Extended Operational and Trade Vocabulary

Engine Room Watchkeeping and UMS Operations glossary (page 2)

The engine-room watchkeeping and unattended-machinery-space vocabulary: the ABS automation notations (ACCU, ACC), AC distribution at 440 V 60 Hz, hydraulic accumulators, acoustic enclosures, and the alarm, monitoring, and control systems that permit UMS operation. Grounds each term in the watch routine and the automation standard it depends on.

638 defined terms.

Showing 250 on this page (page 2 of 3).

I

Inert gas generator: Combustion based inert gas plant for chemical and product tankers.
Inlet valve: Air admission valve on four stroke engines, set under PMS.
Insulation resistance: Megohmmeter reading on motor and cable systems, recorded in the electrical log.
Insulation test: Periodic IR check on switchboards and motors required under class survey.
Intake silencer: Acoustic enclosure on air intake of engines and compressors.
Integrated alarm system: Single alarm management platform for navigation and machinery alarms.
Intercooler: Heat exchanger between compressor stages on air compressors and turbocharger compressors of multistage type.
Internal communication: Engine room sound powered telephones and talkback per SOLAS II-1/37.
Inverter: Power electronic converter producing AC from DC, used in HVAC and shaft generator hybrids.
ISM: International Safety Management Code governing onboard procedures and maintenance.
ISO 19030: Hull and propeller performance measurement.
ISO 8217: International standard for marine fuel oil specifications.

J

Jacket cooling water: HT cooling loop around cylinder block.
Jet ejector: Steam or water driven ejector creating vacuum for fresh water generator or condenser air removal.
Jet fuel coupling: Term applied loosely to high speed quick release bunker couplings on offshore vessels.
JIS flange: Japanese Industrial Standard flange dimension used on Japanese built tonnage.
Job hazard analysis: JHA or JSA, task risk analysis tool.
Joystick control: Combined manoeuvering control of thrusters and main propulsion on DP and harbor tugs.
Jumper cable: Temporary cable bridging two switchboard points during repairs, controlled by permit.
Junction box: Enclosure terminating cables on instruments and motors, with IP rating per zone classification.

K

K factor: Cumulative cylinder oil dosage coefficient on MAN B&W ME engines.
KaMeWa: Brand of controllable pitch propellers and waterjets now part of Kongsberg.
Kelvin temperature: Absolute temperature scale used in thermodynamic calculations.
Kingsbury bearing: Tilting pad thrust bearing common on main propulsion shafting.
Kongsberg AutoChief 600: Current production main engine remote control and safety system.
Kongsberg DataChief: Integrated automation system platform for monitoring and control.
KW: Kilowatt, standard SI unit of power, used for generator and motor ratings.

L

L bend: Pipe expansion configuration absorbing thermal growth between two fixed supports.
Lambda controller: Air to fuel ratio limiter on engine governor preventing smoke during load increase.
Leak off: Drain line returning controlled leakage from injectors and high pressure pumps.
LED indicator: Solid state lamp replacing incandescent indication on modern alarm panels.
Lifeboat engine: Diesel engine in lifeboat tested weekly under SOLAS III/20.
Lift pump: Low pressure pump priming fuel system from settling tank.
Liner: Vessel operating to a published schedule on a fixed route.
Liner inspection: Drift cover removal and visual check of cylinder liner condition.
Liquid sealed manometer: U tube manometer used for low pressure measurement of scavenge and exhaust.
Load dependent cylinder lubrication: Control of cylinder oil feed rate proportional to load and fuel sulphur.
Load diagram: Engine operating envelope showing power and speed limits.
Load sharing: Equal distribution of kW and kVAr among parallel generators.
Local control stand: Manoeuvering platform at the engine with telegraph and starting controls.
Lockout tagout: Energy isolation procedure controlling work on machinery.
Log Book: Statutory ship's record.
Loss of containment: Release of fluid from a system, triggering bilge or gas alarm.
Low LO pressure alarm: Critical alarm shutting down engine if pressure falls below safety set point.
Low water alarm: Boiler drum low level alarm with separate low low cutout.
LR ACS: Lloyd's Register notation for centralized control space.
LR IBS: Integrated Bridge System notation.
LR UMS: LR Unattended Machinery Space notation.
LSFO: Low Sulphur Fuel Oil, generic term for residuals at or below 1.00% m/m sulphur.
LT cooling: Low temperature freshwater circuit cooling lube oil, charge air, and auxiliaries.
Lube oil bottom tank: Reservoir below crankcase storing engine sump oil, with level and temperature sensors.
Lube oil drip sample: Periodic engine bottom oil sample sent ashore for analysis.
Lube oil purifier: Centrifugal separator removing water and solids from system oil.

