ASTM D4693 – Standard Test Method for Low-Temperature Torque of Grease-Lubricated Wheel Bearings
Description:
Significance and Use
5.1 This test method differentiates among greases having distinctly different low-temperature characteristics. This test is used for specification purposes and correlates with its precursor which has been used to predict the performance of greases in automotive wheel bearings in low-temperature service.5 It is the responsibility of the user to determine the correlation with other types of service.
Scope
1.1 This test method covers the determination of the extent to which a test grease retards the rotation of a specially-manufactured, spring-loaded, automotive-type wheel bearing assembly when subjected to low temperatures. Torque values, calculated from restraining-force determinations, are a measure of the viscous resistance of the grease. This test method was developed with greases giving torques of less than 35 N·m at −40 °C.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 WARNING—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Use Caution when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. The potential exists that selling mercury or mercury-containing products, or both, is prohibited by local or national law. Users must determine legality of sales in their location.
ASTM D4691