ASTM D6749 for pour point of petroleum products (Automatic air pressure 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 jar 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.
9. Preparation of Apparatus
9.1 Install the automatic apparatus for operation in accordance with the manufacturer's instructions.
9.2 Clean and dry the test jar, temperature sensor, and glass tube.
9.3 Turn on the main power switch of the automatic apparatus.
10. Calibration and Standardization
10.1 Ensure that all of the manufacturer's instructions for calibrating, checking, and operating the automatic apparatus are followed.
10.2 Check the position of the temperature sensor and glass tube according to the manufacturer's instructions and, when necessary, make appropriate adjustments.
10.3 A sample with a well documented pour point can be used to verify the performance of the automatic apparatus. Alternatively, a sample which has been extensively tested in a pour point interlaboratory study can be used.
