refrigeration oils

[dumpeyau]

hello people,
i am a second year refrigeration apprentice from australia and i need some help i need to know the meanings of a few terms and havent found anything as of yet.
the terms are : material compatibilty
chemical stability
pour/ floc point
floc
dielectric strength
viscosity
traction co efficent
miscibility
hygroscopic

any info woill be greatly appreciated thanks guys......

[Richard]

Hi
I can awnser some of your questions
pour/floc point is when an oil begins to wax
viscosity is the thickness of the oil
miscability is how well an oil mixes with other sustances
hydroscopic an oils ability to absorb miosture

Hope it was of some help

Richard

[Jamunda]

Is this for the Refrigeration Oils Assignment?
Because that's what I'm doing right now. I'm a first year apprentice though. It's due this Friday and I've done 130 words haha. I don't even know if I'm doing it right... It sucks...

[Jamunda]

Oh wow, you'd be a tradesman by now LOL i just realised this was posted in 2002 HAHA!

[moideen]

hello people,
i am a second year refrigeration apprentice from australia and i need some help i need to know the meanings of a few terms and havent found anything as of yet.
the terms are : material compatibilty
chemical stability
pour/ floc point
floc
dielectric strength
viscosity
traction co efficent
miscibility
hygroscopic

any info woill be greatly appreciated thanks guys......

chemical stability
for the oil to perform its lubricating functions effectively for long periodes of time,it should be stable and resist decomposition at high temperatutre.
Floc point
the refrigeration oil may contain a certain amount of paraffin.if the temperature of the oil is reduced to very low level,the wax in the oil will precipitate.the floc pont of an oil is defined as that temperature at which wax start precipitating out from a mixture of 90% refrigerant and 10% oil by volume.if an oil of a high floc pont is used, wax will seperate out at the expansion valve and restrict the flow of refrigeranrt.so a low floc point oil is necessary for use in refrigeration system.
pour point
the pour point of an oil is the temperature at which it ceases to flow.the pour point is an important consideration in selecting an oil,particularly in low temperature systems.if the pour point is too high ,the oil becomes sluggish in movement and tends to sling to the cold evaporator surfaces causing a loss in the ecaporator capacity.
A low pour point oil will have a low floc point.
viscosity
Viscosity is the amount of resistance that a fluid offers to its own flow.it is obvious that a thin oil will flow more freely than a thick oil.the thinner oil is said to be at low viscosity as compared to the thicker oil which is at a higher viscosity.
Miscibility
Miscibility of the refrigerant with oil,facilitates in the oil retaurn from the system to the compressor.
hygroscopic
the amount of affinity for water
(edited quot from the book of P.N. ANANTHA NARAYAN)


MOIDEEN-DUBAI