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Pour point , Cloud point and Floc point

Pour Point

The Pour point of an oil is the lowest temperature at which the oil will flow or ‘Pour’
When tested under certain specified conditions. Of two oils having same viscosity 
One may have higher pour point than the other because of greater wax content, pour point
Of the oil should be well below the lowest temperature to be obtained in the evaporator


Cloud Point

Since all lubricating oil contains a small amount of paraffin, wax will precipitate from any oil 
If the temperature of the oil is dropped to a sufficiently low level, Because the oil becomes
Cloudy at this point, the temperature at which the wax begin to precipitate is called
Cloud point. If the cloud point of the oil is too high,wax will precipitate from the oil in the
Evaporator and EV , A small amount of wax on EV will make the system inoperative.

Floc Pont
Floc point of the oil is the temperature at which wax will start to precipitate from a mixture 
Of 90%R 12 and 10% oil by Volume , Since the oil soluble refrigerants lowers the viscosity
Of the oil and affects both pour point and cloud point the floc point of the oil is more important 
Property were oil miscible refrigerants are used

Comments

  1. Then what is difference between floc point and cloud point ??

    ReplyDelete
  2. Floc point is applicable only for the mixture of R12 and lubricating oil. However Cloud point is for all kinds of base oil, lubricant and fuel.

    ReplyDelete

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