无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

<i id="kv7ot"></i>

<ruby id="kv7ot"><small id="kv7ot"></small></ruby><em id="kv7ot"></em>

<sup id="kv7ot"><legend id="kv7ot"><div id="kv7ot"></div></legend></sup>

單項(xiàng)選擇題

The（）is fitted in the main steam supply line and is usually of the non-return type.

A.main steam stop valve
B.auxiliary steam stop valve
C.feed check or control valve
D.blow down valve

你可能感興趣的試題

單項(xiàng)選擇題

The lifting pressure of （） is set in the presence of a Surveyor it is locked and cannot be changed.

A.fuel valves of main engine
B.injector pump of main engine
C.safety valves of marine boiler
D.safety valves of a reciprocating pump

單項(xiàng)選擇題

The propeller is pushed on to the tubeshaft taper and made tight by（）

A.a mechanical seal
B.keyway and key
C.a nut
D.shrinkage

<ruby id="crtqu"><small id="crtqu"></small></ruby>