FMEA Flashcards
What are the key issues with FMEA? (9)
- it should be management led and needs a strategy to be used
- training is required
- it can be subjective
- it is performed too late in the produce development process
- input from suppliers and customers is critical
- Needs to be reviewed on a regular basis
- A team-based application is very useful.
- Design FMEAs should be supported with failure data wherever possible.
- They can help to build up a knowledge base for product families.
What are the 7 factors are assessed in FMEA? (P3COSD)
1) Potential failure mode - how could the components fail to meet each aspect of the spec
2) Effects of failure - what would the consequence be
3) Cause of failure - why would it fail in the way suggested by the potential failure
4) Current controls - what can be done to reduce chance of failure
5) Occurrence - probability of failure will take place
6) Severity - effect of failure on the user/environment
7) Detectability - probability fault will go undetected before failure
What is FMEA?
FEMA is a systematic element by element assessment ot highlight the effects of a component, product, process or system failure to meet all the requirements of a customer specification, including safety
What is the house of quality?
House of quality diagram aids in determining how a product is living up to customer needs. Used for defining the relationship between customers desired and the firms/product capability.
What are the benefits of FMEA? (6)
Highlight the need for design improvement
• Highlight priority areas for focusing limited resources
• Highlight the need for different levels of inspection, e.g. statistical process control
(SPC), 100% inspection, no inspection
• Identify parts which have redundant function
• Prioritise those suppliers to which attention needs to be given
• Provide a basis for measures of performance.
Through effective use, what can FMEA reduce? (5)
Customer complaints
• Late design changes
• Defects during manufacture and assembly
• Failures in the field
• Failure costs (rework, warranty claims).
How does FMEA relate to systems?
In a system FMEA the focus is on failures in
system function and their potential causes, including system safety and system integration,
system and sub-system interfaces and interactions, single-point failures (where a single
component failure can result in complete failure of the entire system) and system functions
and relationships that are unique to the system as a whole (i.e., do not exist at lower levels)
that could cause the overall system not to work as intended.
How does FMEA apply to processes?
In a process
FMEA, analysis is at the manufacturing/assembly process level. The focus is on
manufacturing related deficiencies in manufacturing and assembly operations, transport,
storage, and so on with emphasis on improving the manufacturing process, and ensuring the
product is built to design requirements in a safe manner, with minimal downtime, scrap and
rework.
How does FMEA apply to a design?
In a design FMEA, analysis is
at the subsystem level (made up of various components) or component level, and focus is
on product design-related deficiencies, with emphasis on improving the design, and ensuring
product operation is safe and reliable during the useful life of the equipment
What is the RPN score formula? what if it’s above 100?
RPN = O x S x D (Occurence, severity and detectability)
Why are the RPN scores useful? (6)
• Highlight the need for design improvement
• Highlight priority areas for focusing limited resources
• Highlight the need for different levels of inspection, e.g. statistical process control
(SPC), 100% inspection, no inspection
• Identify parts which have redundant function
• Prioritise those suppliers to which attention needs to be given
• Provide a basis for measures of performance
