Main machineries Flashcards
(31 cards)
What is the primary function of a marine engine?
To convert fuel into mechanical energy to propel a vessel.
What type of engine is commonly used in marine applications?
Diesel engines.
What is the purpose of a marine boiler?
To generate steam for propulsion and auxiliary machinery.
What is the main fuel used in marine boilers?
Heavy fuel oil (HFO) or marine diesel oil (MDO).
What is the term for the process of removing impurities from fuel before it enters the engine?
Fuel purification.
What is a common type of marine propulsion system?
Direct drive system.
What does the term ‘thermodynamics’ refer to in the context of marine engines?
The study of energy transfer and conversion in engines.
What is the role of the crankshaft in a marine engine?
To convert linear motion from the pistons into rotational motion.
What does the term ‘boiler pressure’ refer to?
The pressure of steam generated in the boiler.
What is a ‘steam turbine’ in relation to marine engines?
A device that converts steam energy into mechanical work for propulsion.
What is the purpose of the cooling system in a marine engine?
To maintain optimal operating temperatures and prevent overheating.
What is ‘scavenge air’ in a marine diesel engine?
Fresh air used to replace exhaust gases in the combustion chamber.
What is the function of a ‘fuel injector’ in a marine engine?
To atomize and deliver fuel into the combustion chamber.
What does ‘auxiliary machinery’ refer to on a vessel?
Supporting systems that are not primarily for propulsion, such as generators and pumps.
What is the purpose of lubrication in a marine engine?
To reduce friction and wear between moving parts.
What does ‘boiler efficiency’ measure?
The effectiveness of a boiler in converting fuel energy into steam.
What is a ‘blowdown’ in boiler operation?
The process of removing accumulated sludge and scale from the boiler.
What is the purpose of a ‘safety valve’ in a boiler?
To release excess pressure and prevent overpressure conditions.
What is a ‘marine propulsion system’?
The system that transmits engine power to the vessel’s propeller.
What is the difference between a ‘two-stroke’ and ‘four-stroke’ engine?
Two-stroke engines complete a power cycle in two strokes of the piston, while four-stroke engines do so in four strokes.
What does ‘engine RPM’ stand for?
Revolutions per minute.
What is the role of the ‘exhaust system’ in a marine engine?
To expel combustion gases safely and efficiently from the engine.
What is ‘combustion efficiency’?
A measure of how completely the fuel is burned in the engine.
What does ‘thermal efficiency’ refer to in marine engines?
The ratio of useful work output to the heat input from fuel.
