Abstract: In order to solve the contradiction between accuracy and efficiency of the previous estimation methods for manufacturing time of similar parts, this paper proposes an easy-programming and high-precision method. Study how the manufacturing techniques influence the manufacturing time of manufacturing features and introduces the concept of manufacturing feature composite, based on this, develop five manufacturing time databases as production preparation database, feeding and blanking database, tool changing database, rough cutting database and finish cutting database. Propose the concept of manufacturing process chart and describes the drawing method. Estimating the manufacturing time of similar parts through changing the manufacturing process of historic part and using the data in the databases for calculation. The proposed estimation method is verified through the similar parts of one part family produced in a company.

Key words: variant design, manufacturing features, manufacturing feature composite, manufacturing process, manufacturing time estimation

摘要： 为了解决以往相似零件工时估算方法的精度和效率之间的矛盾，提出一种精度高且易于编程实现进而提高效率的工时估算方法。研究加工工艺对制造特征工时的影响机理，提出制造特征组合的概念，并在此基础上实现生产准备、上下料、换刀、粗加工、精加工五个工时数据库的开发。提出制造流程图的概念并描述其绘制方法。通过对历史零件制造流程图的修改及工时数据库中数据的调取计算实现对相似零件的工时估算。以某企业生产的一个零件族中相似零件的工时估算为例，验证所提出的估算方法的有效性。

关键词: 变型设计, 制造特征, 制造特征组合, 制造流程, 工时估算