Abstract: There are many sorts of process knowledge and representation methods，ontology can be used in knowledge sharing and reuse here.Three tiers of process knowledge ontology are presented.The concepts related process knowledge and their tier relation are expressed to make overall views of process knowledge.By examples，the extraction of concept from process knowledge and the use of these concepts in knowledge base are illustrated.Ontology can be used to play an important role in process knowledge query.Taking machine tool as example and analyzing from the aspects of ontology modeling primitives，semantic indexing is used in process knowledge management and the indexing is realized through concept similarity calculation of knowledge ontology.Requirement of process knowledge in process planning’s different stage is presented to improve the utilization efficiency of process knowledge.Finally，the framework，development method and preliminary application of process knowledge management system are introduced，and the system is based on ontology.

摘要： 工艺知识有很多种类和表达方法，而本体可以为知识共享和重用提供手段。提出了工艺知识本体的三个层次，明确了与工艺知识有关的概念和术语的层次关系，从而形成工艺知识的整体视野。举例说明了工艺知识中领域概念的提取及其在知识库中的使用，论述了工艺知识查询时本体发挥的作用，从本体建模元语的角度分析，利用知识本体的概念相似度进行语义检索，并结合机床的例子说明其在工艺知识管理中的应用。为了提高知识利用效率，明确了面向工艺设计过程的各种工艺知识需求。最后介绍了基于本体的工艺知识管理系统的框架以及原型系统的开发方法，并进行了初步应用验证。