M

MAH alarm: Main air high temperature alarm on compressed air discharge.
Main air compressor: 30 bar reciprocating compressor charging the starting air bottles.
Main bearing: White metal lined bearing supporting crankshaft journals in the bedplate.
Main engine: Primary propulsion engine, slow speed two stroke on most ocean going ships.
Main lube oil pump: Engine driven or motor driven pump supplying system oil at design pressure.
Main steam stop valve: Boiler outlet valve isolating steam line.
Main switchboard: Primary distribution board receiving generator output.
Maintenance planning system: PMS, software scheduling tasks by running hours, calendar, or condition.
MAN B&W G80ME-C: Ultra long stroke electronically controlled two stroke engine.
MAN B&W K98ME: Large bore two stroke engine, common on Panamax and post Panamax container ships.
MAN B&W L60MC: Long stroke mechanical two stroke engine of earlier generation.
MAN B&W ME-B: Camshaft controlled exhaust valve with electronic fuel injection, simplified ME variant.
MAN B&W ME-C: Standard electronically controlled two stroke engine.
MAN B&W ME-GI: Dual fuel two stroke engine burning LNG with high pressure gas injection.
MAN B&W ME-LGI: Dual fuel two stroke engine burning methanol or LPG with liquid gas injection.
MAN B&W S60MC-C: Super long stroke conventional two stroke engine.
MAN B&W S70ME-C: Electronically controlled super long stroke two stroke engine.
MAN L23/30H: Medium speed auxiliary engine widely fitted on bulk carriers and tankers.
MAN L27/38: Medium speed engine for propulsion and generator service.
MAN L32/40: Medium speed four stroke engine for main and auxiliary duty.
MAN L48/60: Larger medium speed engine for cruise and ferry main propulsion.
MAN V51/60DF: Dual fuel four stroke engine for power generation and propulsion.
Mandatory continuous survey: Class regime allowing engine items to be examined progressively.
Maneuvering platform: Local engine control station with telegraph and lever controls.
Manhole: Bolted access opening on tanks and pressure vessels for inspection.
MAPOL plan: Common shorthand for the SOPEP and shipboard marine pollution emergency plan.
MARORKA: Onboard energy and performance monitoring system widely fitted on container ships.
MARPOL Annex I: Prevention of pollution by oil.
MARPOL Annex IV: Prevention of pollution by sewage.
MARPOL Annex V: Prevention of pollution by garbage.
MARPOL Annex VI: Air pollution and energy-efficiency annex.
Masthead light: Navigation light powered from emergency switchboard.
MCR: Maximum continuous rating, the highest power for continuous operation.
MDO: Marine diesel oil, distillate fuel per ISO 8217 DMB.
Mechanical seal: Spring loaded face seal on pump shafts.
Medium speed engine: Four stroke engine in the 400 to 1000 rpm range.
Megger: Insulation resistance tester used on motors and switchgear.
MEPC.107(49): IMO resolution on 15 ppm bilge separators and bilge alarms.
MEPC.108(49): IMO standard for sewage treatment plants under MARPOL Annex IV.
MEPC.244(66): Standard specification for shipboard incinerators.
Methanol Bunkering: Supply of methanol as marine fuel.
MGO: Marine gas oil, distillate fuel per ISO 8217 DMA.
Micron rating: Filter element size, absolute or nominal, specified for fuel and lube oil filtration.
Mimic display: Graphical system diagram on operator stations showing live values and alarms.
Misalignment: Deviation of shafting from straight line, measured by dial gauges or laser.
Mist detector: Oil mist detection unit, Schaller Visatron or Specronix, sampling crankcase atmosphere.
MO: Class Nippon Kaiji Kyokai notation for unattended machinery space at sea, equivalent to UMS.
Modbus: Serial fieldbus protocol common in marine automation.
Monkey island: Top deck above wheelhouse, referenced for funnel and antenna routing.
Motor controlled center: Group starter assembly feeding engine room motors.
Motorman: Engine room rating supporting watchkeeping under STCW III/4.
MSDS: Material safety data sheet for chemicals carried in ER stores.
MSV: Main steam valve, the boiler outlet stop valve.

