As the gas turbine engines have limited number of moving
components their lubrication requirements are much simpler to meet. This is
because the oil does not lubricate any parts that are directly heated by
combustion (i.e Combustion chambers, Turbine Blades/Vanes...etc)
However, for a sustained and prolonged operation, the engine requires ample
supply of lubricating oil at all the bearings, gears and driving splines. This
supply should be a continuous flow of clean filtered oil and an appropriate
temperature, pressure and viscosity, throughout the engine operation.
Main goals of engine lubricating oils are to:
- Lubricate
- Cool/ carry away the heat
- Prevent corrosion
- Resist oxidation at high
temperatures
- Possess suitable viscosity
at all operating temperatures
Gas turbine engines uses specially formulated low viscosity
synthetic oil that does not originate from mineral oil. military specification
MIL-PRF-7808 commonly referred as Type I jet oil and
MIL-PRF-23699 commonly referred as Type II Jet oil are some examples of
such synthetic aviation oils. It is essential that only those oils
specified by the engine manufacturer are used.
The ultimate decision of which oil to be used is decided by
the operation characteristics and the loads of the engine including the bearing
temperatures. Often the selection of the appropriate type of oil is a results
of multiple engine tests and lab analysis of the oil. There are wide range of
components being used in the lubrication system and basic overview is given in
the below diagram. More details of each components will be discussed in later
posts.
Following video is created to provide overview of the lubrication system :
As the gas turbine engines have limited number of moving
components their lubrication requirements are much simpler to meet. This is
because the oil does not lubricate any parts that are directly heated by
combustion (i.e Combustion chambers, Turbine Blades/Vanes...etc)
However, for a sustained and prolonged operation, the engine requires ample supply of lubricating oil at all the bearings, gears and driving splines. This supply should be a continuous flow of clean filtered oil and an appropriate temperature, pressure and viscosity, throughout the engine operation.
Main goals of engine lubricating oils are to:
- Lubricate
- Cool/ carry away the heat
- Prevent corrosion
- Resist oxidation at high temperatures
- Possess suitable viscosity at all operating temperatures
Following video is created to provide overview of the lubrication system :
