What prevents water running along the shaft of a leaking centrifugal pump from entering the shaft bearing ________．A.Shaft sealB.Water flingerC.Drain holeD.Lantern ring
What prevents water running along the shaft of a leaking centrifugal pump from entering the shaft bearing ________．
A.Shaft seal
B.Water flinger
C.Drain hole
D.Lantern ring
相关考题：
A centrifugal pump may fail to deliver water when first started if the ______.A.water seal pipe is pluggedB.pump is not primedC.seal ring is properly locatedD.impeller is flooded
What is the function of wearing rings found on some centrifugal pumps ________．A.Absorb erosion of high velocity discharge streamB.Seal pump shaft against entry of airC.Isolate the outlet side from the inlet sideD.Dampen the turbulent discharge flow
The deck water seal of the inert gas system ______．A.Cools the inert gas and prevents soot from entering the cargo tanksB.Acts as an emergency shutdown when inlet pressures exceed the safe working pressureC.Prevents the backflow of hydrocarbon gasses into nonhazardous areasD.Relieves sudden large overpressures in the system
You start a centrifugal cargo pump to discharge cargo．The pump works for a while and then loses suction．This could be caused by ______．A.The pump running backwardsB.Incomplete primingC.The discharge head being too highD.All of the above
单选题If the winch should fail while you are hauling in the anchor，what prevents the anchor cable from running out?（）AChain stopperBDevil's clawCHawse ratchetDRiding pawl
单选题Shaft sealing in a centrifugal pump can be effected by （）.Athe mechanical sealBpacked stuffing boxesCeither A or BDneither A nor B
单选题What is a function of the wearing rings used in most centrifugal pumps?（）AAbsorb erosion of high velocity discharge streamBSeal pump shaft against entry of airCIsolate the discharge side from the suction sideDDampen the turbulent discharge flow
单选题Strainers are commonly used in hydraulic systems to （）.Aprotect the pump from fine soluble contaminantsBprevent solid particles from entering the pumpCprevent solid particles from entering the filterDprotect the directional control valves
单选题A double suction centrifugal pump impeller has been installed in the reverse direction, and will （）.Ahave a greater head capacityBoperate with increased impeller efficiencyCdischarge through the suction side of the pump casingDrequire more power to run the shaft
单选题A centrifugal bilge pump requires priming （）.Aprimarily to lubricate the shaft sealsBdue to the inability of this type of pump to lift water to cover the suction (eye) of the impellerCto initially unload the pump by having its head pressure equal to discharge pressureDin order to overcome the potential energy of water in the discharge line
单选题Where is the cooling water from the compensating tank in the cooling water system of main engine lead to?（）Adischarge side of the centrifugal pumpBsuction side of the centrifugal pumpCthe lowest point of the cooling water systemDinlet of the main engine
单选题The deck water seal of the inert gas system（）.Acools the inert gas and prevents soot from entering the cargo tanksBacts as an emergency system shutdown when the inlet pressures exceed the safe working pressure in the hazardous zoneCprevents the backflow of hydrocarbon gasses into nonhazardous areasDrelieves sudden large overpressures in the system
单选题One of the main functions of wearing rings, as used in a centrifugal pump, is to （）.Amaintain radial alignment between the pump impeller and casingBabsorb all impeller shaft end thrustCprevent water leakage to the atmosphereDprevent wear of the pump casing and/or impeller
单选题What is NOT a function of the air supply of a covered lifeboat?（）AProvides air for engine combustionBPressurizes water spray systemCProvides air for passenger respirationDPrevents smoke and other noxious fumes from entering craft
单选题Which one of the following is not generally recognized as one constitute of bilge water?（）AOil leaking from tanks inside engine roomBEngine room cleaning waterCWater leaking from the separator sludge tankDSewage
单选题Leakage of hydraulic fluid from around the shaft of a hydraulic motor may be caused by（）Apermanent loss of pump suctionBworn shaft sealsChigh level in the oil sumpDlow motor RPM
单选题The most suitable pump for oily water separator feed duties is （）.Aa reciprocating pumpBa vane pumpCa centrifugal pumpDa triple screw pump
单选题Where a propeller shaft passes through the hull，water is prevented from entering by means of a（）.Astuffing boxBpropeller bossCseacockDstop-water
单选题Air leakage between the shaft and stuffing box packing in a centrifugal pump is prevented by （）.Aa compressed packing glandBlantern tings between the packing ringsCa liquid sealDthe stuffing box gland
单选题If a hydraulic pump on a winch accidentally stops while hoisting，the load will stay suspended because（）.Aa check valve will close that prevents reverse circulationBa centrifugal counterweight counteracts the force of gravityCthe electric pump motor will cut outDthe control lever will move to the stop position
单选题To thoroughly pump out the bilges using a horizontally mounted centrifugal pump, the （）.Apump must always be primedBvolute must impart a radial and rotary motion of the water suction sideCconnection must guide the liquid to the lantern ringsDstuffing box should not be allowed any water leakage
单选题An axial轴向 piston pump differs from a radial piston pump as the pistons of an axial piston pump are positioned （）.Aradially from the shaftBparallel to each other and to the shaftCparallel to each other but at a right angle to the shaftDat an angle to each other and to the shaft
单选题Water accumulation in the cylinder of a secured engine is an indication that the （）Asoft water pump was not secured along with the engineBjacket water thermostat has failedCcylinder liner may be crackedDraw water pump is over-speeding just prior to engine shutdown
单选题A centrifugal pump can’t supply water after startingYou should check （）.Apriming waterBpower supplyCpacking glandDbearing lubrication
单选题Which of the following actions should be taken if during a routine maintenance inspection of a centrifugal pump, localized scoring on a pump shaft sleeve is detected?（）ACorrect the cause of the scoring and repair the sleeve or replace with a new oneBReassemble the unit and provide more water leak off for proper lubricationCCheck for parallel alignment of the sleeve radial faces to the sleeve boresDReassemble the unit and adjust the governor to obtain a slower speed
单选题Why are removable sleeves installed on centrifugal pump shafts?（）AThey make it easier to replace the pump shaft packingBThey can be economically replaced as they wear outCThey can be removed when it is necessary to lighten the weight of the pumpDThey increase the strength of the shaft
单选题The deck water seal of the inert gas system（）.Acools the inert gas and prevents soot from entering the cargo tanksBacts as an emergency shutdown when inlet pressures exceed the safe working pressureCprevents the backflow of hydrocarbon gasses into nonhazardous areasDrelieves sudden large overpressures in the system