The 10 common causes of failure of pneumatic diaphragm pumps and their solutions are as follows:
Diaphragm damage or aging
The diaphragm ruptures due to long-term use or medium corrosion, and the diaphragm needs to be replaced in time. If liquid leakage or abnormal noise is found in the pump body during inspection, it is usually related to diaphragm failure.
Abnormal air source pressure
Insufficient or too high intake pressure will cause the pump to fail to start or the flow rate to drop. It is necessary to ensure that the air source pressure is stable and the pressure difference (intake and discharge pressure) is at least 0.7 bar.
Leakage or blockage of inlet and discharge valves
The valve ball or valve seat fails to seal due to wear, foreign matter blocking or material mismatch, and the valve ball needs to be cleaned or replaced.
Worn or loose seals
Aging or improper installation of pump body gaskets, O-rings, etc. causes leakage and gas leakage, and the seals need to be adjusted or replaced.
Lubrication problem
Excessive, insufficient or wrong type of lubricant can cause piston jamming. Low-viscosity lubricants that meet the requirements should be used, and the lubrication system should be checked regularly.
Pipeline or suction port blocked
Foreign matter or medium crystallization blocks the pipeline, and the filter needs to be cleaned and checked. If high-viscosity liquid is transported, the pump speed needs to be reduced to avoid cavitation.
Cavitation phenomenon
High vacuum at the suction port or insufficient liquid vapor pressure causes cavitation, which is manifested as a sudden drop in flow and cavitation spots on the pump body. The suction stroke needs to be optimized and the pump speed needs to be reduced.
Foreign matter blocks the inside of the pump body
Impurities in the pump cavity or air valve channel will hinder the movement of components, and the filter device needs to be disassembled for cleaning and inspection.
Pneumatic valve failure
Poor contact of the control line, wear of internal parts or abnormal air pressure will cause start-stop failure. The air valve needs to be repaired and damaged parts replaced.
Improper installation of the diaphragm
The diaphragm pressure plate is installed in reverse or not locked, which will cause jamming or leakage during operation. It needs to be reinstalled according to specifications and the tightness of the clamp needs to be checked.