GRAPHALLOY®NSF Grade
Replaces Tungsten Carbide Bearings to Achieve Pump NSF Certification

clean drinking water pictureA Design Engineer with a major global pump manufacturer needed bearings to replace the Tungsten Carbide sleeve bearings in their drinking water pumps. According to the engineer: "NSF tested the water from the pump and found Tungsten above the acceptable threshold. I searched the NSF database and saw your Graphalloy material listed. I’d like to set up a virtual call with you to discuss.”

During the virtual meeting, the engineer described the process: “we have to submit our pump to NSF, just the way it would be received by our customer. This means we need to start our testing with the bushing samples, assemble them into our pump, run test the pump, and then send the pump to NSF for testing to be certified.” These drinking water pumps have a maximum temperature of 180°C.

Bearings for drinking water applications

After further discussions with Graphalloy’s engineers, the Design Engineer placed an order for 25 pieces of Graphalloy bronze-grade, NSF 61 certified bushings. Graphalloy engineers custom designed the bushings to be installed into the pump manufacturer’s housings.

A year later, the Design Engineer contacted us and said the initial testing on the Graphalloy bushings had been completed, including endurance testing and NSF tests. According to the engineer: “the results are very promising. No deformation has been observed and we have further testing planned in the next few months. We're also considering design changes to the housing if needed.”

A few months later, the engineer contacted us again to say they considered the Graphalloy bushing tests a success and the pumps have now been sent to NSF for certification.

Graphalloy has two material grades certified to NSF/ANSI 61. NSF certification is the result of Graphite Metallizing’s rigorous product testing to ensure the highest quality GRAPHALLOY® products for the market. Find out more about Graphalloy NSF grades here

Where to use NSF and WRAS Certified Grapahalloy Bushings

  • Municipal Well Pumps
  • Pumps- Potable Water
  • Water Treatment Plant

07-11-2023