based on FMEA 4th Edition. Mark A. Morris. ASQ Automotive Division Webinar. November 30, [email protected] inevosisan.ga FMEA 4th Edition - Download as PDF File .pdf) or read online. Aiag Fmea 4th Edition - Download as PDF File .pdf) or read online. FMEA.
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Aiag Fmea Manual 5th inevosisan.ga - Free download Ebook, Handbook, to FMEA training based on AIAG's FMEA 4th Edition for those serving on FMEA teams. FMEA (Potential Failure Mode and Effects Analysis) 4th Edition Errata Sheet. Page Original Language (see highlight). Corrected Version Language or. AIAG's FMEA 4th Edition The Chrysler, Ford and GM's Supplier Requirements Task Force has just 5th Edition Pdf 4th Edition Fmea Manual Design Fmea And .
Here are three real examples. A cross-functional team was formed that included individuals from outside of the assembly department, although all were familiar with assembly to some extent. While the manager was a team member, his role was to keep notes, not to lead the team. After a brief FMEA training session, the team decided to collect data and information from other operators that were not on the team.
With that information, they were able to complete the FMEA in four two-hour sessions. The team continues to work to further reduce the defects. When an organization achieves ISO certification, that organization has developed, instituted, and uses systems capable of controlling processes that determine the acceptability of its product or services. ISO , which combined the earlier standards of ISO , , and , defines the requirements of a comprehensive quality management system. A product failure occurs when the product does not function as it should or when it malfunctions in some way.
Even the simplest products have many opportunities for failure. Failures are not limited to problems with the product. Because failures also can occur when the user makes a mistake, those types of failures should also be included in the FMEA.
Anything that can be done to ensure the product works correctly, regardless of how the user operates it, will move the product closer to percent total customer satisfaction. Ways in which a product or process can fail are called failure modes.
Each failure mode has a potential effect, and some effects are more likely to occur than others. The FMEA process is a way to identify the failures, effects, and risks within a process or product, and then eliminate or reduce them.
The risk priority number which will range from 1 to 1, for each failure mode is used to rank the need for corrective actions to eliminate or reduce the potential failure modes. Those failure modes with the highest RPNs should be attended to first, although special attention should be given when the severity ranking is high 9 or 10 regardless of the RPN.
Once corrective action has been taken, a new RPN for the failure is determined by reevaluating the severity, occurrence, and detection rankings.
The purpose for an FMEA team is to bring a variety of perspectives and experiences to the project. In fact, it would be inappropriate to establish a permanent FMEA team because the composition of the team is dictated by the specific task or objective.
In cases where several FMEAs are needed to cover one process or product, it is good practice to have some overlap of members between the teams, but there also should be some members who serve on only one or two of the teams to ensure a fresh perspective of the potential problems and solutions. Each area for example, manufacturing, engineering, maintenance, materials, and technical service should be represented on the team.
The customer of the process, whether internal or external to the organization, can add another unique perspective as well and should be considered for team membership. Those who are most familiar with it will have valuable insights, but may overlook some of the most obvious potential problems. Those who are less familiar with the process or product will bring unbiased, objective ideas into the FMEA process. Be aware that those with an emotional investment in the process or product may be overly sensitive during the critiquing process and may become defensive.
Arrangements should be made for someone to be responsible for taking meeting minutes and maintaining the FMEA records.
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A person with expertise in the process for example, the design engineer in a design FMEA or the process engineer in a process FMEA can bring tremendous insight to the team and can help speed the process.
In many ways he or she can be a real asset to the team. On the other hand, a process expert can also slow down the FMEA process. This is especially difficult for the process expert.
Most likely he or she has a huge investment in the process or product, in terms of both time and personal integrity.
A team leader or facilitator who is well versed in the FMEA process can easily guide the team through the process as they are actually performing the FMEA. This means that there is not a need for extensive classroom training. Instead, the FMEA team can be immediately productive working on a real FMEA project and at the same time benefit from the most powerful form of training—experience.
Knowledge of consensus-building techniques, team project documentation, and idea-generating techniques such as brainstorming are all necessary for FMEA team members.
