单项选择题
A.drill holes through the heavy side of the impeller until it balances
B.weld counterweights to the light side of the impeller
C.remove metal from the heavy side by machining in a lathe
D.acid wash and serape the heavy side until it balances
单项选择题 An axial piston, variable stroke pump is used in a vessels hydraulic steering gearUnder pressure, oil continually leaks out from between the valve plate/cylinder barrel and will（）.
单项选择题 In a flash type evaporator, all saltwater headers are vented through individual vent cocks to the（）.
单项选择题 Which of the listed characteristics of lube oil are the most important to the engineer from an operational standpoint?（）