ASTM D5950 Test Method for Pour Point of Petroleum Products (Automatic Tilt Method)
4. Summary of Test Method
4.1 After preliminary heating, the test specimen is inserted into the automatic pour point apparatus. After starting the program, the specimen is cooled according to the cooling profile listed in Table 1 and examined at either 1 or 3°C intervals. The lowest temperature at which movement of specimen is detected, by the automatic equipment, is displayed as the pour point.
NOTE 2 - If the automatic pour apparatus's preheat option is utilized, place the test specimen into the apparatus. After starting the program, the apparatus will automatically carry out the preliminary heating.
5. Significance and Use
5.1 The pour point of a petroleum product is an index of the lowest temperature of its utility for certain applications. Flow characteristics, like pour point, can be critical for the correct operation of lubricating oil systems, fuel systems, and pipeline operations.
5.2 Petroleum blending operations require precise measurement of the pour point.
5.3 This test method can determine the pour point of the test specimen with a resolution of 1.0°C.
5.4 Test results from this test method can be determined at either 1 or 3°C intervals.
5.5 This test method yields a pour point in a format similar to Test Method D97/IP 15 when the 3°C interval results are reported.
NOTE 3 - Since some users may wish to report their results in a format similar to Test Method D97 (in 3°C intervals) the precisions were derived for the temperatures rounded to the 3°C intervals. For statements on bias relative to Test Method D97, see 13.3.
5.6 This test method has better repeatability and reproducibility relative to Test Method D97/IP 15 as measured in the 1998 interlaboratory test program. (See Section 13.)
