What is Four Ball Machine?
It is also called Four Ball Wear and EP Tester. The Four Ball machine provides an evaluation of the anti-wear and extreme pressure properties of fluid lubricants and greases in sliding contacts. The ASTM test methods are ASTM D2266 and ASTM D2596.
Why do we use Four Ball Machine?
This machine is broadly used, mainly to demonstrate performance within industrial applications like greases. The ASTM standard tests are well known in the industry and used as a reference by many lubricant formulators.
How does Four Ball Machine work?
A ball, mounted in a chuck, is rotated against three stationary balls in a pot containing the sample lubricant.