Choosing the best pump for pumping wastewater, means taking the time and trouble to analyse performance and types of pumps required.  The choices are submersibles, long column sump pumps and more recently, the introduction of Aussie’s bog GMP robust self-priming centrifugal pumps.

Aussie Pumps believe that the big self-priming pump concept works better, not just because of its ease of maintenance but also for its ability to withstand the issues that pumps in applications like this experience.

Corrosion is one consistent problem, particularly for cast iron submersible pumps where a two-year life cycle is often normal.  The pumps also need to be robust enough to handle the job and have that indispensable “self-priming” feature.  Self-priming means that the pump is mounted outside the pit or tank, and draws its water through a suction line connected into the front of the pump.

In a normal installation, the discharge is through an elbow mounted on the top of the pump, but the key feature is the design of the pump body itself. For a self-priming pump, the body will include the capacity for it to hold enough water to prime the pump.  The priming process is simple, virtually foolproof.

“To prime, there are three simple steps,” says Aussie Pumps’ chief engineer, John Hales. “Step one, fill the pump bowl with water through the priming plug mounted in the top of the pump body. Step two, make sure the suction hose or fittings going into the pump body are completely airtight so no danger of air leaks in the suction line.  Step three is to start the motor or engine, depending on the drive system involved.  What happens next is just basic physics. 

“The water in the pump body is expelled to the discharge. That in turn creates a vacuum inside the pump that allows the check valve mounted in the pump suction port to open, allowing water to be sucked into the pump body through the suction hose or pipe assembly.  It’s easy and provides real advantages of convenience,” says Hales.

Aussie’s 2” through to 6” pumps are all designed around a trash or semi trash configuration concept.  The smaller pumps, 2” to 4” are regarded as semi trash, because they have big open non-clog style impellers and feature silicon carbide seals and a stainless steel wear plate.  For extreme applications, 316 stainless steel cast impellers can be provided as an option.

Best of all, semi trash and trash pumps from the Aussie GMP product range all include a front opening port that enables the pump to be cleared out in the event of blockages. 

“Imagine, being able to clean out the pump without having to disconnect pipework, as you do in the case of an end suction pump,” says Hales.  “Ear tags, bones, pieces of hoof, particles of meat or flesh will pass straight through the pump without effort.”

Aussie’s semi trash pump range now includes a 3” pump that not only has the capacity to move over 1,000 litres per minute but, can also deliver heads up to 70 metres.

“That’s a breakthrough product for. It means that the liquid can be pumped further, or higher, depending on the application.”

Experience has shown Aussie Pump engineers that using submersibles in applications like this and long column sump pumps can create real difficulty. 

“We hear about the inconvenience of lifting pumps out of the pit for service. A self-priming pump mounted outside the tank or pond means service can be carried out with a minimum of mess and inconvenience.  It’s the new way, and every day we find more customers moving to our self-priming centrifugal pumps for these difficult wastewater applications,” says Hales.

Aussie is currently looking for distributors in New Zealand for their range of self-priming pumps.  Further information, including a new catalogue on Aussie GMP pumps, is readily available from Australian Pump Industries, visit