A.decrease the velocity of gases flowing past the tubes
B.increase the rate of heat transfer
C.reduce accumulations carbon deposits
D.direct the flow of gases
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A.fuel oil supply temperature is normal
B.burner electrode is incorrectly positioned
C.fuel／air ratio is incorrect
D.ignition current is too low
A.when the boiler has been secured long enough for most solids to settle
B.when the boiler has been cooled to ambient temperature
C.only after raising the water level to within 0~5 inch of the high water cutout only
D.after bypassing the low pressure
A.completely drain the boiler in an emergency
B.prevent sludge from forming in the drum
C.remove floating impurities from the boiler water surface
D.remove settled solids from the water drum
A.defective solenoid valve
B.dirty fuel nozzle
C.grounded high tension lead
D.faulty ignition cable connector
A.excessive purging before lighting off
B.insufficient trail for ignition period
C.a faulty transformer in the ignition circuit
D.insufficient purging before lighting off
最新試題
As soon as a diesel engine has started, which of the listed engine operating parameters should be checked FIRST?（）
The condensers located in various stages of a flash evaporator are cooled by（）
During the diesel engine running, the water level of F.W expansion tank should normally kept in the （） level of glass tube.
（） is not installed on the main switchboar.
（）connectors hold best if a wire is accidentally pulled or a connection becomes loose.
A purge recovery system is used in a centrifugal air conditioning or refrigeration system to （）
Flame failure in an automatically fired auxiliary boiler can from a/an （）
The additional mark （）in the Classification Certificate for Machinery means propulsion apparatus is remotely controlled on the navigating bridge control station, and engine assembly control station is unmanned periodically.
The ISPS Code consists of a mandatory section-Part A, which shows（）
Engine parameters shall be corresponded to NOx Technical Files. This is required by （）