单项选择题
A.Moisture separator B.Vacuum breaker C.Lubricator D.Non-return valve
Power is defined as the （）.A.rate of doing workB.amount...
单项选择题Power is defined as the （）.
A.rate of doing work B.amount of force needed to overcome friction C.amount of work accomplished D.distance through which an object is moved
To correct the condition of slugging and flooding back ...
单项选择题To correct the condition of slugging and flooding back in a refrigeration system, it may be necessary to （）.
A.re-adjust the discharge pressure B.clean the expansion valve screen C.add refrigerant D.adjust the expansion valve
On small, low pressure, air compressors, the cylinders ...
单项选择题On small, low pressure, air compressors, the cylinders are usually lubricated by the （）.
A.splash method B.mechanical force feed lubricators C.detached sump method D.internal cooling passages in the crankshafts and connecting rods
