首先总结介绍了机械装备失效与事故的区别以及两者之间的关系、机械装备失效分析工作一般应遵循的程序、失效分析工作的一般过程与实施；然后重点介绍了现场勘查与失效分析的关系，并从不涉及司法鉴定和涉及司法鉴定两个方面详细介绍了失效分析中的现场勘查技术；最后分别从残骸勘查、环境勘查、受力勘查、结构勘查4个方面举例介绍了现场勘查在整个失效分析过程中的重要性。

Firstly, the difference between failure and accident of mechanical equipments and the relationship between them, the general procedures for failure analysis of mechanical equipments, and the general process and implementation of failure analysis were summarized and presented. Then the relationship between field investigation and failure analysis was emphatically introduced, and the field investigation technique in failure analysis was introduced in detail from two aspects of not involving judicial expertise and involving judicial expertise. Finally, the importance of field investigation in the whole failure analysis was exemplified with four failure examples from the aspects of wreckage investigation, environment investigation, force investigation and structure investigation, respectively.