Refrigerant Oils
Requirements for satisfactory refrigerant, oil rather severe. He must ensure the good lubricating properties. Viscosity should be correct for the refrigerant and the machine in which it is used. The oil must be free of moisture. Viscosity of oil, refrigerant is measured using a Universal Viscosity Test, Saybolt viscometer should be used. In this tool, oil at 100F (383C) pass through a standard Saybolt hole. Time required in seconds 60 cm oil flow through this hole is written.
The amount of moisture in the refrigerant oil can be measured by its resistance to the flow of a current of electricity through him. This is known as its dielectric properties. Good refrigerant oil must have a minimum dielectric value up to 25 000 against Another test that can be passed to the refrigerant oil is known as the ice floe test. This test is used for oils completely miscible (mix) refrigerants. (Examples of these refrigerants R-11, R-12 and R-22.) Tests performed by mixing 10% of the refrigerant with 90% of its oil. Mix in a sealed glass tube. Then he slowly cooled until flocculant (cloudy) residue wax appears.
The maximum temperature at which this occurs is written as floe point.
Oil viscosity changes with the temperature. Oil at very low temperatures cannot pour and can become one of the hard plastic. The temperature at which the oil will just flow is called the pour point. This temperature is recorded either in degrees Fahrenheit or Celsius.
Outbreaks of oil can be determined as follows. The number of oil is heated slowly, in open containers. The thermometer is used to measure the temperature of the oil. Lighted candles or other flame brought the oil to the surface when it is heated. The temperature at which the oil vapours from the surface of the burn or flash-oil outbreak.
Refrigerant oils sometimes a very small number of antifoam inhibitor to reduce foaming. Compressor parts sometimes given phosphating treatment to improve lubrication. Tricresyl phosphate is also added refrigerant oils to improve lubrication.
Some of the newer replacement refrigerants require different types of oils. Mineral oil-based lubricants can be used. Lubricants designed for these refrigerants include polyol ester, alkyl benzene and polyalkylene glycol. Testing procedures for lubricating substances, such as mineral oil. Floe checkpoint, as described above, can be used easily. Synthetic refrigerant compression lubricants dissolve with refrigerants. They are compatible with all types of materials, including metals, wire coatings, etc...
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Air-Conditioning