Q) Write short notes on: Why pre-heating of main engine is carried out?
Ans:- Pre-heating of main engine:-
- Diesel engines are self-ignition engines i.e. fuel is injected into hot compressed air and is ignited. To obtain this, the air inside the engine should be hot which is achieved by pre-heating the engine. Pre-heating heats all parts of the engine which in turn heats the air in the cylinder.
- Pre-heating the engine also reduces cold corrosion and there are lesser thermal stresses during starting.
- Also, when engine is warm, the clearances are correct, thus lubrication is made easier and there is less chance of undue wear of moving parts.
- Pre-heating is usually done using steam or electrical heaters. Hot water is kept in circulation to engine thus keeping all parts in warm condition.