單項選擇題How can the chance of contaminating hydraulic fluid be decreased when working on hydraulic system?（）

A.clean the fittings before they are disconnected
B.Place drip pans under leaky fittings
C.Seal any cracks in lines with Permatex
D.Coat all threads with graphite oil


您可能感興趣的試卷

你可能感興趣的試題

1.單項選擇題In the design of hydraulic piping and equipment consideration is given to minimize turbulence in the hydraulic fluid, as this will cause（）

A.molecular fluid vibration
B.energy losses
C.wide pressure variations
D.mechanical damage to control valves

2.單項選擇題One function provided by a hydraulic accumulator is to（）

A.provide an area where air can separate from the oil
B.provide an area to separate solid contaminants from the oil
C.act as an oil and water separator
D.absorb shocks occurring in the system

3.單項選擇題A reservoir, as used in hydraulic systems aboard ship, is used to store hydraulic oilAnother function is to（）

A.act as a shock absorber
B.maintain the stored oil under pressure
C.act as a base or foundation for the power unit
D.eliminate pressure surges in the system

4.單項選擇題To prevent the unnecessary loading of an air conditioning system while maintaining the designed dry bulb temperature and relative humidity in an air conditioning system, you should （）

A.admit only enough fresh outside air to provide proper ventilation
B.reduce the air reheating system load
C.lower the compressor head pressure
D.operate the purge recovery unit continuously

5.單項選擇題When air is at its dew point it is at its（）

A.lowest absolute humidity
B.lowest relative humidity
C.highest absolute humidity
D.highest relative humidity