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The cylinder oil is pumped into the cylinder (via non-return valves) when the piston rings pass the lubricating orifices, during ______.
A.the upward stroke
B.the downward stroke
C.the power stroke
D.the suction stroke
参考答案
更多 “ The cylinder oil is pumped into the cylinder (via non-return valves) when the piston rings pass the lubricating orifices, during ______.A.the upward strokeB.the downward strokeC.the power strokeD.the suction stroke ” 相关考题
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单选题In a refrigeration system, which of the following statements describes the actions occurring when a solenoid valves, used in conjunction with an unloader head is energized?（）A
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transfer heat from the cylinder to the pistonB
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worn piston boss piston pin bearingsD
fluctuating gas pressure in the combustion space
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