Cloud Point vs Pour Point

Cloud Point vs Pour Point

• Pour point and cloud point are two important physical properties of any fuel or lubricant.

• While cloud point refers to the temperature at which there is a presence of a wax cloud in the fuel, pour point is the lowest temperature at which the fuel can flow and below which the fuel tends to freeze or ceases to flow.

• In cold weather conditions, certain additives are added to the fuel to keep its pour point and cloud point higher.

What is Cloud Point?

In the industry, cloud point is taken as the temperature below which wax in fuel tends to form a cloudy appearance. This is a condition which is detrimental for any engine as solidified wax makes the fuel thick and it clogs the fuel filters and injectors. This wax also gets applied on the pipeline and has a tendency to form an emulsion with water. This is a property that holds great significance in cold weathers. Cloud point is also referred to as Wax Appearance Temperature (WAT).


What is Pour Point?


pour point can also be described as the lowest temperature at which a fuel performs satisfactorily and beyond this temperature, the fuel stops flowing and starts to freeze.

Read more: http://www.differencebetween.com/difference-between-cloud-point-and-vs-pour-point/#ixzz1aRTWvBXE

As oil cools to temperatures in the 40's and below, waxes in the oil will crystallize. As the oil is cooled further to freezing or below, moisture in the oil will form ice. The temperature at which these crystals form and are visible is called the Cloud Point. The greater the quantity of wax present, the higher the cloud point. Wax crystals have a different appearance than ice crystals and will form above 32° F.

If you continue to chill the oil, eventually the oil will not flow out of the test tube when turned upside down. Remember, viscosity of oil is inversely proportional to temperature. The temperature at which this occurs is call the Pour Point.