Crane's Fluid Connection Blog | Fluid Handling Tips

A Municipality’s “Classic” Ragging Problem Requires A “Super” Pump Solution

Written by Sara Peters | March 3, 2017

There comes a time when every pump reaches the end of its useable life. For two Classic T Gorman-Rupp pumps at a Fox Crossing lift station, it was after 30 years of reliable service.

As the clearances on the pumps opened between the impeller and the casing, the pumps’ ability to clear rags and debris became more difficult. In turn, air release valves and check valves on the discharge of the pump also struggled with the rags. The check valves, too, were worn, but even after they were replaced in the fall of 2016, struggles with rags continued.

Bill Van Ornum, Lift Station Operator for Fox Crossing, and his team were called out to deal with the ragging issues at the lift station at least every 10 days, spending a couple of hours or more getting the pumps back online. Finally, it was decided to replace the worn pumps with something new.

There are an array of options that can be added to pumps to help alleviate ragging issues. Different brands each have different solutions. For instance, Cornell Pumps touts their chopper and cutter blades to help pass rags. Grinder pumps have also been used in these situations. Each of these options does a great job in their selected applications, but their downfall comes in when it comes to energy efficiency.

Because their Gorman-Rupp pumps lasted so long in the lift station, Van Ornum was determined to replace them with Gorman-Rupp pumps. After speaking with Charlie Isham, a Crane Engineering Sales Engineer, they determined new Super T Series (the newer model of the Classic T) Gorman-Rupp pumps with slightly larger motors (7.5HP instead of 5HP) would keep the lift station running without issue.

But to be even more certain, Isham suggested Fox Crossing take advantage of a new upgrade available for the Super T, the Eradicator Solids Management System.

The Eradicator is a self-cleaning wearplate with a number of notches and grooves, as well as a lacerating tooth that helps break up stringy materials and pass them through the pump without interrupting the pump’s service.

Van Ornum agreed to try the Eradicator upgrade.

After a solid 4 weeks of runtime, Van Ornum reports that he has not needed to tend to the lift station once.

Over the course of 30 years, a lot of new technology and design features change in pumps. Always be on the lookout for those changes, and even upgrades to what you already have to keep lift stations in municipality running without incident.

Having trouble with ragging in your lift station? Ask us about it! We gladly provide technical assistance to municipalities in Wisconsin and upper Michigan.