Management is responsible for defining the boundaries of freedom. Some of the boundaries of freedom can be standing guidelines for all FMEA teams. For example, a standard procedure can be established to define the process that teams must follow if they need to go beyond the normal boundaries, and this procedure can apply to all FMEA teams.
The same holds true for the process that the team should use to communicate the FMEA results to others in the organization. While management is responsible for defining the boundaries of freedom, the FMEA team members have equal responsibility in making sure these boundaries are defined before the project gets under way.
If the team members do not know what the boundaries are or if they are unclear about any of the boundaries, they should get clarification before proceeding with the FMEA. This will help the team avoid problems and conflicts later in the process.
This definition usually comes from the leader of the function responsible for the FMEA. If the FMEA is focused on the design of a product, the head of the design function should clearly define the scope of the project. For a process FMEA, the leader of the manufacturing or manufacturing-engineering function would most likely define the scope. A specific and clear definition of the process or product to be studied should be written and understood by everyone on the team.
Team members should have an opportunity to clarify their understanding of the scope, if necessary, and those clarifications should be documented. This will help prevent the team from focusing on the wrong aspect of the product or process during the FMEA. The FMEA will not include any parts of this coffeemaker that are common to other coffeemakers in our product line, such as the electronic clock, the electrical cord and wiring into the coffeemaker, and the gold cone coffee filter.
A specific and clear definition is even more important with process FMEAs because they can encompass so many different aspects of the process manufacturing chain, from the raw materials to components, to the actual manufacturing and assembly, to the shipping, and everything in between.
While each part of the chain plays an important role in the quality of a product, it may help to use a narrow definition of the process to ensure that the FMEA project is completed in a timely manner.
Because large processes may be difficult to work on in their entirety, break them into subprocesses when possible and attend to them one at a time, or have several teams working at the same time on different subprocesses. What is the scope of the FMEA? For example, an organization may decide that any RPN above creates an unacceptable risk. This decision sets the cutoff RPN at Take Action to Eliminate or Reduce the High-Risk Failure Modes Using an organized problem-solving process, identify and implement actions to eliminate or reduce the high-risk failure modes.
Ideally, the failure modes should be eliminated completely. For example, gasoline companies, car manufacturers, and pump manufacturers worked together during the phase-out of leaded fuel to eliminate the potential failure mode of putting leaded fuel into a car that runs on unleaded fuel. This was accomplished by making the gas tank opening too small for the leaded gas nozzle.
When a failure mode has been eliminated completely, the new risk priority number approaches zero because the occurrence ranking becomes one.
While elimination of failure modes altogether is ideal, it may not be achievable in all cases. When this happens, it helps to refer back to the severity, occurrence, and detection rankings that the team assigned to each item.
Think of ways to reduce the rankings on one, two, or all three of the scales. Often, the easiest approach for making a process or product improvement is to increase the detectability of the failure, thus lowering the detection ranking.
For example, a coffeemaker might have a tone that sounds every ten minutes to remind you that it is turned on and that you need to turn it off before you leave the house, or a computer manufacturer may include a piece of software that notifies the user that there is low disk space.
However, these are Band-Aid approaches that often are costly and do not actually improve the quality of the product. Increasing failure detectability will simply make it easier to detect failures once they occur. Reducing the severity is important, especially in situations that can lead to injuries. For example, a company that manufactures weed wackers might limit the speed of the machine, reducing the severity of a potential personal injury.
However, the richest opportunity for improvement lies in reducing the likelihood of occurrence of the failure. After all, if it is highly unlikely that a failure will occur, there is less need for detection measures. Step Calculate the Resulting RPN as the Failure Modes Are Reduced Once action has been taken to improve the product or process, new rankings for severity, occurrence, and detection should be determined, and a resulting RPN calculated.
For the failure modes where action was taken, there should be a significant reduction in the RPN. If not, that means action did not reduce the severity, likelihood of occurrence, or detectability.
In addition, the total RPNs of the before-and-after product or process can be compared and contrasted. It is up to the FMEA team and the company to decide on how far the team should go with improvements.
