POUR POINT AUTO POUR POINT: ASTM D5985
EXPLANATION
This test method covers the determination of pour point of petroleum products by an automatic instrument and continuously rotates the test specimen against a suspended detection device during cooling of the test specimen. This test method includes the range of temperatures from -57 to +51° C. This test method determines the no-flow point of petroleum products by detection of the crystal structure or viscosity increase, or both, in the sample that is sufficient to impede flow of the specimen. This test method is not intended for use with crude oils. The applicability of this test method to residual fuels oils has not been verified.
TEST SUMMARY
After inserting the test specimen into the automatic pour point apparatus, and initiation of the program, the test specimen is heated and then cooled by maintaining a constant temperature differential between the cooling block and the sample. The test specimen is continuously tested for flow characteristics by rotating the test specimen cup at approximately 0.1 r/min against a stationary, counter-balanced, sphere-shaped pendulum. The temperature of the test specimen at which a crystal structure or a viscosity increase, or both, within the test specimen causes the displacement of the pendulum and is recorded with a resolution of 0.1° C. The test specimen is then heated to the original starting temperature.
TEST PRECISION
Repeatability: 2.3° C
Reproducibility: 8.7° C
