D5969-21 – Standard Test Method Technical Guide

ASTM D5969-21 provides a standardized accelerated test method for evaluating the corrosion-preventive properties of lubricating greases when exposed to dilute synthetic sea water environments. This standard is an extension of Test Method D1743, adapted for environments involving dilute synthetic sea water, and is critical for selecting greases for marine, offshore, and high-humidity applications.

⚙️ Test Apparatus and Specification

The apparatus for D5969-21 relies on precise, standardized components to ensure repeatability. The test utilizes a Timken bearing assembly consisting of the LM11949 cone and roller and the LM11910 cup. A motor capable of 1750 r/min drives the assembly under a thrust load applied by a 1 kg ± 0.01 kg mass through a bearing holder. The entire unit is housed within a plastic test jar designed to maintain the stringent environmental requirements of the test.