5.1 This test method can be used to determine antiwear properties and coefficient of friction of EP lubricating oils at selected temperatures and loads specified for use in slip-rolling contacts in which high-speed vibrational or start-stop motions are present for extended periods of time under initial high Hertzian line contact pressures. It has found application as a screening test for lubricants used in gears, rolling bearings or cam/follower systems. Users of this test method should determine whether results correlate with field performance or other applications. In comparison to the ball-on-disk geometry as per Test Method D6425, the initial contact pressure is better retained over test time in this roller-on-disk geometry.

1.1 This test method covers an extreme pressure (EP) lubricating oil’s coefficient of friction and its ability to protect against wear when subjected to high-frequency, linear oscillation motion. The test utilizes a roller-on-disc geometry, where the roller is inclined/deflected by 10° to the oscillating movement. The procedure is identical to that described in DIN 51834, Part 4.

1.2 This test method can also be used to determine the ability of a non-EP lubricating oil to protect against wear and its coefficient of friction under similar test conditions.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.