Managing difficult solids requires more than simply providing a larger passage through the pump
Selecting a wastewater pump for solids-heavy applications involves more than checking the diameter of its solids passage. The type, shape and behavior of the material entering the pump—and how that material interacts with the impeller and suction area—can have a significant effect on reliability.
Fibrous materials present a particular challenge. Wipes, rope, plastic bags, cloth and similar materials may bend, wrap or accumulate rather than simply pass through a pump. One critical area is the low-pressure region near the center of the impeller, where material can collect and contribute to clogging.
Pump design can help address the problem before a blockage develops. Tsurumi's newly introduced BN Series Submersible Smashing Cutter Pump uses a semi-open channel impeller with an extended rotating guide working together with a heart-shaped stationary suction blade. The guide directs incoming material toward the cutting area, where rotating and stationary components crush, cut and shred solids and long fibrous materials.
Effective solids handling also has to be balanced with hydraulic performance. A pump designed to resist clogging still needs to deliver the required flow and head efficiently. The BN Series combines its smashing cutter mechanism with a semi-open channel impeller designed to maintain hydraulic performance while handling difficult solids. In some applications, this can also allow comparable performance at lower installed horsepower than Tsurumi's previous C Series cutter pumps.
The relationship between critical pump components is also important. In conventional wastewater and industrial pumps, maintaining the specified clearance between the impeller and suction cover helps prevent underperformance and overcurrent. In the BN's smashing cutter mechanism, a narrow, inclined clearance between the rotating leading blade and heart-shaped stationary suction blade supports effective cutting action. The impeller and suction cover are constructed of ductile cast iron selected for impact resistance, helping the cutting components withstand repeated contact with difficult material.
Ultimately, effective solids handling requires looking beyond a single specification. The characteristics of the solids, how they enter and move through the pump, impeller and suction design, hydraulic requirements, and critical component clearances all influence how effectively a pump can handle challenging material. Considering these factors together can help operators select equipment for more reliable operation.
For more information about the BN Series Submersible Smashing Cutter Pump, visit www.tsurumipump.com/bn-series, email [email protected], or call 888-878-7864.
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