When bearing manufacturer Daido Metal Co wanted to replace the white metal in its large high-load and high-speed revolution bearings for hydro-generator applications, it chose Victrex® PEEK because of its excellent durability and sliding properties. Applying PEEK, a high performance polyaryletherketone, to the surface of the bearings enabled Daido, located in Nagoya, Japan, to improve the load-bearing capacity by 50% and reduce friction by approximately 30-40%.

"This enabled the surface of the bearing to be reduced by approximately 60% and the operating temperature to be increased to 250°C (482°F) compared to 125°C (257°F) for white metal products," explains Andrew Ragan, Victrex Global Leader-Industrial. "Daido's testing indicates that bearing life will potentially increase to twice that of white metal-based bearings."

A proprietary impregnation technique is used to apply PEEK to the surface of the bearings. Explains Ragan, "Ultra-fine bronze beading is sintered on the back of the rear steel plate surface, and then the resulting porous intermediary layer of Victrex PEEK is injected, using a proprietary technique. In this way, the base material (steel) and the sliding surface (PEEK) are completely joined together."

PEEK's lubricity has enabled Daido to eliminate the use of oil lifters, which are required on machines using white metal-based bearings.

"This makes it possible to streamline related equipment and maintenance," adds Ragan. "And, because Victrex PEEK has superior chemical resistance, it is possible to eliminate any bearing insulation."