游标卡尺是机械加工中必备的通用量具之一。在游标卡尺的使用中 ,因材质欠佳、制造缺陷、正常磨损、使用不当、机械损伤及变形等多种因素的影响 ,常造成游标卡尺测量误差超差。以三用游标卡尺为例 ,以下两种量爪测量面缺陷均可引起测量误差超差 :①下量爪测量面变形 ,出现锥形 Vernier caliper is one of the necessary universal measuring tools in machining. The use of vernier caliper, due to poor material, manufacturing defects, normal wear and tear, improper use, mechanical damage and deformation and other factors, often resulting in vernier caliper measurement error tolerance. Take the three-use vernier caliper as an example, the following two kinds of measuring surface defects can cause measurement error tolerance: ① lower measuring jaw deformation, taper