AFMC Command News

Arnold AFB pumping station receives crucial investment

  • Published
  • By Jill Pickett
  • AEDC Public Affairs

The Arnold Engineering Development Complex (AEDC) Civil Engineering Branch at Arnold Air Force Base, Tenn., recently completed a project to restore reliability through redundant systems and smooth the way for future maintenance.

In 2017, routine maintenance of a 60-plus-year-old pump at the Primary Pumping Station revealed a failure in the casing of one of the pumps. Similar to resurfacing brake rotors on a vehicle, the impeller casing on the pump can be refinished to extend the life of the pump, but only as long as enough material remains. In this case, the pump had been refinished numerous times to the point that after the additional wear and tear since the last refinishing, there was not enough material left to support loads during operations, leading to failure of the pump.

The pump was one of the originals installed in 1953 when the pumping station was constructed. The station pumps water from Woods Reservoir to support the aerospace ground testing facilities used to prove the superiority of systems required to meet the demands of the National Defense Strategy. Multiple pumps provide water to Arnold AFB to meet capacity needs - up to 104,500 gallons per minute if necessary - and provide redundancy when maintenance is necessary.

Due to the size of the equipment, previous maintenance was performed on the pump-and-motor sets using an overhead crane within the building to disassemble the equipment into pieces.

“Arnold AFB Civil Engineering Branch designed a system to speed pump replacement time and improve maintenance efficiency by adding roof access hatches to the 35-foot-tall building,” said Abigail Huyler, a program manager in the Engineering Section of the Civil Engineering Branch.

Hatches were designed to allow the pumps to be removed intact through the roof using a mobile crane, significantly reducing the amount of time required to remove the pumps needing service and install replacement pumps.

After design and planning, work began on the project in August 2020 and was completed in February 2022 with successful commissioning of the pump. The major mechanical components of the new pump are expected to last as long as the original.

The project was not without its challenges. As with many projects at Arnold AFB, the team had to join old and new technology.

“One of the biggest challenges of the project, was finding a way to make current technology interface with the 1950s-era equipment,” said Joshua Cooke, an Air Force senior utility manager at Arnold Air Force Base. “We couldn’t just go in and start tearing out things and changing configurations, because the older pumps still relied on those older components.”

Upgrades are planned for some of those components, such as the electrical switchgear. Additional work is also planned on the control system and adding roof hatches to access the other pump-and-motor sets.

The other pumps will eventually need to be replaced as well, adding further importance to this project.

“The project was unique in that we were tasked with delivering the template by which all future pumps will conform,” Cooke said. “We needed to get it right, because every remaining pump, when replaced, will be nearly identical to this pump.”

This effort was made a little easier by some good fortune. The pump bowl assembly is cast in multiple pieces from ductile iron, which requires a mold. The team found the original mold data from 1953 and converted it into a map that could be used with current mold-making technology. Having this map will also reduce cost and production times for future pump builds.

“My hat goes off to the entire team,” Cooke said. “The project was only a success because the Air Force was provided support from the most knowledgeable and experienced people in the business. Every person involved, including individuals from the TOS [Test Operations and Sustainment] contractor and the FARM [Facilities Acquisitions for Restoration and Modernization] contractor, were crucial to the project.”