Concept of error
Geometric parameters of the part: parameters including shape, size and position, etc.
Machining error: The amount of variation of the actual geometric parameters of the part after machining to its ideal parameters.
Geometric accuracy: The actual geometric parameters approximate the ideal parameters.
The smaller the machining error of the part, the higher the machining accuracy.
The machining error of the part can be divided into the following two categories according to its geometric characteristics.
1. Dimensional error: The difference between the actual size of the part after machining and the ideal size. For example, dimensional errors in the diameter and length of shaft parts are such errors.
2. Geometric shape error: the difference between the actual geometry of the part (generally referred to as various lines, faces) and the ideal shape.
