General Flashcards
(7 cards)
Q1
Whilst on passage the Engine room is in UMS and a bilge alarm activates:
(a) Describe the entry procedure into the Engine Room to acknoledge the alarm (4)
(b) List the entries that will be required for the Oil Record Book for a transfer from the bilge to the holding tank (4)
(c) State TWO possible causes for a maximum vacuum and no discharge when the pump is started (4)
(d) State two possible causes for the pump to fail to pickup suction (4)
⸻
Q1: Bilge Alarm in UMS Condition
⸻
(a) Entry Procedure into the Engine Room to Acknowledge the Alarm (4 marks)
1. Acknowledge alarm at the UMS alarm panel.
2. Inform the bridge of intent to enter the engine room.
3. Follow entry permit procedures (e.g. carry key, radio, wear PPE).
4. Log entry time and reason in the Engine Room Log Book or UMS entry log.
Memory Tip: “A.I.F.L” – Acknowledge, Inform, Follow (procedure), Log
⸻
(b) Oil Record Book Entries for Transfer from Bilge to Holding Tank (4 marks)
Use Part I of the ORB (Machinery Space Operations), and record:
1. Date, time, and position of operation.
2. Tank(s) involved – from bilge tank to holding tank (name & location).
3. Quantity transferred (in m³).
4. Signature of the officer in charge of the operation.
Memory Tip: “DQTS” – Date, Quantity, Tanks, Signature
⸻
(c) Two Possible Causes for Maximum Vacuum but No Discharge (4 marks)
1. Discharge valve closed or blocked – vacuum is created, but water can’t flow out.
2. Blocked discharge line or non-return valve stuck – prevents flow despite suction.
Memory Tip: “Vacuum but no flow? Check the GO” – Gate (valve), Outlet (clogged).
⸻
(d) Two Possible Causes for Pump Failing to Pick Up Suction (4 marks)
1. Air leak on suction line – breaks vacuum, so pump can’t draw liquid.
2. Foot valve or strainer blocked – prevents flow into suction line.
Memory Tip: “No suck? Think Leak or Block”
⸻
With reference to the treatment of lubricating or fuel oil:
(a) State the functions of a purifier (4)
(b) State the functions of a clarifier (4)
(c) State TWO constructional differences found in the bowls of a purifier and clarifiers (8)
Treatment of Lubricating or Fuel Oil
(a) Functions of a Purifier (4 marks)
A purifier is a centrifugal separator used to remove two different liquid phases (usually oil and water), along with solids.
• Separates water from oil (fuel/lube) using centrifugal force.
• Removes solid impurities such as sludge, carbon, or rust.
• Improves fuel combustion efficiency (cleaner fuel).
• Protects engine components by preventing wear from contaminated oil.
Memory Tip: “Water, Waste, Work Better, Wear Less”
⸻
(b) Functions of a Clarifier (4 marks)
A clarifier is also a centrifugal separator, but it’s used to remove solids only from a single liquid phase (usually clean oil or after purification).
• Removes fine solid particles from oil.
• No water separation — used when water contamination is not expected.
• Used for polishing already cleaned oil.
• Protects filters and components by reducing particle load.
Memory Tip: “Clarifier = Clean-up crew for solids only”
⸻
(c) TWO Constructional Differences in the Bowls of a Purifier vs. Clarifier (8 marks)
- Gravity Disc (or Water Seal Disc):
• Purifier: Has a gravity disc to separate oil and water by creating a water seal.
• Clarifier: Does not have a gravity disc — it treats oil only. - Bowl Configuration:
• Purifier: Set up for two-phase separation (oil and water + solids).
• Clarifier: Set up for single-phase separation (only oil + solids).
Bonus Notes to Remember (if asked for more detail):
• In a purifier, the gravity disc diameter is chosen based on oil density.
• In a clarifier, the bowl is often fitted with a clarifier disc (dummy disc) instead of a gravity disc.
Memory Tip:
• “Purifier = Gravity disc + Two liquids”
• “Clarifier = No disc + One liquid”
⸻
With reference to the treatment of lubricating or fuel oil:
(a) State the functions of a purifier (4)
(b) State the functions of a clarifier (4)
(c) State TWO constructional differences found in the bowls of a purifier and clarifiers (
(a) The function of a purifier is to remove solid particulate and water from the fuel.
(b) The function of a clarifier is to remove solid particulate only, with slower throughput due to longer dwell time.
