The correct procedure for giving an auxiliary boiler a bottom blow is to begin .A.when th

职业资格 专四 已帮助 人

The correct procedure for giving an auxiliary boiler a bottom blow, is to begin .

A.when the boiler has been secured long enough for most solids to settle

B.when the boiler has been cooled to ambient temperature

C.only after raising the water level to within 0.5 inch of the high water cutout only

D.after bypassing the low pressure

请帮忙给出正确答案和分析,谢谢!

热搜:for语句中的表达式可以部分或全部省略