Failure Mode and Effects Analysis (#FMEA) ? Quality control tools, Quality Assurance FMEA 4th Edition #FMEAinquality #7QCtools
नई खबर
#FMEA4thEdition
Identify Potential Causes
Potential cause of failure is defined as an indication of how the failure could occur, described in terms of something that can be corrected or can be controlled. Potential cause of failure may be an indication of a design weakness, the consequence of which is the failure mode.
There is a direct relation between a cause and its resultant failure mode (i.e., if the cause occurs, then the failure mode occurs). Identifying the root cause(s) of the failure mode, in sufficient detail, enables the identification of appropriate controls and action plans. A separate potential cause analysis is performed for each cause if there are multiplecauses.
Identify Controls
Controls are those activities that prevent or detect the cause of the failure or failure mode. In developing controls it is important to identify what is going wrong, why, and how to prevent or detect it. Controls are applicable to product design or manufacturing processes. Controls focused on prevention will provide the greatestreturn.
Identifying and Assessing Risk
One of the important steps in the FMEA process is the assessment of risk. This is evaluated in three ways, severity, occurrence, and detection:
Severity is an assessment of the level of impact of a failure on the customer.
Occurrence is how often the cause of a failure may occur.
Detection is an assessment of how well the product or process controls detect the cause of the failure or the failure mode.
Recommended Actions and Results
Organizations need to understand their customer requirements for riskassessment.
The intent of recommended actions is to reduce overall risk and likelihood that the failure mode will occur. The recommended actions address reduction of the severity, occurrence and detection.
The following can be used to assure that the appropriate actions are taken, including but not limited to:
1. Ensuring design requirements including reliability are achieved,
2. Reviewing engineering drawings andspecifications,
3. Confirming incorporation in assembly/manufacturing processes,and,
4. Reviewing related FMEAs, control plans and operations instructions.
Responsibility and timing to complete the recommended actions should be recorded.
Once actions are completed and results captured, the updated ratings for severity, occurrence and detection should also be recorded.
Chapter II Strategy, Planning, Implementation
Management Responsibility
Management owns the FMEA process. Management has the ultimate responsibility of selecting and applying resources and ensuring an effective risk management process including timing.
Management responsibility also includes providing direct support to the team through on-going reviews, eliminating roadblocks, and incorporating lessonslearned.
#FMEA4thEdition
Failure Mode and Effects Analysis (FMEA) ? Why,When and How to Perform FMEA
The FMEA 4th Edition is a reference manual to be used by suppliers to Chrysler LLC, Ford Motor Company, and General Motors Corporation as a guide to assist them in the development of both Design and Process FMEAs. The manual does not define requirements; it is intended to clarify questions concerning the technical development of FMEAs. This manual is aligned with SAE J1739.
#FMEAinquality
#TypesofFMEA
#FMEAinquality
#TypesofFMEA
Summary of Changes in the 4th edition FMEA Reference Manual:-
The DFMEA and PFMEA methods described in the 4th edition FMEA Reference Manual include those associated with design at the system, subsystem, interface, and component level and the process at manufacturing and assembly operations.
The DFMEA and PFMEA methods described in the 4th edition FMEA Reference Manual include those associated with design at the system, subsystem, interface, and component level and the process at manufacturing and assembly operations.
General Changes:-
1.The formatting used in the 4th edition is intended to provide easierreading.
o An index isincluded.
o Icons are used to indicate key paragraphs and visual cues areused.
2. Additional examples and verbiage have been provided to improve the utility ofthe manual and to provide a closer tie into the FMEA process as itdevelops.
3. Reinforcement of the need for management support, interest, and review of the FMEA process andresults.
4. Define and strengthen the understanding of the linkage between DFMEA and PFMEA as well as defining the linkages to othertools.
5. Improvements to the Severity, Occurrence, Detection ranking tables so that they are more meaningful to real world analysis andusage.
6. Alternative methods are introduced that are currently being applied inindustry.
o Additional appendices which have example forms and special case application of FMEA.
o The focus on the “standard form” has been replaced with several options that represent the current application of FMEA inindustry.
7.The suggestion that RPN not be used as the primary means for assessing risk. The need for improvement has been revised including an additional method, and the use of thresholds on RPN is clarified as a practice that is notrecommended.
FMEAExplained:-
FMEAs are an integral part of managing risk and supporting continual improvement. Consequently, FMEA becomes a key part of Product and Process development. The Advanced Product Quality Planning (APQP) process identifies five general areas of focus in this development process:
1. Plan and DefineProgram
2. Product Design andDevelopment
3. Process Design andDevelopment
4. Product and ProcessValidation
5. Feedback, Assessment and CorrectiveAction
The APQP Reference manual shows DFMEAs as an activity in the Product Design and Development section of the timing chart and PFMEAs in the Process Planning and Development section. The development of either DFMEA or PFMEA is a process that helps to guide the teams in developing product and process designs that meet expectations.
