问题
单项选择题
在确定夹紧力方向时，夹紧力应垂直工件（）。
A、主要定位基面
B、辅助基面
C、次要定位基面
D、装配基准面
答案
参考答案：A
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在确定夹紧力方向时，夹紧力应垂直工件（）。
A、主要定位基面
B、辅助基面
C、次要定位基面
D、装配基准面
参考答案：A
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