【国外标准】 Standard Test Method for Pour Point of Petroleum Products (Automatic Pressure Pulsing Method)

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 In most cases, this test method does not require the use of mechanical refrigeration apparatus (see 7.1).5.4 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 2: 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 from the temperatures rounded to the 3° intervals. For statements on bias relative to Test Method D97, see 13.3.5.5 Test results from this test method can be determined at either 1 °C or 3 °C intervals.5.6 This test method has better repeatability and reproducibility relative to Test Method D97/IP 15 as measured in the 1992 and 1998 interlaboratory test programs.41.1 This test method covers the determination of pour point of petroleum products by an automatic instrument that applies a controlled burst of nitrogen gas onto the specimen surface while the specimen is being cooled and detects movement of the surface of the test specimen with an optical device.1.2 This test method is designed to cover the range of temperatures from −57 °C to +51 °C. However, the range of temperatures included in the 1992 interlaboratory test program only covered the temperature range from  −39 °C to +6 °C and the range of temperatures included in the 1998 interlaboratory test program was from −51 °C to −11 °C. (see 13.4).1.3 Test results from this test method can be determined at 1 °C or 3 °C testing intervals.1.4 This test method is not intended for use with crude oils.NOTE 1: The applicability of this test method or residual fuel samples has not been verified. For further information on applicability, refer to 13.4.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.