The FMEA analysis should not be considered a single event, but a long-term commitment that complements the product and process development to ensure potential failures are evaluated and actions are taken to reduce their risk.
One key aspect of continual improvement is the retention of knowledge from past learning which often is captured in FMEAs. It is advisable for organizations to capitalize on prior analyses of similar product and process designs for use as the starting point for the next program and/orapplication.
The language used in FMEAs should be as specific as possible when describing an item (for example, failure mode, or cause) and not extend or extrapolate beyond the team’s level of understanding as to what the failure effects may be.
Clear statements, concise terminology and focus on the actual effects are key to the effective identification and mitigation of risk issues.
Define the Scope:-
Scope establishes the boundary of the FMEA analysis. It defines what is included and excluded, determined based on the type of FMEA being developed, i.e., system, subsystem, or component. Before the FMEA can begin, a clear understanding of what is to be evaluated must be determined. What to exclude can be just as important as what to include in the analysis. The scope needs to be established at the start of the process to assure consistent direction and focus.
The following may assist the team in defining the scope of the FMEA:
1. FunctionModel
2. Block (Boundary)diagrams
3. Parameter (P)diagrams
4. Interfacediagrams
5. Process flowdiagrams
6. Interrelationshipmatrices
7. Schematics
8. Bill of Materials(BOM)
System FMEA
A system FMEA is made up of various subsystems. Examples of systems include: Chassis System, Powertrain System, or Interior System, etc. The focus of the System FMEA is to address all interfaces and interactions among systems, subsystems, the environment and the customer.
Subsystem FMEA
A Subsystem FMEA is a subset of a system FMEA. An example of a subsystem is the front suspension subsystem, which is a subset of the chassis system. The focus of the Subsystem FMEA is to address all interfaces and interactions among the subsystem components and interactions with other subsystems or systems.
Component FMEA
A Component FMEA is a subset of a subsystem FMEA. For example, a brake pad is a component of the brake assembly, which is a subsystem of the chassis system.
NOTE: Any subsequent adjustments to the scope may require a modification of the team structure and membership.
Indentify Functions, Requirements, and Specifications
Identify and understand the functions, requirements and specifications relevant to the defined scope. The purpose of this activity is to clarify the item design intent or process purpose. This assists in the determination of the potential failure mode for each attribute or aspect of the function.
Identify Potential Failure Modes
Failure mode is defined as the way or manner in which a product or process could fail to meet design intent or process requirements. The assumption is made that the failure could occur but may not necessarily occur. A concise and understandable failure definition is important since it properly focuses the analysis. Potential failure modes should be described in technical terms and not as a symptom necessarily noticeable by the customer. A large number of failure modes identified for a single requirement may indicate that the defined requirement is notconcise.
Identify Potential Effects
Potential effects of failure are defined as the effects of the failure mode as perceived by the customer. The effects or impact of the failure are described in terms of what the customer might notice or experience. The customer may be an internal customer as well as the EndUser.
Determining potential effects includes the analysis of the consequences of the failures and the severity or seriousness of those consequences.
1.The formatting used in the 4th edition is intended to provide easierreading.
o An index isincluded.
o Icons are used to indicate key paragraphs and visual cues areused.
2. Additional examples and verbiage have been provided to improve the utility ofthe manual and to provide a closer tie into the FMEA process as itdevelops.
3. Reinforcement of the need for management support, interest, and review of the FMEA process andresults.
4. Define and strengthen the understanding of the linkage between DFMEA and PFMEA as well as defining the linkages to othertools.
5. Improvements to the Severity, Occurrence, Detection ranking tables so that they are more meaningful to real world analysis andusage.
6. Alternative methods are introduced that are currently being applied inindustry.
o Additional appendices which have example forms and special case application of FMEA.
o The focus on the “standard form” has been replaced with several options that represent the current application of FMEA inindustry.
7.The suggestion that RPN not be used as the primary means for assessing risk. The need for improvement has been revised including an additional method, and the use of thresholds on RPN is clarified as a practice that is notrecommended.
FMEAExplained:-
FMEAs are an integral part of managing risk and supporting continual improvement. Consequently, FMEA becomes a key part of Product and Process development. The Advanced Product Quality Planning (APQP) process identifies five general areas of focus in this development process:
1. Plan and DefineProgram
2. Product Design andDevelopment
3. Process Design andDevelopment
4. Product and ProcessValidation
5. Feedback, Assessment and CorrectiveAction
The APQP Reference manual shows DFMEAs as an activity in the Product Design and Development section of the timing chart and PFMEAs in the Process Planning and Development section. The development of either DFMEA or PFMEA is a process that helps to guide the teams in developing product and process designs that meet expectations.
The FMEA analysis should not be considered a single event, but a long-term commitment that complements the product and process development to ensure potential failures are evaluated and actions are taken to reduce their risk.
