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Job Stories

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Pump Startup & Shutdown

Pump Startup & Shutdown

Problem: AGI Industries was contacted by a local construction company doing the construction on the West Closure Complex Pump Station in New Orleans, Louisiana. This is one of the largest pumping stations in the United States and is part of the Hurricane Protection Project. During heavy storm conditions, including hurricanes, pumps can inadvertently shut down due to power failure. Pumps will also quickly turn back on when power is restored. When this sudden start/stop of the pump occurs, fluid in the system will change velocity rapidly and can actually reverse direction. New incoming fluid can collide with this reverse flow as the pump restarts. This event causes a severe water hammer effect that can damage piping, valves, and the pumps.

Submarine Bilge

Submarine Bilge

Problem: The Australian Submarine Corp (ASC) uses a 32mm peristaltic hose pump in Collins Class Submarines to transfer oily contaminated seawater from the bilge to the waste tank. The peristaltic hose pump is perfectly suited to the duty because the pump is capable of self-priming, dry running indefinitely, and can handle sludge-type materials that could be encountered in the bilge. The overall physical size of the pump coupled with the cramped internal confines of the submarine resulted in the suction and discharge pipe work being considerably twisted; incorporating many bends and valves. The pulsed flow action caused the acceleration head of the pump to sharply increase and markedly decrease hose life to the extent that offshore trials were lasting less than a week.

Sump Storm Water

Sump Storm Water

Problem: The Park Royal Hotel in Sydney has two large Flygt submersible pumps which operate automatically to pump out storm water and seepage. The pumps are installed in a sump in the basement car park. When the pumps shut down due to low level in the sump, the backflow of the storm water still in the discharge line returned against the check valve at the pump's discharge. This caused severe pipe vibration and water hammer. The force was so great that the pipe, mounted on the basement ceiling with brackets and Ramset dyna-bolts, was dislodged, landing on expensive motor vehicles.

Water Supply

Water Supply

Problem: A major producer of water treatment chemicals accessed their local water supply through a 3" PVC pipe with quick closing valves. When the desired quantity had been measured and the valve shut, a water hammer effect with pressure spikes that exceeded the PVC pipe's burst strength was created. The PVC repeatedly broke, causing the entire plant to be shut down for repair. In addition, since pipe failure occurred under a nearby highway, it also had to be closed.

Waste Water

Waste Water

Problem: Vishay Measurements Group uses a Wilden 1" Air Operated Double Diaphragm pump to pull the plants processed waste water out of a pit and pump it over to the waste water plant to be processed. The reciprocating action of the pump caused pulsation in the PVC discharge pipe which caused the system to vibrate. The continuous shaking of the PVC pipe caused joints to break apart and stress caused cracking in the discharge pipe.

View All Dosing Filling Water Hammer Spill Prevention Filter Metering Injecting Pulsation Dampening Spray Coating Transfer Inlet Stabilization
JOB STORIES