Case Study
pumps," Myracle said. "We were spending 16 hours a month having two field tech- nicians routinely clean and inspect the station because of its condition. But the big- ger costs occurred when the pumps quickly collected rags and other solids that required us to dispatch a crew and truck to pull and re-clean the pump impel- lers an average of twice more a week with additional incidents beyond that after hours that presented over- time charges. Keeping the
This graph further underscores the drop in energy consumption after replacing pumps with N-type units.
station running had become an expensive proposition." Myracle began keeping close track of those costs. The annual man-hour costs at the Rolling Acres Lift Station eventually reached $6,720. Power costs, due to the pump inefficiencies, climbed to more than $937. After adding in the vehicle expense — $960 — the total annual outlay involving the costs associated with the former pumps
reached more than $8,617, he reported. From the prin- cipal line-item costs to keep the lift station running, it was clearly evident the units deserved replacement. Myracle felt the Rolling Acres station was an ideal candidate to install Xylem's Flygt brand N-Pump at the recom- mendation of Gulf States Engineering Co., Inc. The new-generation pumps have earned a reputation for reliability and energy efficiency attributed to
several hydraulic engineering features that prevent clogging and energy-robbing drag resistance imposed when waste materials accumulate on impellers. The pump's semi-open, screw-shaped impeller facilitates the passage of fibrous material associated with solids and the 'disposable' cleaning and personal hygiene wipes being flushed into residential collection lines. Unlike traditional
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