单项选择题
A.safety valve B.blow down valve C.scum valve D.feed check valve
You should frequently compare drum-mounted and remote-r...
单项选择题You should frequently compare drum-mounted and remote-reading water level indicators（） between these have contributed to failures because of overheating through shortage of water, when a boiler was being oil-fired.
A.descriptions B.discrepancies C.different D.deflections
The safety valves should be tested and adjusted when th...
单项选择题The safety valves should be tested and adjusted when the boiler survey is （）
A.completed B.carried out C.cleaned D.steamed
A donkey boiler is （）.A.one to supply steam to the main...
单项选择题A donkey boiler is （）.
A.one to supply steam to the main propulsion turbine B.an auxiliary boiler C.A and B D.neither A nor B
