Dropping Point of Grease

Dropping point: Dropping point is an indicator of the heat resistance of grease. As grease temperature rises, penetration increases until the grease liquefies and the desired consistency is lost. Dropping point is the temperature at which a grease becomes fluid enough to drip. The dropping point indicates the upper temperature limit at which a grease retains its structure, not the maximum temperature at which a grease may be used.

A few greases have the ability to regain their original structure after cooling down from the dropping point.

ASTM D2265 - 06 (2014) Standard Test Method for Dropping Point of Lubricating Grease Over Wide Temperature Range

The dropping point is useful to assist in identifying the grease as to type and for establishing and maintaining bench marks for quality control. The results are to be considered to have only limited significance with respect to service performance because dropping point is a static test.

Cooperative testing indicates that, in general, dropping points by Test Method D2265 and Test Method D566 are in agreement up to 260°C. In cases where results differ, there is no known significance. However, agreement between the manufacturer and purchaser as to test method used is advisable.

Other procedures:

Equivalent to D566 and D2265:

IP 132
ISO 2176:1995 Petroleum products—Lubricating grease—Determination of dropping point[4]
DIN 51806

Other:

National Standard of People’s Republic of China GB/T 4929 “Test Methods for Dropping Point of Grease”[5]
S 1448(P-52)
GOST 7134-73, Method B
JIS K2220:2003 Lubricating grease
DIN 51801 Dropping Point of Lubricating Grease

ASTM D-2265 Grease Dropping Point Video