There will always be the potential for failure modes to occur. The question the company must ask is how much relative risk the team is willing to take. That answer will depend on the industry and the seriousness of failure. For example, in the nuclear industry, there is little margin for error; they cannot risk a disaster occurring.
In other industries, it may be acceptable to take higher risks. The company developed a new extinguisher for home use. It wanted to make sure the extinguisher would be effective and would not cause any problems when used. The consequences of a faulty extinguisher could be life-threatening.
A team of five employees was formed to work through the FMEA process. The team included a design engineer who helped develop the extinguisher, the second-shift manufacturing supervisor, the first-shift quality technician, the downloading manager, and the sales and marketing manager. The deadline for project completion was April 15, at which time another team would be formed to conduct a process FMEA. Case Study Step 1: Review the Process All team members were given a blueprint of the fire extinguisher to review.
The design engineer brought a prototype extinguisher to the first meeting and demonstrated how it worked. He also handed out a product specification sheet. For example, the product manager demonstrated how the extinguisher worked, highlighting the differences in operation between the new and existing models. One participant asked if this extinguisher would work the same for left- and right-handed people as do the existing models.
Another wanted to know the benefits of the rounder shape of the canister. The most logical breakdown was into the key components of the extinguisher: The chemical agent in the extinguisher was excluded because another team had included it in an FMEA about six months earlier. The team then brainstormed all of the potential failures for each of those components.
For example, with the hose, potential failures were cracks, holes, and blockages. With the canister, one potential failure was that the canister could be dented, and another was that the label might not be properly glued.
While there was some disagreement about the likelihood that a certain effect would occur, the team agreed to include all possible effects. Members reasoned that if it was highly unlikely that the failure and effect would occur, then the item would probably get a low RPN anyway. The team listed each potential effect next to the failure.
If members felt that several different effects were possible, and anticipated that each might have a different ranking in at least one of the three ranking categories, they listed them in a separate row. Shane T. Tyler J. Chase L. March 5 K. Are all affected areas represented? Are different levels and types of knowledge represented on the team? NO Boundaries of Freedom 5. April Do team members have specific time constraints? Review with steering committee 9. In most cases, members agreed on the severity ranking, although in a couple of instances they had heated discussions before reaching consensus.
Each member voted the score they felt the item should get, and the final ranking was an average of all of the votes. Assign an Occurrence Ranking for Each Failure Mode The team began this step by collecting data on failures with similar fire extinguishers. For the failure modes where no data existed, the team identified the potential causes of failure associated with each failure mode.
Case Study Step 6: Case Study Step 7: Calculate the Risk Priority Number for Each Failure Mode The RPN was calculated for each potential failure mode by multiplying the severity times the occurrence times the detection ranking. The team noted that there were significant differences among the rankings, which made it easy to distinguish between the items that required action and those that could be left as is.
The highest score was points, and the lowest was 48 points. The team decided it would work on any item that had an RPN of or higher. Two hundred was set as the cutoff point because it encompassed over half of all of the potential failure modes. The team rationalized that an improvement in more than half of the failure modes would be a significant step in the right direction. With the criteria of an RPN of or higher, there were eight items they would need to attend to.
Case Study Step 9: Case Study Step Calculate the Resulting RPN as the Failure Modes Are Reduced or Eliminated After completing the corrective action, the team met, and all members responsible for an action item gave a report. All commitments were met, and the team was able to conduct its reevaluation FMEA at that same meeting. The eight areas addressed were at or below the target of points.
FMEAs provide a structure and a common language that can be used by teams in manufacturing and service, profit and not-for-profit, private, public, or governmental organizations. FMEA is not just a tool for the manufacturing or engineering department. It can be used to improve support processes, not just manufacturing processes or product design. A discussion of some of the support processes where FMEA might be useful follows. Safety FMEAs were first developed as a tool to identify and correct safety hazards.
The FMEA process was developed to anticipate and eliminate safety problems before they occurred. Consequently, FMEAs can be used to improve the safety of the process of manufacturing a product as well as to improve the safety performance of the product itself. Manufacturing safety FMEAs should be conducted by a team of people who operate the equipment, along with others who are not involved in operating the equipment.
