AVIA101 Lecture Notes - Lecture 12: Control Rod, Camshaft, Butterfly Valve
Document Summary
4 functions of oil: cooling, lubrication, sealing, flushing. Requirements of oil: proper viscosity (resistance to flow) when heated oil expands and becomes thinner, high flash point (ignition point, low carbon content (deposits, low pour point (freezing point) If fuel is low, oil is pulled up and ignited (so flash point has to be high to withstand) Low pour point (has to be able to move when it is cold outside) Used to break-in engine, oil is granular and has no additives. Used in the first 50 hours of new engines (to wear it out- reduce friction) Only for new engines: ashless dispersant. Used to remove contaminants and take them to filter. Additives: detergents, oxidation inhibitors improves oil stability, anticorrosion additives deter corrosion (thin film that remains after oil flows over surface that prevents corrosion, pour point depressants lowers pour point temperature. Oil is forced under pressure from a pump through the hollow crankshaft (directed at camshaft)
