A.stuffing boxes eliminate the leakage problems usually associated with other gear pumps
B.it is not necessary to closely maintain design clearances with this pump
C.they are essentially self-priming and produce a high suction lift
D.these pumps are designed with extreme tooth angles
[单选题]As the displacement of a vessel increases,the detrimental effect of free surface().A . increasesB . decreasesC . remains the sameD . may increase or decrease depending on the fineness of the vessel's form
[单选题]Engine displacement is equal to the cylinder ().A . area times the strokeB . area times the stroke, times the number of cylindersC . volume times the strokeD . volume times the stroke, times the number of cylinder
[单选题]The_______in the steering gear move the rudder to the required angleA.control equipmentB.power unitC.transmission mechanismsD.fittings and pipeline
[单选题]() for the camshaft gear train is taken from a spur gear which for a six cylinder engine is at the coupling end.A . The driven gearB . The driveC . The greaseD . The lubricating oil
[单选题]Fuel pump index is ().A . the viscosity indexB . the fuel oil contentsC . the starting speedD . the reading at the rack
[单选题]第二组D.isplacement pumps are those where the volume of the pump chamber is alternately increased to draw the liquid in from the suction pipe and then decreased to force the liquid out into the delivery pipe. Centrifugal pumps are those wherein an impel
[单选题]The follow-up gear on an electro-hydraulic steering gearA.relieves excessive fluid pressureB.takes the pump off stroke when the desired rudder angle is attainedC.allows for rudder movement faster than the movement of the ship&39;sD.returns the rudder
[单选题]G.ear pumps are widely used to transfer any one of the following but .A.fuel oilB.lube oilC.hydraulic oilD.fresh water
[单选题]When transmitted by a reduction gear, diesel engine speed is reduced and the torque available for workA.remains the sameB.is reducedC.is increasedD.is eliminated
[单选题]B.efore engaging the turning gear and turning the diesel engine, which of the following operation should be done except______.A.open the indicator cocksB.supply some CYL.Oil to cylinder liner wall with lubricator (only for two stoke diesel engine)C.p