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單項選擇題

The（） is fitted in pair one is the main valve, the other the auxiliary or standby.

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

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單項選擇題

The（） is a smaller valve fitted in the auxiliary steam supply line, and is usually of the non-return type.

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

單項選擇題

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

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