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 "Feed water"
Why is boiler water treated on a ship and how?
Boiler water is chemically treated and tested to prevent scale, corrosion and carryover, which would damage the boiler, reduce its efficiency and threaten safety.
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 MachineryWhat causes a fluctuating water level in a marine boiler?
Why a boiler gauge glass swings — priming, foaming, load swings, feed control and level-sensor faults — and the safety response when the true level is in doubt.
Marine MachineryWhy does the oily water separator 15 ppm bilge alarm keep activating?
The 15 ppm alarm on the oily water separator stops overboard discharge when the oil content is too high — the causes lie in the separator, the monitor or the feed.
Marine MachineryHow does a marine fresh water generator (evaporator) work?
A fresh water generator makes drinking and technical water from seawater by boiling it under vacuum using waste heat from the engine, then condensing the vapour.
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 fuel or oil purifier not separating properly?
The usual causes of poor purifier separation — feed rate, temperature, gravity disc and water seal, sludge and bowl condition — and how to work through them one at a time.
Marine MachineryWhy won't my marine air compressor build pressure?
A first-principles check for a compressor that runs but won't build pressure — valves, unloader, leaks, rings and cooling.
Marine MachineryHow does a marine centrifugal oil purifier work?
A marine purifier cleans fuel and lubricating oil by spinning it at high speed so that water and solids separate out — here is the working principle.
Marine MachineryHow does a ship's steering gear work?
The steering gear is the powered hydraulic machinery that turns the rudder in response to helm orders from the bridge, using rams or rotary vanes driven by pumps.
Merchant Navy CareersWhat is a dynamic positioning operator and how do you become one?
A dynamic positioning operator controls the system that automatically keeps an offshore vessel precisely on station, a specialised and well-paid skill built on a deck-officer background.
Shipboard OperationsWhat precautions does a ship take in heavy weather?
In heavy weather a ship reduces speed and adjusts course to ease its motion, secures everything for sea, manages ballast and stability, and guards against dangerous rolling.
Marine MachineryWhat is the difference between a controllable-pitch and a fixed-pitch propeller?
A fixed-pitch propeller has blades set at one permanent angle, while a controllable-pitch propeller can rotate its blades to vary thrust and go astern without reversing the engine.
Marine MachineryWhat is the stern tube and stern tube seal on a ship?
The stern tube is the tube through which the propeller shaft passes out of the hull; it carries the aft bearing and a seal that keeps seawater out and lubricant in.
