The Reichert Tester is a unique tool for lubricant and additives producers to test wear preventive (WP) and extreme pressure (EP) characteristics. The test is designed to determine the point of formation of a lubricating film between two test surfaces. The test starts as a sliding contact between the surfaces and progresses to being hydrodynamically lubricated due to the formation of a lubricating film between the surfaces. This change is a result of the contact geometry progressing from a point contact to an area contact.
The test is unique as the the formation of a lubricant film is primarily identified by a sudden drop (10 db ) in the screeching sound arising out of an unlubricated metal to metal contact. As soon as the area increases sufficiently (and thereby a reduction in contact pressure), a fluid film forms and separates the surfaces causing a drop in the screeching sound. The Reichert Tester by Ducom detects this drop using an acoustic sensor and electronics designed to detect the acoustic drop and cease the test for accurate scar measurements. The system requires a small amount of lubricant for each test and can test both oils and greases. It uses a pin and a friction wheel as specimens. The area of wear scar on the test pin is measured in order to calculate the load carrying capacity of the lubricant.
See some information about this tester here: Reichert Tester