SOFTENING POINT CUBE-IN-WATER METHOD: ASTM D61
TEST SUMMARY
This test method covers the determination of the softening point of pitches below 176° F (80° C). Pitches of higher softening point should be tested by Test Methods ASTM D2319 or ASTM D3104.
Two cubes of pitch, supported on wire hooks, are heated at controlled rate in water in a glass container. The softening point is defined as the mean of the temperatures at which the cubes sag downwards a distance of 25 mm.
TEST PRECISION
Repeatability: 3 ° F (1.5° C)
Reproducibility: 5°F (3°C)
This test method has no bias.
