<label id="xlgdo"><big id="xlgdo"><pre id="xlgdo"></pre></big></label>

輪機(jī)英語單項選擇題每日一練(2019.07.25)

單項選擇題
A simple pumping system consists of a suction branch, a pump and （）.
A.a priming device
B.a discharge branch
C.a filter
D.a suction valve
單項選擇題
Thermostatic expansion valves can be adjusted for （）.
A.suction pressure only
B.head pressure only
C.superheat only
D.suction pressure and box temperature
單項選擇題
A pressure drop through the refrigerant liquid line may cause （）.
A.solenoid valve to seize
B.compressor to hunt
C.formation of flash gas in the liquid line
D.expansion valve to freeze open
單項選擇題
All of the following operating characteristics are listed on the name-plates of motors used aboard ship except the（）
A.temperature rise
B.input kilowatts
C.horsepower
D.operating voltage
單項選擇題
The power output of a turbocharged diesel engine will drop if the cooling water flow through the after-cooler is interrupted because the （）.
A.turbocharger stalls
B.exhaust pressure increases
C.air charge density decreases
D.scavenge effect increases

<li id="t31xy"></li>

<label id="t31xy"><legend id="t31xy"><li id="t31xy"></li></legend></label>