N

NACOS: Wartsila navigation, automation, and control system suite.
National Marine Manufacturers Association: Industry body referenced for some auxiliary equipment standards.
Net calorific value: Lower heating value of fuel, used for engine performance calculations.
Neutral grounding resistor: NGR limiting earth fault current on HV systems.
NK M0: Older numeric form of the NK MO notation in some documents.
NK MO: Nippon Kaiji Kyokai class notation for unattended machinery space.
NMEA 0183: Marine electronics serial data standard.
No flow alarm: Alarm on lube or cooling system indicating loss of circulation.
NOx Technical Code: Issued under MARPOL Annex VI.
Nozzle plate: Boiler superheater header plate, also turbocharger nozzle ring.
Nozzle ring: Stator vanes directing exhaust onto turbocharger turbine wheel.
NPSH: Net positive suction head required by pumps to avoid cavitation.

O

OBA: Oil based analysis program for engine oils, run quarterly on most ships.
Observation tank: Small tank between cooler and engine collecting drips for inspection of leakage origin.
Off-Hire: Period under a time charter during which hire ceases due to specified events.
Oil discharge monitor: ODME measuring oil content in tanker washwater discharge per MEPC.108(49).
Oil mist detector: OMD continuously monitoring crankcase atmosphere, types include Schaller Visatron VN 116/87 and Specronix.
Oil Record Book Part I: Machinery space operations on all ships of 400 GT and above.
Oil Record Book Part II: Cargo and ballast operations on oil tankers of 150 GT and above.
Oily water separator: OWS, gravity coalescer or membrane unit producing effluent below 15 ppm.
One off survey: Special class survey conducted for major repairs or after incidents.
Onload tap changer: HV transformer tap selection without de-energizing, rare on ships.
OPA 90: Oil Pollution Act 1990, US oil pollution liability statute.
Open loop scrubber: Exhaust gas cleaning system using once through sea water under MEPC.340(77).
Operating console: ECR workstation with mimic, alarm list, and manual control buttons.
Order book: Total tonnage on order at shipyards.
Outboard sea chest: Sea water inlet on the side shell, alternative to bottom sea chest.
Overhauls: Scheduled maintenance involving disassembly, per PMS intervals.
Overload trip: Generator or motor protection tripping on overcurrent.
Overspeed trip: Mechanical/electrical trip on engine overspeed.

