单项选择题
A.pump would be very noisy B.pump would vibrate excessively C.pump would develop insufficient flow D.stuffing box would leak excessively
The packing installed in the pump stuffing box is lubri...
单项选择题The packing installed in the pump stuffing box is lubricated by （）.
A.gravity and feed oil cups B.grease cups C.hand during installation D.leakage through the stuffing box
The steam coils in a high pressure evaporator used for ...
单项选择题The steam coils in a high pressure evaporator used for saltwater service should be de-scaled with （）.
A.a needle gun B.soap and water C.a wire brush D.a chipping hammer
Which of the listed chemicals can be routinely used to ...
单项选择题Which of the listed chemicals can be routinely used to maintain the hygienic quality of potable water?（）
A.Hydrochloric acid B.Chlorine C.Sulfuric acid D.Zinc chromate
