Auxiliary Machinery. Test 9 – Online Maritime Tests

In a two stage compressor you will find pistons with different diameters (one is bigger than the other).Which one of the following statements is correct ?

A big piston will give less oil content in the air.
The biggest diameter piston is the stage two piston.
A big piston will deliver dryer air into stage one.
The smallest diameter piston is the stage two piston.

Which of the following is true when comparing Plate Type with Shell and Tube Type Heat Exchangers?

Better sealing between liquids in Shell and Tube.
The capacity can easily be changed.
Physically smaller for the same capacity.
All of these.

A water content greater than 2 % is detected in a lub oil system. What is the best action to do?

Segregate the oil in a separate tank for continuous purifying.
Continuous purifying the system with the lub oil pumps running.
Boil out the water by increasing the temperature.
It is no danger before the water level reach 6-8%.

Why is the maximum pressure in a Plate Heat Exchanger usually limited to about 10 bar?

Difficult to seal plates above this pressure.
Pump capasity.
Possibility of rupturing the plates.
All the other alternatives.

What is the reason too rising cooling water temperature at outlet of individual cylinders?

Fuel pressure of fuel booster pump too high.
Cooling water spaces insufficiently vented.
Compression pressure too low.
Overload of the engine.

After obtaining permission from the duty Deck Officer, under what conditions would the process of sootblowing the boiler tubes be most beneficial?

When the boiler is firing on high rate.
When the boiler is firing on low rate.
When the boiler is firing on medium rate.
When the boiler is standing idle.

Water hammer is a shortlasting pressure peak travelling along the pipe. How can it be avoided in a cooling water system?

Operate valves gradually
Operate valves quickly
Start pump with closed valves
Start the system with open valves and empty pipes

Review Answers