In many cases, it is not sufficient that product instructions spell out safe operating procedures; safety provisions must be built in to the products. It is helpful to involve consumers or eventual users of the product in such an FMEA. They should be asked to use the product, and other members of the FMEA team should observe how it is used. It is not unusual for a product to be incorrectly used or to be used for an unintended purpose.
If these possibilities can be uncovered during an FMEA, safeguards can be built in to the product design. For example, before extending substantial credit to a potential customer with a shaky credit history, an FMEA that studies the things that could go wrong with customer credit and how credit failures would affect the company would provide a structure for a credit plan that will reduce financial risk. Software Design The effects of software are all around us.
Practically everything that we do is governed by software. Software quality assurance is critical in many of these instances. For example, computer systems and the software that drives them are used in air transportation, medicine, and banking, to name a few applications. From the simplest local area network LAN to multi-million-dollar telecommunications systems, use of FMEAs can help make both the design and installation of information systems more robust.
Some promotional campaigns are wildly successful, while others are financial busts. An FMEA conducted prior to an advertising or marketing launch can help businesses avoid costly and sometimes embarrassing mistakes. An FMEA can be used to identify offensive or misleading advertising copy. It can also be used to preplan reaction and response to potentially damaging product recalls or disasters. Human Resources With organizational restructuring downsizing, right-sizing , the human resources field is faced with developing and executing plans for new organizational structures that are significantly different from the classic pyramid structures we are all familiar with.
Changes on paper that appear to be workable can turn into disasters. An FMEA can be used as a bridge between the plan and the actual restructuring.
FMEA 4th Edition
FMEAs force a structured analysis of problems and glitches that might happen. Plans can be designed to address the potential problems and crises can be avoided, saving time and money while improving morale. downloading Prior to downloading a major piece of equipment, an FMEA can be conducted to anticipate problems with different download options.
This information can be used to improve downloading decisions as well as to develop installation plans once the equipment is downloadd. Human resources An HR department led an FMEA that involved senior managers from all departments during an organizational restructuring.
downloading Working with the process-engineering department, a downloading group used an FMEA to select a new piece of manufacturing equipment. Appendix 1 Creating a Process Flowchart Flowcharts are to manufacturing processes what road maps are to drivers. They provide a detailed view of the process, and increase understanding of how the process flows. With a process flowchart, teams can identify repetitive steps, bottlenecks, and inefficiencies in the process.
The best way to create a flowchart is to walk through the process as if you were the thing being processed or created. The process steps should be followed sequentially, and notes should be taken during the walk-through.
Aiag Fmea 4th Edition
Avoid shortcuts while going through the process, as you may miss critical steps. Once the walk-through is complete, each step should be listed on a self-stick note. It helps to have several people do this, as each will contribute ideas that others missed.
The steps should then be grouped and organized according to their order in the process. For complicated processes with several steps and substeps, it helps to create a top-down flowchart, where each of the major steps in the process are listed in order of flow across the top of the chart, and the substeps are listed underneath each major step see Figures A1.
Once the steps are identified and put in order, symbols are assigned to each step. At this point, missed steps become more obvious and can be added as needed. With all the steps in place, arrows connecting the symbols are added to show the direction of the process flow. Activity Steps—Shows activities in the process. There can be more than one arrow coming in but only one arrow going out. Write a brief description of the activity in the rectangle.
Decision Points—Shows decision points in the process. There must be at least two arrows out of a diamond, and they must be labeled with answers to the questions written in the diamond.
Use letters beginning with A and work through the alphabet. The detailed substeps are outlined below each major step. Figure A1. As a final step, the flowchart should be tested by walking through the process again, this time using the chart as a guide.
Corrections should be made, and a process should be established to review and revise the flowchart periodically to make sure it is kept current.
No Process changed? Flowchart accurate? There are many different ways to brainstorm, depending on the objectives of the session. A round-robin approach works best for FMEAs, because it allows each person the opportunity to express his or her ideas, while keeping the creativity level high.
The round-robin approach to brainstorming allows each person to contribute one idea each time it is his or her turn. Participants should come to the brainstorming meeting with a list of ideas to contribute to the process.
