Failure Mode Effects Analysis(FMEA) Geneveive Lara Zarah Mae Tabor TQMChapter 19 Mr. Abelito T. Quiwa MBA
FMEA Reference Manual for an Automotive Industry
A failure modes and effects analysis (FMEA),isa procedure in operations management for analysis of potential failure modes within a system for classification by severity or determination of the effect of failures on the system. It is widely used TQM strategy for success of organization is to in manufacturing design in quality and reliability in the products industries in various phases of the product life or services early in the development cycle. cycle and is nowincreasingly finding use in Failure Mode and Effects Analysis ( FMEA) the service industry. Failure Is a methodology of analyzing potential reliability modes are any errors or defects in a problems early in the development cycle where process, design, or it is easier to take action to overcome these issues, thereby enhancing reliability throughitem, especially those that affect the customer, and can be potential or actual. Effects design.analysis refers to studying the consequences of those failures.
Reliability is a probability of survival of a product. The survival or success of a product can be characterized by a random variable. *Continuous * Discrete f(x)>= 0 and integral of f(x)dx=1
Hazard function is a measure of a product failure. The reliability can be mathematically described as: R(t)=f(t)lh(t)
• Failure rate indicates the number of failure per unit time.
Failure cause– the physical chemical, metallurgical, design defects, quality defects or other process which are basic reason for failure.Failure mode – it is the observed result of failure .Failure effect- it is all about studying the effect of failure of components or part of the system.
System- Focuses on global system functions. Design- Focuses on component & subsystems Process- Focuses on manufacturing & assembly processes Service- Focuses on service functions Software- Focuses on software functions
FMEA Reference Manual for an Automotive Industry • FMEA Team• FMEA Risk Priority Number (RPN) Technique • Risk Priority Number (RPN)
Step 1: Define the product /process & its functions.Step 2: Construct the reliability block diagram of the product/process. Step 3: Complete the header on the FMEA worksheet Step 4: List the part along with its functions
Step 5:Identify potential failure modesStep 6:Potential Effects of FailureStep 7:Assign severity number for the effectStep 8: ClassificationStep 9: Potential CausesStep 10: Probability of Occurrence
Step 11: Identify Current Controls ( Design/process)Step 12: Determine the likelihood of detection Step 13: Assign Risk Priority Number Step 14: Determine the recommended actions Step 15:Estimate the new ranks
The process of FMEA is applied to improving the process in contrast with the design in DFMEA.
FMEA RPN is more popular in the automatic industry .FMECA consist of two parts as given:* Failure Mode Effect Analysis* Criticality Analysis
The failure rate data for each part has to be calculated based on field failures. Severity Refers to the effects of the each failure modes in the system .
Item Criticality is used criticality analysis. We calculate the criticality number in each one of the failure modes of the rectifier diode. Cr ( of a part at each severity level of effect) Cr= Criticality number for a part Cm=Individual criticality numbers for thevarious failure mode having the same severity level.
Reliability of products and services is quite important for quality and TQM. In this chapter, a brief introduction to reliability covering bath curve, probability density function and sample calculation of reliability were discussed. FMEA is all bout studying the effect of failure of parts or components on the system, thus a reliability analysis tool, FMEA aimed at improving in the reliability of the products.
the FMEA requires understanding the FF:*failure mode*failure causes*failure effects
References:WikidepiaFailure mode and effect analysis booksYoutube.com