BD Marine Engineer Class 4 (Coastal CE) flashcards
BD Marine Engineer Class 4 (Coastal CE) · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Brake mean effective pressure
- The average pressure acting on the piston during the power stroke that would produce the measured brake power; calculated from brake power, engine speed and swept volume.
- Mechanical efficiency
- The ratio of brake power delivered at the shaft to indicated power developed in the cylinders; the difference is friction and pumping loss.
- Turbocharger surging
- Reversal of compressor airflow caused by excessive pressure ratio at low mass flow; produces a violent pulsation and can damage bearings and blades.
- Scavenge air
- Air supplied by the blower or turbocharger to clear exhaust gases from the cylinder and charge it with fresh air before compression begins.
- Critical speed
- A shaft rotational speed at which a natural torsional or lateral frequency coincides with the running frequency, producing resonant vibration that must be avoided.
- Fuel oil viscosity control
- Heating fuel to the temperature that gives the maker's specified viscosity at the injector, ensuring correct atomisation and adequate lubricity.
- Gravity disc selection
- Choosing the purifier disc that places the oil/water interface within the disc stack, preventing either oil loss or water carry-over into the cleaned oil.
- Steering gear 28-second rule
- The requirement that the rudder move from 35 degrees on one side to 35 degrees on the other within 28 seconds at maximum service speed.
- Oily water separator alarm
- A 15 ppm detection device that alarms and automatically stops overboard discharge when the oil content of the effluent exceeds the permitted limit.
- Synchronising a generator
- Matching voltage, frequency, phase sequence and phase angle of the incoming machine to the busbar before closing the breaker to avoid damaging currents.
- Load shedding
- Automatic disconnection of non-essential consumers when generator capacity is exceeded, preventing overload trip and total loss of electrical power.
- Integral control action
- Control output proportional to the accumulated error over time; it eliminates steady-state offset but can cause overshoot if the integral time is too short.
- Insulation resistance test
- Measurement of insulation quality with a direct-voltage tester, typically 500 V, requiring a minimum value before a circuit is energised.
- Dead-man alarm
- A timed alarm in the machinery space that must be reset by the watchkeeper at set intervals, confirming the engineer is alert and present.
- Permit to work
- A formal written authorisation controlling high-risk tasks such as enclosed space entry, hot work or isolation of electrical and pressure systems.
- Oil mist detector
- A device sampling crankcase atmosphere that alarms on a rise in oil mist concentration, warning of overheating bearings before an explosion can occur.
- Condition-based maintenance
- Maintenance scheduled from measured equipment condition such as vibration, temperature or oil analysis rather than fixed running hours or calendar intervals.
- Reserve buoyancy
- The watertight volume of the hull above the waterline; it provides the margin that keeps a damaged ship afloat after flooding.
- Free surface effect
- Loss of metacentric height caused by liquid moving freely in a partly filled tank, raising the effective centre of gravity of the ship.
- Inclining experiment
- A test shifting known weights to measure the angle of heel, from which the lightship displacement and vertical centre of gravity are calculated.
- Collision bulkhead location
- A watertight bulkhead placed between 5% of length and 3 m plus 5% of length aft of the forward perpendicular.
- Fire tetrahedron
- The four requirements for combustion: fuel, oxygen, heat and an uninhibited chemical chain reaction; removing any one extinguishes the fire.
- CO2 smothering system
- A fixed firefighting system that displaces oxygen in a sealed space; the space must be evacuated and closed before release and ventilated before re-entry.
- Emergency escape breathing device
- A small self-contained air supply of about ten to fifteen minutes, intended only to allow escape from a smoke-filled space.
- Muster station
- The designated assembly point where crew and passengers report during an abandon-ship or fire emergency for headcount and briefing.
- Oil Record Book
- A statutory record of all oil transfers, discharges, separations and bunkering operations, open to inspection by port state control officers.
- Sulphur Emission Control Area
- A designated sea area where the fuel sulphur limit is 0.10% m/m, met by compliant fuel or an approved equivalent exhaust gas cleaning system.
- Ballast water D-2 standard
- The treatment standard limiting viable organisms discharged in ballast water, achieved by an approved onboard management system rather than exchange alone.
- Designated Person Ashore
- A shore-based person with direct access to the highest management level, providing a link between the company and the ship under the ISM Code.
- STCW rest hours
- Minimum rest of ten hours in any twenty-four hour period and seventy-seven hours in any seven-day period for watchkeeping personnel.
- Port State Control detention
- Holding a foreign ship in port when deficiencies show it is unseaworthy or hazardous, until the defects are rectified to the authority's satisfaction.
- Diesel cycle efficiency
- Ideal efficiency rises with compression ratio and falls as the cut-off ratio increases, since more heat is added at constant pressure.