To encourage creative ideas, no idea should be critiqued or commented on when offered. Each idea should be listed and numbered, exactly as offered, on a flip chart.
Expect to generate at least fifty to sixty ideas in a thirty-minute brainstorming session. It helps to review the rules of round-robin-style brainstorming with the group before the session begins. Brainstorming Rules 1. Do not comment on, judge, or critique ideas as offered.
Encourage creative and offbeat ideas. A large number of ideas is the goal. Evaluate ideas later. When the brainstorming session is over, the ideas should be reviewed, similar ideas combined, and ideas that do not seem to fit eliminated. Ideally, everyone on the FMEA team would agree on the severity, occurrence, and detection rankings.
Disagreements without a structured process to address and resolve them can waste a lot of time and energy. The team should agree, in advance, on a process to handle disagreements. Outlined below are some methods to help reach consensus. Linking their argument to the predefined ranking scale will help strengthen their position. When the presentations are complete, team members should cast their votes for what they feel the ranking should be.
The mean arithmetic average ranking should be calculated and used as a reference point for the team to arrive at a consensus score. The voting process is a consensus-reaching tool, but it alone cannot ensure that the entire team supports the ranking. If the voting process does not help the group arrive at consensus, there are a few other exercises the team can work through to reach agreement.
Get the Process Expert Involved If the process expert is not on your team, you might want to invite him or her to a meeting to review the FMEA rankings and give an opinion about how the item in question should be rated. The expert should not have the final say in the ranking, but rather should provide the team with information that perhaps they did not know or were not aware of. The team has the final say. Defer to One of the Team Members Your team could assign one member of the team to make the final decision if there is a person on the team with a lot of expertise on the product or process.
The problem with this approach is that there is a chance some team members might not agree with the ranking and, in turn, will have a difficult time supporting the FMEA from this point on. Rank Failures and Effects within a Ranking Category List each failure and effect on a self-stick note.
Do not worry about the actual score of the ranking in question. Instead, put the failures in order from the highest to the lowest according to the scale in question. For example, if the scale in question is severity and the team is unable to reach agreement on the ranking of two or more of the failure modes, put each of the failure modes on a self-stick note.
The Basics of FMEA
At this point, you should not be concerned with the numerical ranking for the failure modes. Once the failures are in order, indicate the rankings for any of the failure modes that the team has been able to agree upon.
By thinking of the failures relative to each other, rather than in terms of an absolute scale, you may be able to agree on the rankings for the failure modes in dispute. The difference could put the item below the cutoff point, when it should be above the cutoff point. This would mean that a relatively high-risk failure would not be eliminated or reduced. Therefore, it is risky to assign rankings arbitrarily just to move the FMEA process along.
Sometimes the best way to reach consensus on a particularly sticky issue is to talk it out.
Use the Higher Ranking If the team just cannot reach consensus, the team might elect to use the higher ranking. The loss with this approach is the time taken away from working on another item. There could be tremendous gains to using this approach and operating on the safe side. Product creates major hazardous environmental disposal problem. Use of product leads to poor housekeeping.
Design protocols are formalized. Design reviews held to ensure compliance to design rules. Checklist used to ensure design rules are followed. The number of components has been minimized. Only standard components have been used. Ergonomic assembly techniques have been incorporated. Asymmetrical features used to mistake-proof assembly.
Partial functionality of prototype tested before release. Full Alpha tests conducted; no Beta testing. Untested computer model used to simulate product performance.
Extensive product recall.
Unscheduled engine removal. Premature unscheduled component replacement. Oil leak but system still operational. Air-conditioning system not operating properly. Interior panel rattles. Variation in seat colors. Door plugs missing. Scratch on interior of housing. Loss of customer due to late delivery.
Entire lot of top-level assembly product scrapped. Full assembly line or bottleneck operation down more than 1 week. Rework full lot of top-level assemblies. Scrap full lot of sub-level assemblies. Technical engineering resources required to get line operational. Equipment down for more than 1 hour. Engineering disposition. Large hazardous material spill or release.
OSHA recordable injury. Personnel exposure above PEL. Moderate hazardous material spill or release. Fail internal ISO audit. Spill of nonhazardous material. Minor nonhazardous coolant spill.