P

Packing gland: Stuffing box arrangement on stern tube and reciprocating pump rods.
Pad Eye: Welded plate with hole forming a lashing point.
Parallel operation: Two or more generators sharing load, controlled by sync check relay.
Peak pressure indicator: PMI unit measuring cylinder maximum pressure for combustion analysis.
Periodic Survey: General term for scheduled class or statutory surveys.
Piston cooling oil: System oil routed up the piston rod to internal cooling spaces in MAN B&W and Wartsila engines.
Piston cooling water: Older arrangement on engines such as Sulzer RND using fresh water for piston cooling.
Piston rings: Compression and oil control rings sealing combustion gases against the liner.
Piston rod gland: Stuffing box at bedplate top sealing piston rod between scavenge and crankcase space.
Pitot tube: Differential pressure device for flow measurement on cargo lines.
Planned maintenance system: PMS, software issuing job cards by hours, calendar, or condition.
Plate cooler: Plate heat exchanger common for central cooling and lube oil service.
Plate freezer: Refrigeration installation on fishing vessels for product freezing.
PLC: Programmable logic controller, foundation of modern marine automation.
PMS work order: Job card raised by the PMS system and signed off after completion.
Polishing filter: Final filter on lube oil system, often centrifugal type.
Pollution prevention equipment: OWS, STP, and incinerator collectively under MARPOL.
Port Engineer: Shore-based technical operations role.
Power management system: PMS auto load function starting and stopping generators with load.
Pre lubrication: Slow turning under LO pressure prior to firing the engine.
Pre warming: Circulation of hot JW through engine before start.
Pressure regulating valve: Self acting valve maintaining downstream pressure setpoint.
Pressure switch: On off device used in starting circuits and alarms.
Pressure transmitter: 4 to 20 mA device feeding the ECMS.
Primary cell: Battery used for emergency telephones and starting of emergency generator solenoids.
Prime mover: Engine or turbine driving a generator or propeller.
Probiotic STP: Sewage treatment plant using biological aerobic digestion to meet MEPC.227(64).
Proximity switch: Inductive sensor used on shaft speed and valve position feedback.
PTH: Power take home, propeller drive by shaft generator motor mode in dead engine condition.
PTI: Power take in, electric motor assist to shaft propulsion.
PTO: Power take off, shaft generator operation drawing power from the propeller shaft.
Pull up alarm: ECR notification when alarm count or load exceeds normal range.
Pulse turbocharging: Exhaust system with narrow pipes preserving pulse energy to the turbocharger.
Purifier: Centrifuge with water seal removing free water and solids from fuel oil.
Push button starter: Local pushbutton initiating motor start through MCC.

Q

Quick acting valve: Lever operated valve closing rapidly, fitted on engine room tank outlets per SOLAS II-2/4.
Quick coupling: Snap connection on bunker hoses, less common on large tonnage.
Quick-Closing Valve: Engine-room safety valve required by SOLAS.
Quill: Tube delivering cylinder oil from lubricator to the liner.

R

R134a: HFC refrigerant common in AC plants, phased down under MARPOL Annex VI Regulation 12.
R404A: HFC blend used in provision and reefer refrigeration.
R407F: Lower GWP HFC blend used as drop in for R404A.
R410A: HFC blend used in some AC plants.
R507: HFC blend used in low temperature refrigeration.
R717: Ammonia refrigerant used on reefer carriers and some chillers.
R744: Carbon dioxide refrigerant used in modern reefer container and cruise installations.
Range setting: Calibration of transmitter zero and span for the ECMS.
Rapson slide: Crosshead arrangement converting hydraulic ram travel into rudder rotation in ram type steering gear.
RC Computer Aided Operations: Brand of integrated automation system installed on numerous bulk carriers.
Reach rod: Mechanical linkage extending valve operation to remote position.
Reciprocating compressor: Piston type air compressor used for starting and service air.
Recovery boiler: Exhaust gas boiler downstream of the main engine economizer.
Reduction gear: Gearbox lowering engine speed to propeller speed on medium speed installations.
Reefer plant: Refrigeration installation for cargo, provisions, or containers.
Refractometer: Instrument measuring boiler water condensate quality from chlorides.
Refrigeration log: Daily record of compressor suction, discharge, oil pressure, and condenser conditions.
Relief valve: Spring loaded valve preventing system overpressure.
Remote control: Telegraph or ICMS based control of the engine from bridge or ECR.
Residual chlorine: Disinfection parameter on potable water and treated sewage.
Resistance temperature detector: RTD, Pt100 or Pt1000 element common on engine thermocouples.
Reverse osmosis: Membrane fresh water generator producing potable water from sea water.
Reverse power relay: Generator protection tripping on reverse kW flow.
RINA AUT-CCS: Notation for centralized control with attendance.
RINA AUT-UMS: Italian classification society notation for unattended machinery space.
Ring valve: Plate valve in reciprocating compressor.
Rocker arm: Lever transmitting cam motion to valve stem on four stroke engines.
Roll on roll off ferry: Vessel with vehicle decks and specific ER fire detection requirements.
Rotary vane steering gear: Compact steering gear with vanes inside a stator providing rudder torque.
Round of inspection: Engine room walkdown by the watch engineer.
Routing alarm: Diversion of alarm signals to cabins or duty engineer pager.
RPM indicator: Tachometer showing engine or shaft speed.
Running hours counter: Hour meter on machinery linked to PMS for maintenance scheduling.
Running light: Indication that machinery is operating, distinct from alarm or fault lights.

