pour point

petroleum oil

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Last updated

July 1, 2026

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The pour point of petroleum oil is the lowest temperature at which it will flow under specific conditions. This is a critical property for the recovery and transport of crude oil, as it indicates when the oil becomes plastic and stops flowing. Pour points for crude oil can vary significantly, ranging from 32°C down to below -57°C. This is related to the cloud point, which is the temperature at which a petroleum oil begins to cloud due to wax separation upon cooling. Crude oil itself is a complex mixture of hydrocarbons with widely varying boiling and freezing points, making it impossible to assign a single common freezing point.123

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petroleum
Boiling and freezing points
However, the pour point—the temperature below which crude oil becomes plastic and will not flow—is important to recovery and transport and is always determined. Pour points range from 32 °C to below −57 °C (90 °F to below −70 °F).
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However, the pour point—the temperature below which crude oil becomes plastic and will not flow—is important to recovery and transport and is always determined. Pour points range from 32 °C to below −57 °C (90 °F to below −70 °F).
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lubrication
Pour point.
The pour point, or the temperature at which a lubricant ceases to flow, is important in appraising flow properties at low temperature. As such, it can become the determining factor in selecting one lubricant from among a group with otherwise identical properties.
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The pour point, or the temperature at which a lubricant ceases to flow, is important in appraising flow properties at low temperature. As such, it can become the determining factor in selecting one lubricant from among a group with otherwise identical properties.
Read More