Poor housekeeping. Appendix 5 Process Improvement Techniques Organizations have a wide variety of approaches to improvement available to them once an improvement opportunity has been identified. The improvement opportunities identified through an FMEA are no exception.
Some effective techniques for following through on identified opportunities are described briefly below. Mistake Proofing Mistake-proofing techniques, when implemented properly, make it virtually impossible to have a failure. An excellent example of mistake-proofing is a car that will not start unless the clutch pedal is depressed.
This prevents the car from lurching forward when it is started. Before this was mistake-proofed, a driver could try to start the car while it was in gear, causing it to jump forward into other cars, objects, and even people. Mistake-proofing techniques include ways to make it impossible to make mistakes in both the manufacture and use of products. Limit switches, electric eyes, bar coding, and counting techniques can all be used to mistake-proof processes and products.
Design of experiments is effective in both continuous and discrete processes. DOE can be used in the product development stage as well.
There are many types of DOEs. Full factorials, fractional factorials, response surface methodology, and evolutionary operations EVOP are some. Perhaps the most powerful type of DOE is the family of extreme fractional factorial designs called screening experiments. Using a screening experiment, it is possible to vary several process variables at the same time and statistically determine which variables or combination of variables have the greatest impact on the process outcomes.
Once these key variables are known, the FMEA team can focus its efforts just on these variables, saving time, effort, and money. Statistical Process Control Statistical process control SPC , another statistical technique, is a tool that can be used to monitor processes to make sure they have not changed or to compare the output of a process to the specification.
The FMEA team can use control charts to get a real-time view of the process. When a failure occurs in the process, the control charts will signal a change. By quickly reacting to the signal, the team can work to find the root cause of the failure before the trail gets cold. Once the root cause is found, mistake-proofing can be used to eliminate the failure mode, taking the resulting RPN to essentially zero.
Basic well-known improvement tools include brainstorming, flowcharting, data collection and analysis, voting and ranking, Pareto analysis, cause-and-effect analysis, and action planning.
The requirements of Section 7. The standard focuses on error prevention rather than detection and specifies the use of FMEAs as part of this effort. Special characteristics can include product characteristics and process parameters. The product design output shall include - design FMEA, reliability results, - product special characteristics and specifications, - product error-proofing, as appropriate, - product definition including drawings or mathematically based data, - product design reviews results, and - diagnostic guidelines where applicable.
Section 7. References to FMEAs follow: The control plan shall - list the controls used for the manufacturing process control, - include methods for monitoring of control exercised over special characteristics see 7.
Control plans shall be reviewed and updated when any change occurs affecting product, manufacturing process, measurement, logistics, supply sources or FMEA see 7. For more information contact AIAG www. Alternative worksheets are included as Table A7. Automotive Industry Action Group. Design of experiments DOE: Series of statistical techniques used to introduce controlled change into a process and to study the effect of the change on the process outcomes.
Failure Mode and Effect Analysis. A systematic, structured approach to process improvement in the design and process development stage. International quality standards for product design, manufacture, and distribution.
Making the process so robust that it cannot fail; also called error-proofing.
FMEA ranking scale that defines the frequency of a failure mode. Resulting RPN: Risk priority number of a failure mode and its corresponding effects after improvements. Risk priority number RPN: Risk priority number of a failure mode and its effects before improvement. FMEA ranking scale that defines the seriousness and severity of the effect of the failure, should it occur. Statistical process control SPC: Statistical technique used to monitor processes, usually involving the use of control charts.
Total RPN: Calculated by adding together all of the risk priority numbers for an FMEA. This number alone is meaningless, but can serve as a gauge to compare the revised total RPN once the recommended actions have been instituted. The Basics of Chemistry. Read more.
The Basics of Economics.Do team members have specific time constraints? Step 7 Calculate the risk priority number for each effect. Part 5: What are the product material requirements and constraints? For a product FMEA, they should physically see the product or a prototype of it. Anything that can be done to ensure the product works correctly, regardless of how the user operates it, will move the product closer to percent total customer satisfaction.