Engine Oil tanks are the main focal point in the aircraft lubrication system. As the name implies, its main function is to provide storage for the lubrication and thermal control oil being used in the engine and its components. Oil tanks are also used for providing the additional space required for expanding fluids due to temperature rise during its operation cycles. Engine Oil tanks are usually attached to the frontal portion of the engine often called Fan cases.
Oil tanks have few major sub-assemblies which include:
- Filling port and an overflow port – For Filling / Top-up purposes
- Sight gage- To check fluid levels visually
- Oil-out / Supply port equipped with a strainer – To supply Oil to the inlet of the lubrication pump
- Drain plug – To drain the tank for emptying
- Oil-in / Return port – To connect return line from the scavenge circuit
- De-aerator / air separator – To separate any trapped air from returning oil
- Tank vent port – To provide pressure equalizing vents
- Oil level transmitter – An electronic measuring system for remote indications
- Internal walls – To strengthen the oil tank structure and also to reduce oil sloshing during operation cycles.
