(Equivalent Test Methods: IP 49, DIN 51579, and AFNOR T66-004)
EXPLANATION
Petroleum waxes differ in hardness. Hardness may have a significant effect upon other physical properties. Needle penetration is a measurement of hardness. This method is applicable to waxes having a penetration of not greater than 250.
This test method is similar to the needle penetration method for determining the penetration of bituminous material (Test Method ASTM D5). Similar cone methods applicable to greases and to petrolatum are described in Test Methods ASTM D217 and ASTM D937, respectively.
TEST SUMMARY
The sample of wax is melted, heated to 17° C (30° F) above its congealing point, poured into a container, and then air cooled under controlled conditions. The sample is then conditioned at test temperature in a water bath. Penetration is measured with a penetrometer, which applies a standard needle to the sample for 5 s under a load of 100 g.
TEST PRECISION
Where X is penetration.
This procedure has no bias.