单选题The boiler feed pump discharge pressure is higher than the steam drum pressure to （）.Aensure feed water flow into the boilerBkeep the steam drum pressure highCprevent water hammer in the feed lineDhelp the feed water flash to steam
单选题
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
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