更多"Water evaporates or steam condenses"的相关试题:
[单项选择]Between the steam dram and the smaller water dram below, large numbers of smaller diameter （） tubes are fitted.
A. fire
B. water wall
C. generating
D. down comer
[单项选择]In an auxiliary boiler steam and water system, the highest pressure will be in the （）.
A. steam stop valve
B. dry pipe
C. feedwater system
D. generating tubes
[单项选择]When steam is being raised on a boiler, the water level will normally （）.
A. drop as the boiler warms up
B. rise as the boiler warms up
C. remain unchanged until the boiler is hot enough
D. rise and fall with the steam demand
[单项选择]The steam boiler is part of a closed loop steam, whereby, after the energy of the steam is used up and it becomes water again, （） is collected and returned back to the boiler for heating up again to steam.
A. the former
B. the first
C. the latter
D. the last
[单项选择]The load between two steam-driven alternators operating in parallel may be adjusted by varying （）
A. the speed of the alternators
B. the field strength of the machines
C. the power factor of the alternators
D. steam supply to the prime movers
[单项选择]The fuel booster pump and steam to fuel heater, together with fuel pipe heater tracer line should be shut off as soon as the （） order is acknowledged.
A. finished with engines
B. stop
C. stand by
D. full ahead
[单项选择]The boiler is fired （） the demand for steam exceeds that available from exhaust gas heating.
A. whenever
B. however
C. wherever
D. whether
[单项选择]When distilling sea water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.
A. to decrease scale formation
B. for better cooling effect
C. for more economical purpose
D. to raise vacuum
[单项选择]A water pump can not supply water after startingIt may be caused by （）.
A. closed discharge valve
B. broken pipe line
C. worn shaft
D. both A and B
[单项选择]After stopping oily water separator, sea water should be permitted for （） minutes,（）should be closed after stopping pump to reduce oxidation corrosion of inner wall.
A. 15；inlet value
B. 15；inlet and outlet value
C. 30；inlet value
D. 30；inlet and outlet value
[单项选择]The（）is fitted in the main steam supply line and is usually of the non-return type.
A. main steam stop valve
B. auxiliary steam stop valve
C. feed check or control valve
D. blow down valve
[单项选择]（）, iea steam cooler, may be filled in the boiler system to control the superheated steam temperature.
A. An economizer
B. An attemperator
C. A water dram
D. A down-comer tube
[单项选择]When distilling salt water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.
A. to cut down the amount of cooling water needed
B. to prevent an excess amount of cooling water from being discharged to the bilges
C. to supply hot water to the evaporator for more economical operation
D. None of the above is tree
[单项选择]Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）
A. double bottom fuel oil tank temperature
B. heater supply steam flow
C. pressure of the fuel supplied to the burners
D. attemperator steam flow in the heater discharge circuit
[单项选择]The water level showing in a boiler water gauge glass is usually （） during working.
A. higher than the actual drum water level
B. equal to the actual drum water level
C. increasing due to steam condensation in the glass
D. lower than actual drum water level
[单项选择]The fresh water generator produces fresh water （）.
A. by cooling sea water
B. by heating sea water
C. by evaporation of sea water
D. by purifying sea water
