ASTM D4177 Automatic Sampling of Petroleum and Petroleum Products
ASTM D4177 Standard Practice for Automatic Sampling of Petroleum and Petroleum Products
4. Significance and Use
4.1 Representative samples of petroleum and petroleum products are required for the determination of chemical and physical properties, which are used to establish standard volumes, prices, and compliance with commercial and regulatory specifications.
5. Representative Sampling Criteria
5.1 The following criteria must be satisfied to obtain a representative sample from a flowing stream.
5.1.1 For non-homogeneous mixtures of oil and water, free and entrained water must be uniformly dispersed at the sample point.
5.1.2 Grabs must be extracted and collected in a flow proportional manner that provides a representative sample of the entire parcel volume.
5.1.3 Grabs must be a consistent volume.
5.1.4 The sample must be maintained in the sample receiver without altering the sample composition. Venting of hydrocarbon vapors during receiver filling and storage must be minimized. Samples must be mixed and handled to ensure a representative test specimen is delivered into the analytical apparatus.
