What is a chopper pump?
Chopper pumps are a type of centrifugal pump that is used to move solids-laden water through a pumping system. They are similar to grinder pumps in that it includes a mechanism that chops and macerates solids present in the fluid, but it's different in its primary uses. Grinder pumps are typically used in sewage systems to reduce the size of the sewage lines and to pump sewage by pressure to the municipal sewage collection or treatment plant rather than needing to flow there by gravity drain.
Chopper pumps are usually owned and operated by private companies and they are designed for specific industrial or agricultural uses. They are also much larger than grinder pumps and capable of chopping very large solids, such as bones in a meat processing plant, which would not readily pass through a regular centrifugal pump.
How do they work?
The principle behind a chopper pump is relatively simple; the liquid moves into the inlet of the impeller and passes through a rotating chopper mechanism that macerates any solids in the liquid into pieces that are small enough to be handled by the impeller. The chopper teeth are made of hardened materials to chop the solids in the pumped liquid.
Many chopper pump configurations also have a cutter at the back side of the impeller and there may also be a filter at the pump inlet to block any solid pieces that are too large. They are available in a variety of different centrifugal configurations, including horizontal end suction pumps, self priming pumps, vertical sump pumps, and submersible pumps. For the pump types that require the use of mechanical seals, the seal faces must be made of abrasion resistant materials or clean water flush must be provided to the seals to reduce wear on the seal faces.
Where are they used?
Chopper pumps are useful in the treatment of wastewater, but they're more commonly used in industrial and agricultural applications. For example, they're used for pumping manure in large agricultural facilities, and they're also useful for processing waste at fish processing plants, slaughter houses, and meat processing plants.
Vaughan is a leading manufacturer of chopper pumps and centrifugal screw pumps. The company offers a wide variety of chopper pumps to suite nearly every application.
- Submersible chopper pump - the E-Series pump is designed for deep sump applications and allows for max flow to 14,000 gpm and max head to 250 feet.
- End suction chopper pump - available in 3 - 12 inch discharge sizes with max flow rates to 7,000 gpm and total head limits to 280 feet.
- Vertical dry pit chopper pump - the pump is available in both horizontal or pedestal configuration and allows for max flow to 7,000 gpm and heads up to 280 feet. The pump is available in 3 inch though 12 inch discharge sizes.
- Self-priming chopper pump - the PRIME-Cut can prime up to 20 feet and is available in discharges sizes from 4 inch through 10 inch.
- Cantilever chopper pump - built for mining, fish waste, pulp and paper recycling, and storm drains. The cantilever pump is available in 3 inch through 6 inch discharge sizes.
- Vertical wet well centrifugal chopper pump - designed for food processing, mining, chemical, municipal and wood product applications. The pump is available in lengths up to 25 feet and features ductile cast iron casing and bearing housing.
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