Bilge system

Question 1

State 4 sources of bilge water.

Answer 1

condensation, leakage, washing, fire fighting

Question 2

What’s the capacity of each eductor in the FWD engine room, AFT engine room, and Bow Thruster?

Answer 2

FWD/AFT engine room: 120m³/h
Bow Thruster: 50m³/h

Question 3

Explain how the eductor works in removing bilge water.

Answer 3

Eductors make use of venturi effect, which requires a fast moving fluid to pass a constrict area to create vacuum. The eductor takes in seawater from the fire pump to form the fast moving fluid. The vacuum is then used to remove bilges collected at bilge wells across various compartments.

Question 4

Where are the locations of the Single Float Bilge Level Sensor and the Triple Float Bilge Level Sensor?
For the 3 Float, what occurs when bilge level rises to the 1st, 2nd, and 3rd float?

Answer 4

Single Float: All bilge wells except engine rooms
Triple Float: Bilge wells in engine rooms

1st float : RCV will automatically open
2nd float: Auto bilge pump will run automatically
3rd float: Audio and visual alarm will be sounded

Question 5

State the eductor system startup process for the engine room.

Answer 5

Step 1:
Open all valves from:
- Sea chest to fire pump 1/6 (depends on E/R) inlet
- Fire pump outlet to eductor inlet (excl. eductor inlet)
- Eductor outlet to O/B
Close firemain O/B valve and supply to firemain valve
Step 2:
- Open valves leading to compartments that require de-watering & their bilge wells
- Leave eductor inlet valve closed
Step 3:
- Start fire pump
Step 4:
- Open educator inlet valve to eductor.
Step 5:
- Close valve to eductor (suction) valve to eductor once de-watering is completed
- Stop fire pump
- Revert eductor system and valves to close setting

Question 6

State the eductor system startup process for the engine room/bow thruster.

Answer 6

Step 1:
Open all valves from:
- Sea chest to fire pump 1/6 (depends on E/R) inlet
- Fire pump outlet to eductor inlet (excl. eductor inlet)
- Eductor outlet to O/B
Close firemain O/B valve and supply to firemain valve
Step 2:
- Open valves leading to compartments that require de-watering & their bilge wells
- Leave eductor inlet valve closed
Step 3:
- Start fire pump
Step 4:
- Open educator inlet valve to eductor.
Step 5:
- Close valve to eductor (suction) valve to eductor once de-watering is completed
- Stop fire pump
- Revert educator system and valves to close setting

Question 7

Describe the flow of seawater to the bow thrustor eductor.

Answer 7

Seachest -> Engine Room Ring -> Connecting Fire Main Pipes -> Tank Deck Ring -> Connecting Fire Main Pipes -> Bow Thruster

Question 8

What is the capacity of the auto bilge pump in the FWD/AFT engine room?

Answer 8

5 m3/hr