15.10 Flashcards
What does the lubrication system do
Distribute oil to the engine bearing compartments and gearboxes
Where does wet sump store oil
In the engine
Where is dry sump oil store oil
External supply tank mounted on a engine or near the engine
2 types of oil/lubrication systems
Full flow and constant pressure
Why is the full flow the simplest type of oil supply system
It has no way of regulating oil pressure
In full flow what happens to the oil pressure if the rotor speed increases
Higher oil flow which leads to higher oil pressure
What happens to oil pressure if temperature increases
Lower viscosity which leads to lower resistance which gives lower oil pressure
What does the pressure relief valve do
Prevent oil pressure becoming too high
What 2 sides is a pressure relief valve installed
Delivery side and suction side
What is constant pressure system also called
Regulated pressure system
In a constant pressure system does oil temperature affect oil pressure
No
Most common oil system
Full flow due to simplicity and no adjustments needed during maintenance
Disadvantages of full flow system
- Large supply pump or oil pressure
- Oil temperatures rise when power reduces
Why is the exhaust turbine bearing critical lubricating point
Due to high temperatures
What does oil for bearing cooling require
Oil cooler
Oil system 3 sub systems
Storage
Distribution
Indicating
What property does silicon give the oil tank
Fire resistance
