At about 9☌ above the expected pour point, and for every subsequent 3☌, the test jar is removed from the cooling bath and tilted to check if the crude oil surface is moving. Paraffin wax crystals are formed upon cooling. As per these standards, the Crude oil specimen is cooled inside a cooling bath.
Manual Method of Pour Point Measurement:ĪSTM D97 (ISO 3016 or IP 15) standard provides the standard test methods for determining the pour point of Crude oil. There are two methods for measuring the pour point of a liquid the Manual method and the Automatic method.