更多"Impurities from the boiler water su"的相关试题:
[单项选择]Impurities from the boiler water surface can be removed through the （）.
A. safety valve
B. blow down valve
C. scum valve
D. feed check valve
[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]If an operating auxiliary boiler has a water pH reading of 7, you should （）.
A. bottom blow the boiler
B. treat the water with caustic soda
C. treat the water with chemical scavengers
D. reduce the water alkalinity to recommended readings
[单项选择]The correct pH value of boiler water is achieved by continuous addition of a suitable （） to the feed.
A. acid
B. alkali
C. salt
D. None of the above
[单项选择]The boiler water alkalinity in a coil-type auxiliary boiler should be maintained at the pH recommended by the boiler manufacturer to（）
A. precipitate silica from solution
B. reduce corrosion in the heating coil
C. prevent clogging and erosion in the coil
D. maintain zero water hardness
[单项选择]Black smoke coming from a boiler can be caused by （）.
A. low water level
B. low oil pressure
C. excessively high fuel pressure
D. an improper air/fuel ratio
[单项选择]White smoke exhausting from a diesel engine can result from （）
A. high exhaust temperature
B. high lube oil temperature
C. low turbo-charger speed
D. low cooling water temperature
[单项选择]The reciprocating pump can’t draw water from a tank may be caused by （）.
A. leaky pipe
B. opened inlet valve
C. too much water in tank
D. None of the above
[单项选择]For proper operation, auxiliary boiler feed water must have which of the following characteristics?（）
A. High oxygen concentration
B. Low pH
C. Proper alkalinity
D. All of the above
[单项选择]The boiler feed water check valves are located on the （）
A. feed pump suction line
B. hot well
C. shell of the feed heater
D. feed lines to the boiler
[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]In a （） boiler the water flows through the inside of the tubes while the hot gases pass around the outside.
A. water-tube
B. fire-tube
C. exhaust gas
D. none of the above
[单项选择]High diesel engine cooling water temperatures can be caused by （）.
A. a worn water pump
B. not enough coolant
C. air in the cooling system
D. all of the above
[单项选择]The oil （） in the discharging water from oil water separator exceeds 15 PPM without alarm, because the coil was burnt out.
A. filter
B. hole
C. pollution
D. content
[单项选择]（） is the production of pure water from sea water by evaporation and re-condensing.
A. Evaporation
B. Circulation
C. Condensation
D. Distillation
[单项选择]We use （） to distill fresh water from sea water.
A. engine
B. sea water pump
C. cylinder cooler
D. fresh water generator