(c) TWO constructional differences found in the bowls of purifiers and clarifiers are:
No gravity disc in clarifiers as there’s no oil-water interface to maintain whereas a purifier has a gravity disc
A purifier has two outlets (one for clean oil and the other for water), whereas a clarifier has one outlet for clean oil.
Q3
(a) List the THREE types of Notices issued by the Maritime and Coastguard Agency (MCA) to disseminate information to ship-owners and seafarers (8)
(b) Define the relavance and importance of each of the Notices stated in (a) (10)
a) THREE types of notices issued by the Maritime and Coastguard Agency to discriminate information to ship-owners and seafarers are
Merchant Shipping Notices (MSNs)
Marine Guidance Notes (MGNs);
Marine Information Notes (MINs).
(b) MSNs – Convey mandatory information that must be complied with under UK legislation. These MSNs relate to Statutory Instruments and contain the technical detail of such regulations.
MGNs – Gives significant advice and guidance leading to the importance of the safety of shipping and life at sea and to prevent or minimize pollution from shipping.
MINs – Marine Information Notes are intended for a more limited audience e.g. training establishments or equipment manufacturers, or contain information that will only be of use for a short period, such as timetables for MCA examinations.
Describe, with the aid of a sketch, a method of remotely monitoring the contents of a fuel oil tank (16)
The fuel oil level in a tank can be measured via the ultrasonic device. An ultrasound signal is bounced off the surface of the fuel and received by an ultrasound receiver. The time taken for the signal to travel is used to calculate the ullage which then can be used to display the image
Describe, with the aid of a sketch, a method of remotely monitoring the contents of a fuel oil tank (16)
The Level Pressure Transmitters are performing tank gauging by hydrostatic pressure that is applied on the
transmitter. The direct conversion of the pressure into electrical signal is achieved by a minute deformation of
the sensor diaphragm with applied pressure which changes the electrical resistance.
With reference to main diesel engine starting air lines:
(a) Describe the main cause of starting air line explosion (8)
(b) Explain how a leaking start air valve can be identified while the engine is running (4)
(c) State four different safety devices which can be incorporated in to the starting air line to limit the damage caused by an explosion (4)
a) The main cause of starting airline explosion is the leaking starting air valve or jamming at
the open position of the valve.
Initially, the oil that is discharged from the air compressor to the starting airline system will
deposit as a thin, moist film on the internal surface of the pipes but is not ready for combustion.
If the starting air valve leaks or jams at the open position, hot gas or flame may enter the
starting air manifold, vaporise the oil and set fire to oil mist and greasy matter, which generally deposit on the surface.
At that condition, mostly arrival first start for manoeuvring time, high-pressure compressed
air coming into contact with the fire and may cause an explosion.
⸻
Starting Air Line Safety
⸻
(a) Main Cause of Starting Air Line Explosion (8 marks)
• Accumulation of oil mist or carbon particles in the starting air line.
• These deposits originate from:
• Leaking starting air valves (allowing combustion gases into the air line).
• Backfiring during starting due to improper timing or cylinder issues.
• When starting air is injected again, a mixture of oil mist and compressed air can ignite.
• The ignition of the mixture causes a violent explosion in the air manifold or pipes.
• The explosion can rupture the air pipe, cause injury, or lead to fire.
• Poor maintenance and lack of regular draining of the air line can increase risk.
• High temperatures from engine components or hot spots may ignite the mixture.
• The explosion risk is highest during engine starting, especially if multiple attempts are made.
Memory Tip:
“OIL + AIR + HEAT = BOOM”
⸻
(b) How to Identify a Leaking Start Air Valve While Engine is Running (4 marks)
1. Cylinder head temperature rises abnormally.
2. Popping sound from starting air line (audible leak).
3. Starting air pipe feels hot near that cylinder.
4. Loss of compression or performance in that unit.
Memory Tip: “Hot, Hiss, Heat, Hit”
(Hiss = sound, Heat = pipe, Hit = power loss)
⸻
(c) Four Safety Devices in Starting Air Line (4 marks)
1. Bursting disc or rupture disc – relieves pressure from explosion in manifold.
2. Flame arrestor – prevents flame from propagating through the line.
3. Non-return valve on each starting air valve – prevents backflow of gases into air line.
4. Interlock system – prevents engine from starting unless it’s in the correct condition (e.g., turning gear disengaged).
Bonus (if asked for more):
• Automatic drain valves to remove oil/water from the air line.
• Start air sequence control to ensure only one valve opens at a time.
Memory Tip: “BNFI” – Burst, Non-return, Flame arrestor, Interlock
⸻
