Foam

Definition

Foam - A lubricant's tendency to foam is determined by blowing air through a sample at a specified temperature and measuring the volume of foam that remains after a settling period. Foaming can result from excessive agitation, improper fluid levels, air leaks, contamination or cavitation - the pitting or wearing away of a solid surface as a result of the collapse of a vapor bubble. Foaming can cause sluggish hydraulic operation, air binding in oil pumps and tank or sump overflow.

Standard Test Method Used

ASTM D892

Reporting Measurement

mL of foam through sequence I, II and III

Amount of Sample Needed

1200 mL