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第二类驱动阀门:借助手动、电动、液动、气动来操纵动作的阀门。如闸阀,截止阀、节流阀、蝶阀、球阀、旋塞阀等。Class ii drive valve: manual, electric, hydraulic, pneumatic to control the action of the valve. Such as gate valves, globe valves, throttle valves, butterfly valves, ball valves, plug valves and so on.
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更多 “第二类驱动阀门:借助手动、电动、液动、气动来操纵动作的阀门。如闸阀,截止阀、节流阀、蝶阀、球阀、旋塞阀等。Class ii drive valve: manual, electric, hydraulic, pneumatic to control the action of the valve. Such as gate valves, globe valves, throttle valves, butterfly valves, ball valves, plug valves and so on.” 相关考题
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单选题In setting the valves on a steam-smothering system on a tanker,the master control valve to cargo tanks should be().A
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open and the individual tank valves closedC
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