单项选择题
A.eye B.hole C.balance holes D.opening
Which one is not the normal operation for boiler shutdo...
单项选择题Which one is not the normal operation for boiler shutdown?（）
A.Carry out soot blowing if permissible B.Change fuel supply to diesel oil C.Close steam stop valves on boiler when pressure is reduced D.Drain boiler empty when it has cooled down
The forced draught fan should be started and air passed...
单项选择题The forced draught fan should be started and air passed through the furnace for several minutes to “（）” it of any exhaust gas or oil vapors.
A.blow B.clean C.scavenge D.purge
A shallow dish positioned at the normal water level is ...
单项选择题A shallow dish positioned at the normal water level is connected to the（）This enables the blowing down or removal of scum and impurities from the water surface.
A.main stern stop valve B.auxiliary steam stop valve C.scum valve D.blow down valve
