内孔尺寸测量比外尺寸测量困难得多。与测量整个孔相比,测量半孔由于直径另一半的点不存在,因此问题更多。有人尝试过采用适当的联动装置作成测量半圆柱和半球的装置,但还没有人尝试过开发一种测量半孔的仪器。在工程工业上制造大型挖土机,材料装卸机和类似的设备的零件时,往往碰到半孔或大 Measuring bore dimensions is much more difficult than measuring outside dimensions. The problem is more than measuring the entire borehole, since measuring the half-bore does not exist because the other half of the diameter does not exist. Someone tried to make a device that measures semicircular columns and hemispheres with the appropriate linkage, but no one has ever tried to develop an instrument that measures half a hole. When manufacturing parts for large excavators, material handling machines and similar equipment in the engineering industry, they often hit half-holes or large