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单选题
Before an auxiliary boiler is shutdown for an extended period of time, the water in the boiler should have a pH value of （）.
A
10
B
7
C
4
D
1
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The fuel supply system to an automatic auxiliary boiler, will be automatically shutdown if the boiler()
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The boiler water alkalinity in a coil-type auxiliary boiler should be maintained at the pH recommended by the boiler manufacturer to______.A.precipitate(使沉淀) silica （硅石）from solutionB.reduce corrosion in the heating coilC.prevent clogging and erosion in the coilD.maintain zero water hardness
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Before the seas get rough, it is a good safety practice to ______.A.secure loose gearB.move quickly about the shipC.increase lightingD.shutdown auxiliary equipment
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A firebox explosion in an automatically fired auxiliary boiler may be the result of ______.A.excessive purging before lighting offB.insufficient trail for ignition periodC.a faulty transformer in the ignition circuitD.insufficient purging before lighting off
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单选题The most common cause of scale formation in an auxiliary boiler is （）A
concentrations of calcium sulfate in the boiler waterB
fuel oil in the feed waterC
improper treatment of the feed water with calcium sulfateD
excessive feed water alkalinity
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单选题The water level of an exhaust gas boiler which is independent of the auxiliary boiler and just as the extra heating surface of it （）A
will be modulated in proportionB
will be modulated in proportion and integralC
will be modulated in proportion and differentialD
will not be modulated at all
考题
单选题In the event of a flame failure in an auxiliary water-tube boiler, you must（）A
relight the boiler immediately to prevent loss of steam pressureB
relight the fire off the brickwork as the bricks are cherry redC
purge the furnace of any combustible gases before attempting to relight the fireD
speed up the feed pump to prevent dry firing when the burner flame is reestablished
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单选题The rate of heat transfer in a water-tube auxiliary boiler can be increased by （）.A
operating the boiler at less than normal water levelB
installing fins on the firesides of water-tubesC
increasing the amount of excess air to the burnersD
treating the boiler water with chemical oxygen scavengers
考题
单选题In an auxiliary boiler steam and water system, the highest pressure will be in the （）.A
steam stop valveB
dry pipeC
feedwater systemD
generating tubes
考题
单选题Improper maintenance of an automatic auxiliary boiler oil burner could result in （）.A
fuel pump failureB
fan motor failureC
increased feedwater consumptionD
decreased boiler efficiency
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单选题A distorted furnace in a fire-tube auxiliary boiler may be the result of （）A
firing for extended periods in the low fire modeB
overheating, due to waterside depositsC
varying the water level above the crown sheetD
carrying excessive alkalinity in the boiler water
考题
单选题The water in an auxiliary boiler should be tested daily for （）.A
dissolved oxygenB
chloridesC
sludgeD
dissolved nitrogen
考题
单选题The fuel supply system to an automatic auxiliary boiler, will be automatically shutdown if the boiler （）A
salinity is abnormally highB
steam demand is too highC
water level is abnormally lowD
feedwater flow is low
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单选题The water in an auxiliary boiler should be chemically tested daily for alkalinity and（）A
soap hardnessB
nitrog encontentC
chloride contentD
dissolved CO2
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单选题The fuel oil supply system to an automatic auxiliary boiler, will automatically shutdown if the boiler （）A
steam demand is highB
salinity is highC
safety valve simmersD
burner flame is extinguished
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单选题Which one is not the normal operation for boiler shutdown?（）A
Carry out soot blowing if permissibleB
Change fuel supply to diesel oilC
Close steam stop valves on boiler when pressure is reducedD
Drain boiler empty when it has cooled down
考题
单选题A firebox explosion in an automatically fired auxiliary boiler may be the result of （）A
excessive purging before lighting offB
insufficient trail for ignition periodC
a faulty transformer in the ignition circuitD
insufficient purging before lighting off
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单选题A （） boiler is an auxiliary boiler sometimes included in a steamships installation for supplying steam to auxiliaries in port.A
monkeyB
donkeyC
waste heatD
main
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单选题After a normal, or safety shutdown, automatic combustion control systems for an auxiliary boiler are designed to prevent the immediate re-firing of a burner in order for the （）.A
furnace to be re-purgedB
electric charge to buildup in the igniterC
fuel pump to restartD
drum level to stabilize
考题
单选题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 solutionB
reduce corrosion in the heating coilC
prevent clogging and erosion in the coilD
maintain zero water hardness
考题
单选题The water in an auxiliary boiler should be tested for chloride content to determine （）.A
total dissolved solidsB
salt contaminationC
water hardnessD
chlorine contamination
考题
单选题Excessive alkalinity of the water in an auxiliary boiler can cause （）.A
caustic embrittlement of the boiler metalB
acidic corrosion of the boiler metalC
hard scale deposits on the boiler tubesD
etching of the heat exchange surfaces
考题
单选题Bottom blow valves are installed on auxiliary water-tube boilers to （）A
completely drain the boiler in an emergencyB
prevent sludge from forming in the drumC
remove floating impurities from the boiler water surfaceD
remove settled solids from the water drum
考题
单选题If the feed pump for an auxiliary boiler fails to deliver the feed water to the boiler, the cause maybe （）.A
high steam pressure in the boilerB
abnormally high feed water temperatureC
abnormally high boiler water temperatureD
steam demand exceeding feed pump capacity
考题
单选题After a normal, or safety shutdown, automatic combustion control systems for an auxiliary boiler are designed to prevent the immediate refiring of a burner in order for the （）.A
furnace to be re-purgedB
electric charge to buildup in the igniterC
fuel pump to restartD
dram level to stabilize
考题
单选题The water in an operating auxiliary boiler should be tested for alkalinity and chloride content each（）.A
hourB
dayC
weekD
month
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