ASTM D5949 Test Method for Pour Point of Petroleum Products (Automatic Pressure Pulsing Method)
8. Sampling
8.1 Obtain a sample in accordance with Practice D4057 or by Practice D4177.
8.2 Samples of very viscous materials may be warmed until they are reasonably fluid before they are transferred; however, no sample shall be heated more than is absolutely necessary. The sample shall not be heated and transferred into the test specimen cup unless its temperature is 70 °C or lower.
NOTE 3 - In the event the sample has been heated above this temperature, allow the sample to cool until its temperature is at least 70 °C before transferring.
8.3 For some sample types, such as viscous lube oils that are prone to having entrained air or gas bubbles present in the sample, the use of an ultrasonic bath (see 6.8) without the heater turned on (if so equipped), has been found effective in dissipating bubbles typically within 1 min.
9. Preparation of Apparatus
9.1 Install the analyzer for operation in accordance with the manufacturer's instructions.
9.2 Turn on the liquid cooling medium, if required, and ensure its temperature is appropriate for the specimen being tested in accordance with manufacturer's instructions (see 7.1).
9.3 Turn on the nitrogen gas, if required, and ensure that it is regulated to the appropriate pressure in accordance with the manufacturer's instructions.
9.4 Turn on the main power switch of the analyzer.
10. Calibration and Standardization
10.1 Ensure that all of the manufacturer's instructions for calibrating, checking, and operating the apparatus are followed.
10.2 A sample with a well-documented pour point can be used to verify performance of the apparatus. Alternatively, a sample which has been extensively tested in a pour point interlaboratory study can be used.
