Definition - What does Pour Point mean?
Pour Point is the temperature at which a liquid becomes semisolid and loses its flowing characteristics. As the paraffin content is high in crude oil, thus it has a high Pour Point. Due to the paraffin in the oil, it begins to precipitate when the temperature is lowered down to a certain level. However, oils or synthetic fibers that have high Pour Point suffer from severe screening effect and excessive pressure. It is the temperature when the liquid ceases to pour and can be determined by ASTM D-97 Pour Point test.
Petropedia explains Pour Point
Pour Point is seen in crude oils that are derivatives of kerogen II. There are two main methods used to detect the Pour Point of the liquid, i.e., manual and automatic method. Crude oil has two Pour Points that give an approximate value of the temperature window based on the thermal history. The upper Pour Point can be calculated by pouring the liquid directly into the test jar whereas the lower Pour Point can be measured by pouring the sample into the pressure vessel made up of stainless steel. As fluids lose viscosity and fluidity at a higher temperature, Pour Point depressants are added which allow the mineral oils to work efficiently.