straight hole

基本解释

The axis of a tool bar is provided with a hole which is formed by a taper hole and a straight hole;
其结构是在刀杆轴上设有一孔，该孔由锥孔和直孔构成，在锥孔内装有一锥式定位装置；
ip.com
Essentially a straight hole, the Home hole on the New has been greatly enhanced by the recent work to its bunkers.
基本上是一个直孔，孔上新房已大大加强了其最近的工作掩体。
xie.liangtao.blog.163.com
On the basis of energy method, the possibility of drill stem buckling in inclined straight hole is studied.
本文应用虚位移原理，在充分考虑钻柱所处的特殊环境的基础上，考察了斜直井眼中钻柱屈曲的可能性。

Tiny screws do not necessarily go straight into the correct hole first time after all.
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