Components FMEA description

E S i c - ai it O Component/ assembly process description 9 e M a Failure Mode Description and FMEA Severity Rating (S) ... 

Assets are constructed in accordance with the Detailed Design that provides a definitive description of the systems and components required to build facilities and assemble systems in a manner that will meet the business need. During this period, construction documentation is established to provide an accurate basis for system commissioning and validation. Further, operation and maintenance plans, instructions, SOPs and SLAs are developed in readiness for the handover of the assets to the operational environment. The time required to prepare, review and obtain approval of these documents must not be underestimated and should commence as soon as the FMEA process has defined the asset management strategy. 

Column 1 describes the name of the device under review. Depending on the scope of the FMEA, this could be a component, a module or a unit. Column 2 is available to list the part number or the code number of the device under review. Column 3 describes the function of the component. A good functional description of each component can do an effective job in helping to document system operation. 

Column 1—Component Description. Enter the component description (narrative description and part number, if applicable). Note that this particular form was designed for a hardware FMEA. If a functional FMEA is being performed with this form, the component may be a subsystem, assembly, or subassembly. For some projects, breaking this column into two or three separate columns may be desirable. For example, if specific part numbers are assigned to all or most components and/or if separate item numbers are desired, a separate column (usually added as the first column with the component description becoming the second column) may be added just for item or part numbers. If the function of the component is not apparent or cannot... 

Critical items List The purpose of the FMEA is to identify and evaluate failure modes and the possible system effects of those failures. Since the potential for undesirable effects must be eliminated or controlled, the FMEA also provides recommended actions that must be taken to accomplish this goal. As part of this analysis process, the FMEA identifies any and all items within the system that, if a failure were to occur, would have a critical effect on the operation of that system. Therefore, to facilitate evaluation and analysis of these system effects, a critical items list is developed. The list provides detailed descriptive information on each item. It will explain its overall function within the system, as well as the function of any components that may make up that item. The failure mode determined as critical is then listed along with the potential effect(s) of such a failure. If an item on the critical items list is to be accepted as is, then acceptance rationale must be provided. Such rationale may include an explanation of any existing or planned design limitations that will prevent the failure during actual system operations, or the provision of excessive factors of safety that will render such fail-ure(s) extremely improbable. Another area for evaluating acceptance is the history, or lack thereof, and any known failures of systems similar in nature and operation. 

This example will develop a hardware FMEA for a proposed system that is well into the design phase of the product life cycle. For informational purposes, it is assumed that a preliminary hazard analysis was previously performed during the early stages of the design phase of this system. The information from the PHA will be used to assist in the development of the hardware FMEA. It should also be noted that the nature of a FMEA requires evaluation of subsystems, subassemblies, and/or components. For this reason, more detailed and specific descriptive information is provided here than that supplied for previous examples discussed in this text. 

FMEA uses special tables and charts to log data during the analysis. One element of a typical worksheet is a component description. The worksheet identifies the individual or combinations of components being analyzed. The worksheet has a column for failure mode. Additional columns list effects on other components and effects on the system. The... 

The method developed in this paper presents the use of Functional tree and Functional Description techniques as a starting point for the knowledge acquisition. Functional tree enables to create a functional structure that maps the relationships between the various components within the system Functional description enables to establish the interconnection between the components of the system Moreover, identifies each component function, supporting the implementation of FMEA. 

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