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 （）.A10B7C4D1
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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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 （）Awill be modulated in proportionBwill be modulated in proportion and integralCwill be modulated in proportion and differentialDwill not be modulated at all
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单选题The rate of heat transfer in a water-tube auxiliary boiler can be increased by （）.Aoperating the boiler at less than normal water levelBinstalling fins on the firesides of water-tubesCincreasing the amount of excess air to the burnersDtreating the boiler water with chemical oxygen scavengers
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单选题A distorted furnace in a fire-tube auxiliary boiler may be the result of （）Afiring for extended periods in the low fire modeBoverheating, due to waterside depositsCvarying the water level above the crown sheetDcarrying excessive alkalinity in the boiler water
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单选题The water in an auxiliary boiler should be chemically tested daily for alkalinity and（）Asoap hardnessBnitrog encontentCchloride contentDdissolved CO2
单选题The fuel oil supply system to an automatic auxiliary boiler, will automatically shutdown if the boiler （）Asteam demand is highBsalinity is highCsafety valve simmersDburner flame is extinguished
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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.AmonkeyBdonkeyCwaste heatDmain
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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 refiring of a burner in order for the （）.Afurnace to be re-purgedBelectric charge to buildup in the igniterCfuel pump to restartDdram level to stabilize
单选题The water in an operating auxiliary boiler should be tested for alkalinity and chloride content each（）.AhourBdayCweekDmonth