单项选择题
The boiler feed pump discharge pressure is higher than the steam drum pressure to （）.
A.ensure feed water flow into the boiler B.keep the steam drum pressure high C.prevent water hammer in the feed line D.help the feed water flash to steam
单项选择题 If in doubt as to the true water level when a boiler is being oil-fired, you should （）.
单项选择题 The boiler feed water check valves are located on the （）
单项选择题 The water level in a steaming auxiliary boiler will always （）
