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單項(xiàng)選擇題

Strainers, sometimes called （）, are devices designed to prevent the passage of unwanted solids into or further along a system.

A.dampers
B.filters
C.stopper circuits
D.separators

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單項(xiàng)選擇題

A(n) （） is a special type of valve which prevents the passage of steam but allows condensate to pass.

A.check valve
B.non-return valve
C.steam trap
D.quick closing trap

單項(xiàng)選擇題

Fuel oil tanks must be fitted with （） that can be closed rapidly and remotely in the event of an emergency such as a fire.

A.stop valves
B.non-return valves
C.quick closing valves
D.relief valves

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