单选题Waterside scale in a fire-tube boiler may cause （）.Aincreased heat transferBfireside erosionChigh steam demandDoverheated tubes
单选题
Waterside scale in a fire-tube boiler may cause （）.
A
increased heat transfer
B
fireside erosion
C
high steam demand
D
overheated tubes
参考解析
解析：
暂无解析
相关考题：
The cooling liquid used for the cylinder may be referred to as _____.A.jacket waterB.make-up waterC.boiler waterD.flushing water
what chemicals did you use to treat the boiler water ?when you test alkalinity and acidity of water in boiler by pH test paper ? the result shows the boiler water is in acidiity . please describe what the possible cause is .
Which of the following actions may cause a trigger to be fired?() A.DROPB.ALTERC.DELETED.ROLLBACK
If the feed pump for an auxiliary boiler fails to deliver the feed water to the boiler, the cause may be ______.A.high steam pressure in the boilerB.abnormally high feed-water temperatureC.abnormally high boiler water temperatureD.steam demand exceeding feed pump capacity
Goods may be dangerous not merely by reason of the fact that they may endanger the safety of the vessel， but also because they are liable to cause the vessel to ________ ．A.detainB.be detainedC.be detainingD.detains
A bypass line provided around a waste heat auxiliary boiler in a diesel engine exhaust system, may be used to avoid boiler ______.A.corrosion at low engine loadsB.erosion at high engine loadsC.overload at high engine loadsD.scaling at all exhaust temperatures
Which statement about inert gas pressures in a cargo tank is TRUE ________．A.The pressures of the inert gas in the tank may create excessive pressure at the pump while dischargingB.Gas pressures should be maintained at the highest permissible level throughout the discharging processC.High gas pressures may cause pyrophoric oxidation in the tankD.High gas pressures may cause loss of suction when stripping
Which of the following actions may cause a trigger to be fired?（）A、DROPB、ALTERC、DELETED、ROLLBACK
单选题When lighting off an auxiliary boiler, which of the problems listed could cause the burners to sputter?（）Acold fuel oilBlow fuel oil pressureClow atomizing steam pressureDwater in the fuel oil
单选题The exhaust pipe must be gas tight throughout its entire length otherwise（）.Abilge water may enter the exhaust pipeBentry of air may cause vapor lockCcarbon monoxide may enter the interior of the vesselDthe joint gaskets may be blown
单选题The most common cause of scale formation in an auxiliary boiler is （）Aconcentrations of calcium sulfate in the boiler waterBfuel oil in the feed waterCimproper treatment of the feed water with calcium sulfateDexcessive feed water alkalinity
单选题If a diesel engine starts firing, but is unable to come up normal speed, either without load or even under a small load, the cause may be （）Ainsufficient fuel supplyBfaulty governorChigh exhaust back pressureDall of the above may cause this problem
单选题Improper cooling of a diesel engine cylinder liner due to the accumulation of scale deposits may cause （）.Alow compression pressureBincreased piston wearCincreased cylinder lube oil consumptionDpoor contact between compression rings and liner
单选题What is likely to occur when you are surging synthetic mooring lines on the gypsyhead during mooring operations?（）AThe lines may jam and then jump off the gypsyheadBIf there is sudden strain on the line，the man tending the line may be pulled into the gypsyheadCThe lines' surging may cause the vessel to surgeDThe heat generated may cause the lines to temporarily fuse to the gypsyhead
单选题Which of the following may hardness of the boiler water cause?（） (1) scale formation (2) tube failure (3) corrosionA（1）and（2）B（1）and（3）C（2）and（3）D（1），（2）and（3）
单选题Bottom blow valves are installed on auxiliary water-tube boilers to （）Aremove suspended and precipitated solids from the boiler waterBcompletely drain the boiler in an emergency situationCprevent hardened scale deposits in the water drumDremove floating impurities from the oily water surface
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
单选题The donkey boiler may be given a bottom blow （）Ato raise water levelBonly while making steamCto remove scumDwhen fire are secured
单选题Diesel engine waste heat boiler construction is usually of the fire-tube or（）Acyclone furnace boiler typeBdry back boiler typeCwater-tube typeDcritical circulation boiler type
单选题Scale and dirt accumulation in the waterside of a lube oil cooler will be indicated by a gradual increase in the lube oil（）.ATBN numberBviscosityCtemperatureDfoaming
单选题Goods may be dangerous not merely by reason of the fact that they may endanger the safety of the vessel，but also because they are liable to cause the vessel to be（）.AdespatchedBdetainedCdetectedDdelivered
单选题While troubleshooting a refrigeration system for low head pressure, liquid refrigerant flooding back from the evaporator is determined to be the causeIt may be necessary to （）.Achange the expansion valve adjustmentBreadjust the water regulating valve to increase the flow of waterCpurge air from the condenserDclean the waterside of the condenser
单选题Foaming in the steam drum may be caused by （） in a boiler.Aoxygen in the waterBpoor boiler designCdensity too highDexcessive steam demand
单选题Which of the following conditions could cause the feed pump for an auxiliary boiler to lose suction?（）AIncreased suction head pressureBDecreased feedwater temperatureCPump recirculating line being open too muchDExcessive feedwater temperature
单选题If a compressor runs continuously, the cause might be a（）Adefective thermal bulbBclogged scale trapCstuck high-pressure switchDstuck low-pressure switch
单选题Excessive alkalinity of the water in an auxiliary boiler can cause （）.Acaustic embrittlement of the boiler metalBacidic corrosion of the boiler metalChard scale deposits on the boiler tubesDetching of the heat exchange surfaces
单选题If the feed pump for an auxiliary boiler fails to deliver the feed water to the boiler, the cause maybe （）.Ahigh steam pressure in the boilerBabnormally high feed water temperatureCabnormally high boiler water temperatureDsteam demand exceeding feed pump capacity