单项选择题
A.boiler drums B.hot wells C.condensers D.evaporators
The air reservoirs must have （） fitted to prevent ruptu...
单项选择题The air reservoirs must have （） fitted to prevent rupture in the event of fire.
A.high pressure alarm B.fire alarm C.extinguishers D.fusible plugs
Before liquid can flow into a pump, the air in the suct...
单项选择题Before liquid can flow into a pump, the air in the suction line must be （） sufficiently to cause the liquid to flow into the suction chamber.
A.filled B.evacuated C.compressed D.charged
Generally speaking, suction heads require to be （） for ...
单项选择题Generally speaking, suction heads require to be （） for high speed or large capacities than for low speed or small capacities.
A.greater B.smaller C.better D.worse