One key aspect of continual improvement is the retention of knowledge from past learning which often is captured in FMEAs. It is advisable for organizations to capitalize on prior analyses of similar product and process designs for use as the starting point for the next program and/orapplication.
The language used in FMEAs should be as specific as possible when describing an item (for example, failure mode, or cause) and not extend or extrapolate beyond the team’s level of understanding as to what the failure effects may be.
Clear statements, concise terminology and focus on the actual effects are key to the effective identification and mitigation of risk issues.
Define the Scope:-
Scope establishes the boundary of the FMEA analysis. It defines what is included and excluded, determined based on the type of FMEA being developed, i.e., system, subsystem, or component. Before the FMEA can begin, a clear understanding of what is to be evaluated must be determined. What to exclude can be just as important as what to include in the analysis. The scope needs to be established at the start of the process to assure consistent direction and focus.
The following may assist the team in defining the scope of the FMEA:
1. FunctionModel
2. Block (Boundary)diagrams
3. Parameter (P)diagrams
4. Interfacediagrams
5. Process flowdiagrams
6. Interrelationshipmatrices
7. Schematics
8. Bill of Materials(BOM)
System FMEA
A system FMEA is made up of various subsystems. Examples of systems include: Chassis System, Powertrain System, or Interior System, etc. The focus of the System FMEA is to address all interfaces and interactions among systems, subsystems, the environment and the customer.
Subsystem FMEA
A Subsystem FMEA is a subset of a system FMEA. An example of a subsystem is the front suspension subsystem, which is a subset of the chassis system. The focus of the Subsystem FMEA is to address all interfaces and interactions among the subsystem components and interactions with other subsystems or systems.
Component FMEA
A Component FMEA is a subset of a subsystem FMEA. For example, a brake pad is a component of the brake assembly, which is a subsystem of the chassis system.
NOTE: Any subsequent adjustments to the scope may require a modification of the team structure and membership.
Indentify Functions, Requirements, and Specifications
Identify and understand the functions, requirements and specifications relevant to the defined scope. The purpose of this activity is to clarify the item design intent or process purpose. This assists in the determination of the potential failure mode for each attribute or aspect of the function.
Identify Potential Failure Modes
Failure mode is defined as the way or manner in which a product or process could fail to meet design intent or process requirements. The assumption is made that the failure could occur but may not necessarily occur. A concise and understandable failure definition is important since it properly focuses the analysis. Potential failure modes should be described in technical terms and not as a symptom necessarily noticeable by the customer. A large number of failure modes identified for a single requirement may indicate that the defined requirement is notconcise.
Identify Potential Effects
Potential effects of failure are defined as the effects of the failure mode as perceived by the customer. The effects or impact of the failure are described in terms of what the customer might notice or experience. The customer may be an internal customer as well as the EndUser.
Determining potential effects includes the analysis of the consequences of the failures and the severity or seriousness of those consequences.
Potential cause of failure is defined as an indication of how the failure could occur, described in terms of something that can be corrected or can be controlled. Potential cause of failure may be an indication of a design weakness, the consequence of which is the failure mode.
There is a direct relation between a cause and its resultant failure mode (i.e., if the cause occurs, then the failure mode occurs). Identifying the root cause(s) of the failure mode, in sufficient detail, enables the identification of appropriate controls and action plans. A separate potential cause analysis is performed for each cause if there are multiplecauses.
Identify Controls
Controls are those activities that prevent or detect the cause of the failure or failure mode. In developing controls it is important to identify what is going wrong, why, and how to prevent or detect it. Controls are applicable to product design or manufacturing processes. Controls focused on prevention will provide the greatestreturn.
Identifying and Assessing Risk
One of the important steps in the FMEA process is the assessment of risk. This is evaluated in three ways, severity, occurrence, and detection:
Severity is an assessment of the level of impact of a failure on the customer.
Occurrence is how often the cause of a failure may occur.
Detection is an assessment of how well the product or process controls detect the cause of the failure or the failure mode.
Recommended Actions and Results
Organizations need to understand their customer requirements for riskassessment.
The intent of recommended actions is to reduce overall risk and likelihood that the failure mode will occur. The recommended actions address reduction of the severity, occurrence and detection.
The following can be used to assure that the appropriate actions are taken, including but not limited to:
1. Ensuring design requirements including reliability are achieved,
2. Reviewing engineering drawings andspecifications,
3. Confirming incorporation in assembly/manufacturing processes,and,
4. Reviewing related FMEAs, control plans and operations instructions.
Responsibility and timing to complete the recommended actions should be recorded.
Once actions are completed and results captured, the updated ratings for severity, occurrence and detection should also be recorded.
Chapter II Strategy, Planning, Implementation
Management Responsibility
Management owns the FMEA process. Management has the ultimate responsibility of selecting and applying resources and ensuring an effective risk management process including timing.
Management responsibility also includes providing direct support to the team through on-going reviews, eliminating roadblocks, and incorporating lessonslearned.
Comments
Post a Comment