Testing Your Air Operated Diaphragm Pump
HOW DO YOU TEST AN AIR OPERATED DOUBLE DIAPHRAGM PUMP AFTER MAINTAINING IT?
If you have carried out maintenance on an AODD Pump it’s always best to ensure it is working correctly before putting it back into your process.
SAFETY FIRST
- Check that original manufacturers spare parts have been used – non-original parts can be dangerous and will invalidate any warranty or certification issued on the pump.
- Check all connections are tight and have been correctly torqued as per manufacturer’s instructions
TO TEST
Connect a suitable airline to the pump - Min 10mm on pumps with 7" or 10" Diaphragms or 20mm on pumps with 12" or 14" Diaphragms.
DRY LIFT
- Connect a vacuum gauge to the pump inlet – turn the air on to the pump – check the vacuum reading is as per the dry lift on the manufacturer’s literature.
- Turn off the air to stop the pump.
PUMP OPERATION
- Connect the pump via suitable pipework to a liquid source (Clean Water) and connect up an outlet to the pump either taking the liquid to recirculating tank or to drain where applicable.
- Ensure you have a valve in the outlet pipework.
- Start the pump slowly to prime and build up speed until the pump is running as the speed required on the application.
- Pump should be cycling evenly, pumping the liquid.
PUMP INTEGRITY
- While operating the pump at its maximum flow / pressure; slowly close the valve in the outlet pipework until the pump ‘Dead Heads’ and stops running. This is when the liquid pressure in the outlet pipework reaches the same pressure as the air pressure being given to the pump.
- No harm is done to the pump – AODD Pumps are designed to be able to ‘Dead Head’
- Inspect the pump, paying special attention to the body / manifold seals as well as the Diaphragm seals, for leaks.
- Once the inspection is complete slowly open the valve in the delivery pipework, the pump will start cycling again once the pressure in the delivery pipework drops.
- Turn off the air to stop the pump.
DRAINING THE PUMP
- Pump can be run without connection to the liquid source, this will pump most of the liquid out of the pump.
- Further liquid can be drained out by tipping the pump where applicable and safe to do so.
- Warm air can be passed through the pump if required to fully dry the pump.