Diaphragm pump does not deliver flow

:) Try to analyze the reasons why metering pumps and diaphragm pumps do not deliver fluid, as well as the corresponding solutions, from the following aspects: Cause of the fault Solution 1. The valves on the suction and discharge pipes are slightly closed or blocked, or the filter is clogged 1. Open the valves, and inspect the suction pipes, discharge pipes, and filter 2. The valve contact surfaces are damaged or there are debris on them, preventing proper sealing 2. Check the tightness of the valves; replace the valve seats if necessary 3. Leakage in the piston packing 3. Replace the packing or tighten the packing gland 4. The pump’s stroke length is too short 4. Increase the stroke length appropriately 5. The diaphragm is ruptured or damaged 5. Replace the diaphragm 6. Air is present in the suction or discharge pipes 6. Open the drain valves at the suction or discharge pipes to remove air and liquid:loveliness:

The second floor covered it quite comprehensively, but one more thing to add: for hydraulic diaphragm pumps, if the liquid level in the tank is too low, the pump will also be unable to deliver a sufficient volume of fluid.

There are many reasons why a diaphragm pump does not deliver the desired flow rate. It should be clear first that the metering pump is only one part of the entire metering system; there are two main factors that can cause a lack of flow: the pump or the system, and in most cases it is the latter – issues related to the system – that are to blame. Therefore, when the flow rate is low, the first thing to check is whether your system is functioning properly – whether there are any blockages or leaks in the inlet and outlet pipes, whether the filters are clogged, and whether the inlet check valve and the outlet check valve are blocked or stuck. Also, check whether there is any air in the outlet pipeline! Is the hydraulic oil system functioning properly? Generally, the above factors are ruled out first, and then the cause inside the pump is investigated – could it be a ruptured diaphragm? Is it due to insufficient refilling of hydraulic oil? Or has the built-in pressure relief valve been activated?

Check whether the suction side and the exhaust line are unobstructed. Check whether the air circuit meets the requirements, inspect the directional valve, and check if there is severe internal leakage in the check valve – this is very important. The key issue is internal leakage in the check valve; in such cases, the pump will seem to operate more gently with less power consumption.

What was said upstairs is very detailed; if no charge is applied, a diaphragm rupture pump will experience leakage!

Another point to consider is whether the inlet flow rate is normal; insufficient back pressure at the inlet can also lead to a low flow rate, preventing the pump from delivering sufficient volume.

I agree with the opinion from the second floor; the main problems I encounter are air leakage or excessive water accumulation

Add a new point: An air supply pressure that exceeds the normal operating pressure can also affect the flow rate of the diaphragm pump.

Reply to 7# Close contact: If the diaphragm only has slight leakage and the pressure at the pump outlet isn’t very high, the flow rate might remain okay; but if the leakage is severe, the flow rate will definitely not be high.