Auxiliary Machinery. Test 2 – Online Maritime Tests

Why are crankcase heaters fitted to freon compressors?

None of the mentioned alternatives.
To stop oil from thickening.
To boil off any water.
To prevent freon condensing when the compressor is stopped.

Some 4-stroke engines are fitted with a rotorcap on the cylinder head valves. For what reason?

Improve the scaling surface function, increase the service time of the exhaust valve in the engine.
Distribute the exhaust gas or the air inlet better to improve combustion.
To prevent the valve spindel to stick _____
Rotate the inlet valve during operation.

To evaluate the condition of a heat exchanger the following measurements should be recorded:

In and outlet temperatures on one media
In and outlet temperatures for both media
In and outlet temperatures, and flow rates for both media
Pressure drop

You have a brine-system onboard with steam heating for defrosting. Which liquid will You circulate first through the heater to avoid damage on the heater?

Open for the steam first to avoid freezing of condensate inside the heater.
Open carefully for the brine.
Both at the same time.
Raise the temperature on the brine.

What will You do if the liquid start raising in the Surge Drum? (Direct cooling system)

Open more on the suction valve.
Immediately reduce on the suction valve, and watch the Open more on the suction valve gauge.
Stop the compressor.
It will never happen.

During standstill liquid may condense in the crankcase or oil separator. Why is it important to heat up the oil before start?

To avoid the compressor-oil to disappear from the crankcase during starting.
The compressor will run better.
Compressor oil regulating system will operate better.
It should never be done.

Which of the below statements characterizes the most significant differences between a water-tube boiler and a fire-tube boiler during operation?

The firetube boiler does not need any non-return valves in the feedwater line circuit.
The firetube boiler has a much better capability to work at higher steam pressure.
Water-tube boilers are more efficient and contains less water. They suffer from major damages when run dry during operation.
The watertube boiler can tolerate a short period of time without any water, when the oilburner is still in action.

How do You test the probes for the 15 PPM monitor ?

By immersing them in buckets with oil and water.
They have to be changed, testing is not possible.
It is only necessary to clean them.
By immersing them in buckets with oil.

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