S

SACM Diesels: French marine engine builder, now part of MAN, historically supplied UD45 engines.
Safety system: Independent shutdown system meeting IACS UR M36.
Scavenge air: Air admitted to the cylinder during scavenging of exhaust gases in two stroke engines.
Scavenge fire: Combustion in the scavenge space due to oil and unburnt fuel accumulation.
Scavenge port: Slot in liner admitting air from scavenge receiver.
Schaller Visatron VN116/87: Widely fitted oil mist detector on MAN B&W and Wartsila engines.
SCR: SAR Cooperation Plan required under SOLAS Chapter V Regulation 7.3 for passenger ships.
Screw pump: Twin or triple screw positive displacement pump used for fuel and lube oil.
Sea chest: Hull recess for seawater intake.
Sea watch: Engineering watch maintained at sea, manned or under UMS regime.
Sea water cooling pump: Centrifugal pump supplying central or direct cooling system.
Second Engineer: Engine department officer below chief engineer.
Selector switch: Manual switch choosing source, mode, or duty unit.
Self-priming pump: Pump capable of evacuating air from its suction line.
Service air: Compressed air supply at around 7 bar for workshop and pneumatic tools.
Service tank: Settled and purified fuel tank ready for use, also called day tank.
Settling tank: Heated tank that allows water and solids to fall out before centrifuging.
Sewage Treatment Plant: Approved under MEPC.227(64).
Shaft earthing: Brush riding on shaft to drain galvanic current to hull.
Shaft generator: Generator driven by main engine via PTO.
Shaft horsepower: SHP, power transmitted along the shaft to the propeller.
Shaft seal: Stern tube seal arrangement, brand examples include Wartsila Sterntube and Simplex Compact.
Sheave: Grooved wheel of a block.
Shore connection: physical cable between shore power and ship.
Shore power: OPS or cold ironing infrastructure, IEC/IEEE 80005 series.
Sight glass: Transparent flow indicator on cooling and fuel lines.
Slop Tank: Tank for oily residues under MARPOL Annex I.
Slow turning: Function commanding engine to rotate slowly on starting air before firing.
Sludge tank: Tank for engine and separator sludges.
Slug catcher: Vessel in gas systems separating liquid slugs from gas, used on LNG vessels.
Smoke detector: Optical or ionization sensor in machinery spaces under SOLAS II-2/7.
Smoke indicator: Funnel mounted opacity meter such as Bosch or Sigrist.
SOLAS II-1/29: Steering gear performance requirement of 35 to 30 deg in 28 seconds at maximum service draft.
SOLAS II-1/41: Main and emergency source of electrical power requirement.
SOLAS II-1/43: Emergency source requirement for cargo ships.
SOLAS II-1/45: Precautions against shock, fire, and other hazards of electrical origin.
SOLAS II-1/46: Operational requirement for periodically unattended machinery spaces.
SOLAS II-1/47: Fire precautions for periodically unattended machinery spaces.
SOLAS II-1/48: Protection against flooding for unattended machinery spaces.
SOLAS II-1/49: Bridge control of propulsion machinery for unattended spaces.
SOLAS II-1/50: Communications between bridge and machinery spaces.