Air Diaphragm Pump Troubleshooting

Air operated diaphragm pump is a new type of conveying machinery, and it is the most novel type of pump at present. Using compressed air as the power source, it can absorb all kinds of corrosive liquids, liquids with particles, high viscosity, volatile, flammable and highly toxic liquids. However, many customers have some problems in the process of using the AODD pump. Then, we will troubleshoot the air diaphragm pump next.

Air operated diaphragm pump does not start.

Check whether the filter, pressure regulating and lubricating device and the filter screen of the air inlet are blocked or damaged by debris.
Check whether the air valve is stuck by impurities, then disassemble the air valve and clean it thoroughly, and check whether the piston oil in the air valve has scratches. If the surface of the piston is bright instead of pure black, it means that the piston has been damaged. We suggest that you should replace the piston and O-ring in time.
Check the spindle for scratches, abrasions and flattening marks. If damaged, replace it in time.

Air operated diaphragm pump leaks.

Check packing sealing, if there is water leakage, increase or replace asbestos rope packing.
The coupling bolts and rubber pads of the coupling should be replaced if damaged.
Tighten the base screws and do anti-rust treatment.
Due to the frequent operation of the air diaphragm pump, the bearings at both ends of the coupling should be disassembled for cleaning or replacement every year.
The appearance inspection should be clean, the nameplate is intact, and the grounding wire is well connected.
The phase wires and connecting pieces in the motor junction box should be firm and tight.
The switch of each valve should be flexible and reliable, and there should be no leakage inside and outside.
The one-way valve should be flexible in action, and there should be no water leakage inside or outside the valve body.

Pneumatic diaphragm pump does not work after venting.

The valve core is seriously worn and stuck.
The shaft sleeve of the central shaft is worn, and the copper sleeve should be replaced at this time.
The screws at both ends of the central axis fall off.
The two diaphragms in the pump are broken.
The diaphragm pump is placed upside down or flat, and the valve core cannot be returned.

Diaphragm pump muffler leaks.

The O-ring of the valve core is worn, please purchase the air spare parts package.
The valve core is worn, replace the valve core and valve sleeve.
The sealing ring on the intermediate shaft is damaged, replace the sealing ring.

Diaphragm pump muffler leaks.

The diaphragm is broken (especially if there are large particles in the conveyed material).
The diaphragm platen is loose or broken.
The water content in the compressed air is too high or the oil content is too high.

Air operated double diaphragm pump cannot pump liquid.

The specific gravity of the liquid is too large, or the concentration is too large, and the suction stroke of the pump cannot be reached.
The valve ball and ball seat in the pump body of the pneumatic diaphragm pump are not well sealed, and the pumped liquid flows back immediately. In this case, the pump body is liquid, but the flow rate is very small and the lift is very low.
The sealing of the liquid inlet pipe is not good. Although the pump is working normally, it cannot absorb the liquid.
The air source pressure of the air inlet is not enough. The air source pressure range of the pneumatic diaphragm pump is generally 2-7kg, and the pump cannot work normally if it is larger or smaller than this value.
The wearing parts in the pump body of the pneumatic diaphragm pump are worn out, just replace the wearing parts.
The inlet and outlet of the pump are reversed. The inlet of the pump is at the bottom and the outlet is at the top.

Diaphragm pump can not pump material.

The ball valve is worn or the ball seat is not well sealed, and the accessories need to be replaced.
Check the feeding pipe for air leakage. If air enters the feeding port, it will not suck the material.
If the viscosity of the conveyed liquid is too large, it will also lead to the situation that the material cannot be sucked, because the excessive viscosity of the liquid will drive the movement of the one-way valve, resulting in the failure of the one-way valve.

Diaphragm pump exhaust is frozen.

Check whether the water content in the compressed air is too high, and install air drying equipment according to the situation.
Check whether the diaphragm is broken, check whether the clamp is locked, especially the inlet pipe clamp.
Air should flow out from the discharge port.
Check whether the diaphragm is broken, check whether the diaphragm and the inner and outer splints are clamped on the shaft.
If the pneumatic pump has abnormal noise, the user can choose to increase the outlet or inlet head.

Insufficient pressure in the AODD pump.

Low or no pressure. Consider that the operating ambient temperature is too low. When running at low temperature, the oil return pipe of the diaphragm pump may also freeze, which will affect the automatic oil replenishment of the hydraulic system, resulting in insufficient pressure in the cavity and a drop in the pressure of the diaphragm chamber. In view of this situation, the old oil can be drained and replaced with reliable anti-freezing and anti-wear hydraulic oil.
The outlet pressure is uneven. The outlet pressure is uneven and fluctuates greatly. It is necessary to carry out routine inspection of the pressure gauge and clean the raw material outlet valve group. If there is still a problem, it is necessary to further clean the filter at the inlet, check the gas regulator, and adjust the pressure to be consistent with the working pressure. If it is damaged, please replace it with a new one in time.
Pressure reduction. If the outlet pressure suddenly drops abnormally during operation, you can check whether the hydraulic oil level decreases accordingly. If there is oil replenishment in time, if there is still a problem, you can check the oil replenishment valve, the raw material inlet and outlet valve groups, and the external seal of the pump body. Damaged can be replaced with a new one. Check the piston rubber in turn and whether the diaphragm is severely worn or aged.

How to drain water from an air diaphragm pump?

Install a valve at the inlet of the air operated diaphragm pump. When you stop using the pneumatic diaphragm pump, first close the valve, and then open the pump for a few minutes to drain the medium in the diaphragm pump body, so as to avoid difficulty in opening the pump next time. Or put the inlet and outlet of the diaphragm pump down, which can basically empty the water. When repairing and replacing the diaphragm, it is necessary to clean the connecting rod and copper sleeve in the pump body of the diaphragm pump, and do not damage the sealing ring.