With the vast array of trash pumps in the marketplace, choosing the proper unit becomes more a matter of communicating the right information to your dealer rather than knowing all the ins and outs of every pump available. The key? Application details. Go overboard with your pump supplier on explaining where and how you plan to use the pump. Insufficient information may lead your dealer to recommend the wrong size pump, resulting in costly delays. Make sure you provide answers to the following questions before you rent or buy a trash pump:
What do you need to accomplish with the pump?
Is the pump intended for a dedicated function or a variety of tasks?
What type of liquid are you pumping?
Will it include solid matter?
What distance does the liquid need to be pumped?
How quickly does the liquid need to be moved?
Will noise be an issue?
Avoid the temptation to choose the least expensive pump available – unless it’s the pump you truly need. In the long run, paying a little more for the correct unit will save money, especially if your application requires a certain type of pump. For example, if there is a chance you’ll be pumping corrosive liquids, you’ll need a pump with stainless steel parts.
An effective way to select a pump is by looking at the pump’s performance curves. Supplied by the manufacturer, the pump performance curve shows the elevating capabilities of that particular pump at different volumes. Pair the capabilities with your specific application needs to find your pump. The curve relates a wide range of useful information, including the pump’s efficiency percentage and required power input and suction head requirements over a range of flow rates. Pump curves also indicate pump size and type, operating speed, impeller size and best efficiency point (BEP). The pump operates most cost effectively when the operating point is close to the BEP.
Also look for a user-friendly design that offers not only a non-clog impeller, but also an easy-to-access clean-out plate for debris removal. While trash pumps are designed to handle water contaminated with sticks, leaves, stones and other waste materials, any pump can clog and fail if a large enough solid is pulled into the unit. If you’re able to clean debris from the suction side of the impeller, you won’t need to remove the suction line to remove large solids, saving both time and effort. Also, a semi-enclosed impeller can improve the pump’s efficiency.
Selecting a model with heavy-duty features such as replaceable stainless steel wear plates, silicon carbide water seals and high performance mounts for minimized vibration will also extend the life of the pump.
For additional information on using trash pumps safely and productively, see Equipment World’s December 2007 How To Use article.
Keep things running smoothly by following a preventive maintenance checklist such as the one below:
Visually inspect entire unit for leaks or potential problems, including:
Source: Thompson Pump
Recognizing that more contractors are becoming interested in green solutions, manufacturers are now including environmentally friendly design features on their pumps. Thompson Pump, for example, has introduced the Enviroprime system, which addresses sewage, debris and chemical discharge issues. The system prevents blowby from discharging onto the ground by using an air compressor to separate air from water moving through the pump. The continuous separation cycle enables the air to escape separately, eliminating blowby and preventing spillage.
To address noise pollution in sensitive areas, Gorman-Rupp has a priming assisted environmental silent pump, which features an acoustically treated enclosure. The corrosion-resistant aluminum enclosure offers reduced sound levels – as low as 63 dBa under a full load. The priming system eliminates leaks and an oil-lubricated mechanical seal allows the pump to run dry continuously with no damage.
Majid Tavakoli, vice president of applied products, Thompson Pump and Manufacturing
Gary Childress, product planner, Honda Pumps, Honda Power Equipment
Jerry Soto, vice president, Griffin Dewatering Corporation
Tom Aldridge, operations manager, Griffin Pump and Equipment
Jim Widrick, construction pump sales manager, Gorman-Rupp
Marc Leupi, utility product manager, Wacker Neuson
The Hydraulic Institute, www.pumps.org and www.pumpsystemsmatter.org
For a variety of downloadable tools related to pumps, visit www.pumpsystemsmatter.org.