單項(xiàng)選擇題Which of the following statements is correct with regards to the operation of a centrifugal cargo pump?（）

A.Oil is discharged from the impeller through the outlet
B.Gravity causes the oil to flow toward the discharge
C.The self-priming feature of the centrifugal pump enables it to draw its own suction as it starts
D.The discharge capacity varies directly with the speed of the impeller


您可能感興趣的試卷

你可能感興趣的試題

1.單項(xiàng)選擇題The static suction head of is the （）

A.distance of the suction liquid level above the line of the pump
B.distance the suction liquid level is below the center line of the pump
C.force necessary to overcome frictional losses in the pump and piping
D.amount in inches of mercury the total suction head is below atmospheric pressure

2.單項(xiàng)選擇題A pump is defined as device that（）

A.produces pressure
B.imparts energy to a fluid to move it from level ‘A’ to level ‘B’
C.creates a vacuum to move a liquid in all installation
D.is to develop a pressure differential

3.單項(xiàng)選擇題A distorted furnace in a fire-tube auxiliary boiler may be the result of （）

A.firing for extended periods in the low fire mode
B.overheating, due to waterside deposits
C.varying the water level above the crown sheet
D.carrying excessive alkalinity in the boiler water

4.單項(xiàng)選擇題Fins are installed on the fireside of water-tubes used in waste boiler to（）

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

5.單項(xiàng)選擇題A smoking burner with a pulsating flame in auxiliary boiler, is an indication that the（）

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