Falex Four Ball Wear & EP

This test machine is used for testing different lubricants. In each, three hard steel balls are locked in position while a fourth ball is rotated against the three others. Light loads are applied for the wear test producing a circular wear scar on each ball, and the average wear scar diameter is determined for comparison. The EP test is used to measure high load characteristics of a lubricant and is run until the balls are welded together.

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Standards and methods