Marine boilers are used for producing steam which may be used for the following except( )
A. driving auxiliary machinery
B. driving the main engines
C. heating heavy oil
D. producing drinking water
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In which of the listed components is chemical energy converted to thermal energy with regards to boiler operation?( )
A. Furnace.
B. Super-heater.
C. Steam drum.
D. Economizer.
In a water tube boiler, circulation is developed by the difference in the( )( 1 )tube length and various diameters; (2)densities of the hot and cold water
A. only ( 1 )
B. only ( 2 )
C. both ( 1 )and (2)
D. neither (1 )nor (2)
The function of a safety valve on a marine boiler is to prevent the pressure in the boiler fromrising above( )
A. design test pressure
B. maximum allowable working pressure
C. the pressure used in the accumulation test
D. the hydrostatic test pressure
Some pumps use packing as sealing gland. The gland should be( )
A. slack enough to allow slight leakage of fluid
B. slightly blocked
C. brought up tight so as not to allow any leakage
D. fitted with a relief valve