单项选择题
A.Safety valves B.Water tubes C.Steam stop valves D.Blow down valves
In a （） boiler the hot gases from the furnace pass thro...
单项选择题In a （） boiler the hot gases from the furnace pass through the tubes while the water is on the outside.
A.water-tube B.fire-tube C.exhaust gas D.None of the above is true
In a （） boiler the water flows through the inside of th...
单项选择题In a （） boiler the water flows through the inside of the tubes while the hot gases pass around the outside.
A.water-tube B.fire-tube C.exhaust gas D.none of the above
The tube in a boiler should be blinded if found （）.A.sc...
单项选择题The tube in a boiler should be blinded if found （）.
A.scaled B.informed C.leaky D.deformed
