单项选择题

The valve that prevents water from backing out of the boiler into the feed line is the（）.

A.bottom-blow valve
B.skin valve
C.feed-check valve
D.feed-stop valve

点击查看答案&解析

上一题目录下一题

相关考题

单项选择题

The mechanical exhaust valve operation system is replaced by（）in an electronic controlled ME engine.

A.a system with a Hydraulic Power Supply (HPS) unit
B.a system with roller guides for exhaust valves
C.a system with an electronically controlled Alpha Lubricator
D.a system directly powered by electric motor

单项选择题

（）is not a feature of the electronic controlled engines.

A.Lower fuel consumption
B.Better balanced cylinder power
C.A shorter overhaul period
D.Less smoke emission

单项选择题

If a camshaft-less engine has a normal injection pressure at rated speed, the injection pressure will be at slow speed（）

A.too low
B.a little lower
C.a little higher
D.exactly the same