一、前言分项测量锥体外螺纹各参数比测量圆柱螺纹参数要困难些,尤其是中径的测量。不少著作介绍了锥体外螺纹中径的多种测量方法,但这些方法在操作上和计算上都比较复杂。有的著作介绍了用影象法测量锥体外螺纹中径,比较简单、实用。本文再介绍几种更为简便的测量方法,供同行们参考。 First, the preface sub-item measuring conical external thread than the parameters of cylindrical thread parameters to be more difficult, especially in the diameter measurement. Many works have introduced a variety of measurement methods of the cone diameter of the external thread, but these methods are more complicated in operation and calculation. Some books introduced the use of imaging method to measure the cone diameter of the outer thread, relatively simple and practical. This article describes several more simple measurement methods for colleagues for reference.