4.3故障类型影响与危险度讲述.pptVIP

故障类型影响与危险度分析Failure Mode Effect and Criticality Analysis;故障类型影响与危险度分析Failure Mode Effect and Criticality Analysis;第一节FMEA 的含义及特点;1.FMEA的含义(Failure Mode and Effects Analysis ) A procedure by which each potential failure mode in a system is analyzed to determine the results, or effects thereof, on the system and to classify each potential failure mode according to its severity. Failure Mode, Effects, and Criticality Analysis (FMECA) is a powerful design analysis tool that is used to increase system reliability. It can be applied during the initial design phase or to existing equipment. To be more effective, the FMECA should relate to the nature of the design process itself. In either case, it considers overall design, operating, and service problems, while at the same time addressing process and safety problems.;2.FMEA分析方法的特点 FMEA是通过原因来分析系统故障。即用系统工程方法，从元件的故障开始，由下向上逐次分析其可能发生的问题，预测整个系统的故障，利用表格形式，找出不希望的初始原因事件。 系统发生故障可能丧失其功能，FMEA除考虑系统中组成部分上下级的层次概念，如物理，时间空间关系，还主要考虑功能关系。从可靠性的角度看，则侧重于建立上级和下级的逻辑关系，因此FMEA是以功能为中心，以逻辑推理为重点的分析方法。;FMEA 的含义及特点;第二节 基本原理;2.故障模式(Failure mode );一般机电产品、设备常见故障类型;第二节基本原理;第二节基本原理;第二节基本原理;3.故障原因(Failure cause ) The physical or chemical process, design defects, part misapplication, quality defects, or other processes that are the basic reason for failure or which initiate the physical process by which deterioration proceeds to failure. ;第二节基本原理;第二节基本原理;第二节 基本原理;第二节 基本原理;;Failure level;An example FMEA Worksheet:;;第二节基本原理;第二节基本原理;第二节基本原理;第二节基本原理;;第三节 FMEA的分析步骤;Basic Analysis Procedure for FMEA or FMECA;Identify the function(s), failure(s), effect(s), cause(s) and control(s) for each item or process to be analyzed. Evaluate the risk associated with the issues identified by the analysis. Prioritize and assign corrective actions. Perform corrective actions and re-evaluate risk. Distribute, review and update the analysis, as appropriate.;第三节FMEA的分析步骤-说明;; 可靠性框图是研究如何保证系统正常运行的一种系统图，而不是按系统的结构顺序绘制的结构图; 一般情况下，只有构成一个系统的子系统都能正常运行，才能保证系统正常运行时，用