单项选择题
A.The globe valve may be suitable for partially open operation
B.The globe valve will give full bore flow with change of direction
C.The gate valve gives full bore flow with change of direction
D.The gate valve is suitable for full bore operation only
单项选择题 The globe valve has a bulbous body, housing a valve seat and screw down plug or disc arranged at right angles to the axis of the pipeAccording to the above sentence, which of the following statements is not true?（）
单项选择题 Cocks and valves control or interrupt flow, and have internal passages arranged so that they can be restricted or closed: in cocks, by rotating the plug, and in valves, by lowering, raising or rotating a disc in relation to a seating surfaceAccording to the above sentence, which of the following statements is not true?（）
单项选择题 It should be apparent that little or nothing is gained by opening a drain at the same time as or after admitting steamThe above sentence probably means （）.