GRAPHALLOY NSF® Certified Bushings Succeed in Desalination Plant's Pumps

A major pump manufacturer’s water systems group, which focuses on the commercial and industrial water markets, won a contract to provide vertical turbine pumps for a desalination facility at a publicly-owned water agency in California.

The pumps would experience dry starts with the possibility of prolonged dry running. In addition, the bushings needed to be NSF certified bushings. These conditions led the pump company to replace their standard bronze bushings with GRAPHALLOY NSF certified bushings. The unique properties of GRAPHALLOY bushings and wear rings enable pumps to run dry and survive upsets and flashing that cause metal wear parts to fail.

Graphalloy is self-lubricating, non-galling and works in a wide temperature range, from -450°F to +1000°F.  Graphalloy is a softer material that will not damage the shaft. These qualities make it a good match for severe service pumps, as it can survive frequent flashing and run dry episodes better than metal or plastic wear parts while protecting the rotating parts.

Graphalloy bushing in housingGraphalloy for water applications

GRAPHALLOY bushings were installed as bowl bushings for multiple deep-well vertical turbine pumps, pumping brackish water. The water properties are:

  • Brackish Raw Water
  • Total dissolved solids: 1,125 to 3,000 mg/L
  • Normal Temperature: 78° F (25°C)
  • Specific Gravity: 1.0
  • Viscosity: 1.1 CP
  • Vapor Pressure: 0.36 psi
  • PH: 7 to 8.5

GRAPHALLOY GM 695.3, an NSF certified Babbitt grade, was used for this application. GRAPHALLOY NSF materials are certified for use in municipal well pumps and water treatment plant applications.

The pumps were installed at the desalination plant in February 2017 and have been running with no issues.

For more information on GRAPHALLOY bushings and wear rings, including our NSF certified grades, please click here to contact us