this pre-charge pressure to 60%–65% of the inlet pressure, according to the actual conditions, the vibration was immediately eliminated and the pump returned to normal operation. During operation, the pressure in the buffer tank of a stainless steel pneumatic diaphragm pump gradually decreases due to leaks and other factors. When this pressure reaches a certain level, the pump operates unevenly and produces abnormal noises. When it operates for extended periods at low pressures, the diaphragm experiences large fluctuations, which can lead to fatigue in the diaphragm and reduce its service life. To overcome this situation, it is necessary to pump air into the buffer tank during operation. Based on the experience gained during the commissioning of stainless steel pneumatic diaphragm pumps as well as during normal operation, it was decided to inject pressure into the buffer tank while the pump was in operation; the stability of the pressure gauge needle served as an indicator that the pressurization had been successful. Several tests yielded excellent results, ensuring the long-term safe operation of the stainless steel pneumatic diaphragm pumps.