Maritime Knowledge Base
Browse questions and answers across marine machinery, merchant navy careers, shipboard operations and maritime glossary terms.
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Marine Machinery
Troubleshooting guides for pumps, boilers, purifiers, compressors and auxiliary systems.
Merchant Navy Careers
Questions about joining the merchant navy, exams, cadetships, ranks and sea-time.
Maritime Glossary
Plain-English definitions of shipping, engine-room, navigation and regulatory terms.
Shipboard Operations
Practical Q&A for watchkeeping, safety, maintenance routines and onboard documentation.
Results for "Combustion"
What is an inert gas system on a tanker and why is it needed?
An inert gas system fills a tanker's cargo tanks with oxygen-poor gas so the atmosphere cannot support combustion, preventing explosions in and around the cargo.
Marine MachineryWhy is the exhaust temperature high on one main engine unit?
A high exhaust temperature on a single cylinder points to that unit's combustion, injection or exhaust valve — a deviation from the others is the key diagnostic clue.
Marine MachineryHow does a marine incinerator work and what can it burn?
A marine incinerator burns the ship's waste oils, sludge and solid garbage in a combustion chamber, subject to MARPOL rules on what may be incinerated and where.
Marine MachineryWhat is jacket cooling water in a marine engine?
Jacket cooling water is the treated fresh water circulated through the passages, or jackets, around an engine's cylinders to carry away combustion heat and keep it at its correct working temperature.
Marine MachineryWhat is scavenging in a two-stroke marine engine?
Scavenging is the process of pushing the burnt exhaust gases out of a two-stroke engine cylinder and replacing them with fresh air, ready for the next combustion cycle.
Shipboard OperationsWhat should be checked during engine-room watchkeeping rounds?
How to make an engine-room round count — comparing live readings against normal ranges and catching trends before they become failures.
Marine MachineryWhy is my main engine jacket cooling water temperature high?
Working through high jacket-water temperature — flow, the cooler, the sea and central-cooling side, thermostats, air locks and load.
Marine MachineryWhat causes a scavenge fire in a two-stroke marine engine?
A scavenge fire is the ignition of accumulated oil and carbon in the scavenge spaces of a two-stroke engine — here is why it happens and how to respond.
Marine MachineryWhat causes a marine engine turbocharger to surge?
Turbocharger surging is a violent, audible instability of the airflow through the compressor — it signals a mismatch between the turbocharger and the engine's demand.
Merchant Navy CareersWhat is an electro-technical officer (ETO) and what do they do?
An electro-technical officer is a specialist engine-department officer responsible for a ship's electrical, electronic and control systems, a rank formalised under STCW.
Marine MachineryWhy does the auxiliary boiler flame keep failing or the burner keep tripping?
Repeated boiler flame failure trips the burner on the flame monitor — the causes run through the fuel, the ignition, the air and the flame-detection system.
Marine MachineryHow does a marine diesel engine work?
A marine diesel engine converts the chemical energy of fuel into rotary motion through compression ignition — here is the working principle and the two-stroke and four-stroke cycles.
Marine MachineryHow does a marine boiler work?
A marine boiler generates steam by transferring heat to water — this covers the working principle and the difference between oil-fired and exhaust-gas boilers.
Marine MachineryHow does a marine engine turbocharger work?
A turbocharger uses the energy of the engine's exhaust gas to drive a compressor that forces more air into the cylinders, greatly increasing power and efficiency.
Marine MachineryHow does a marine air compressor work and why is it needed?
A marine air compressor squeezes air in stages to high pressure and stores it in receivers, chiefly to provide the starting air that turns large diesel engines over.
Marine MachineryWhat is cylinder lubrication in a two-stroke marine engine?
Cylinder lubrication is the separate oil supply fed onto the liner of large two-stroke engines to lubricate, neutralise fuel acids and keep the surfaces clean.
Shipboard OperationsWhat is crude oil washing (COW) on a tanker?
Crude oil washing cleans a tanker's cargo tanks during discharge by spraying them with the crude cargo itself, which dissolves clingage and reduces residue, sludge and pollution.
Shipboard OperationsHow does a fixed CO2 flooding fire-extinguishing system work?
A fixed CO2 system extinguishes a fire in a protected space such as the engine room by flooding it with carbon dioxide, which displaces the oxygen the fire needs — after everyone is evacuated.
Marine MachineryWhat is a governor on a marine engine and what does it do?
A governor automatically controls an engine's speed by adjusting the fuel supply to match the load, keeping the engine at the required revolutions or a generator at constant frequency.
Marine MachineryWhat is an indicator diagram and what does it tell the engineer?
An indicator diagram plots the pressure inside an engine cylinder against volume or crank angle, letting the engineer assess the power, condition and faults of each cylinder.
Marine MachineryHow does a ship's fuel oil system store, treat and deliver fuel to the engine?
The fuel oil system takes bunkers from the storage tanks, settles and purifies them, heats heavy fuel to the right viscosity, and delivers clean fuel under pressure to the engine.
