Just a quick note to inform everyone that I am back after 2 surgeries. Still healing but all has come out well. As I begin to ramp up again, I am preparing for a trip to Australia, India, and China to teach Special Characteristics, APQP and FMEA. I just finished a teaching an FMEA course at John Deere for the SQE group. This was a very fun class for me as the group was dynamic and had many questions. I hope to hear more from all of you through email as such in the near future as we continue on our never ending relentless pursuit of quality improvement.
What do I mean by this statement? Using RPN thresholds to take actions is not the intent of the FMEA tool. This is according to AIAG, SAE and other authorities. There are three paths that one takes when developing an FMEA:
- Severity first when 9 or 10
- Take action to error proof to eliminate the Failure Mode
- High Occurrence (4 or higher) when linked to higher severity 5 or more
- Take action to error proof the cause or make it more capable
- Detection number too high greater than 3 when a Cause and Failure Mode combination indicates testing or inspection for a probable cause is not adequate.
- Take action to improve testing (DFMEA) or Inspection methods (PFMEA)
RPN’s are then assigned to the Actions from the three above action drivers. The new RPN calculated after the action is compared to the RPN assigned to the action to see what the delta or difference is. Improvement is expected in the category that the action was developed.
If there are any comments to this strategy please write and comment or give us a call at (248) 280-4800. Read the rest of this entry »
I am in my living room on a Saturday morning and was just thinking about how often things go wrong in our fast paced world. Case in point, I was at my doctor for my full physical and we started discussing Quality Control and Quality Assurance and the topic came up as to medical procedure quality. I have been involed in FMEA developement for hospital process and surgical protocol and have noticed a fairly strong CONTROL emphasis as a result of those activities. Control in the sense of preventing a failure. An example would be the double checking of your bar code on your wrist and the additional questioning by the care giver regarding your name and purpose of your hospital stay. These controls and the FMEA process outputs driving this level scrutiny has made your hospital alittle more safe.
8D or Eight Disciplines for Problem Solving uses many of the most common tools for developing a path to get to the Root Cause. 8D does have one intersting characteristic. The 8D uses the IS/IS NOT exercise to gather facts and do comparative analysis for the purpose of determining where the root cause is not. Let me repaet that. The 8D process attempts to gather facts to prove where the problem is not. After sufficient facts have been gathered the possible causes are eliminated by proving they are not the root cause. This is typically not understood when using 8D as most people are trying to find the root cause directly instead of finding out what it is not.
Can the FMEA process be lean? Based on many experiences with many types of industries, I can say that the vast majority of activity is redundant. Team activity in FMEA should be restricted to only 4 items of discussion only.
- New Content
- Changes to current content
- Past failures
- Increased demand stresses on Carry-over or processes.
The last of these will be my topic of the day. What are increased demand stresses? Demand stresses are based on the noise factors (not audible generally) that are not controlled by the engineer. Noises like Customer usage, Degradation over time, Interfaces with other systems, Environment, and variation sensitivity, are the bases of Robust Engineering. The engineer must attempt to understand these NOISES as they may affect his or her design. The ability of the design (its capacity) to deliver the desired outcomes in the presence of the Demand stress (expected and unexpected) determines how effectively the design satisfies customers. This sounds alittle technical but think of it this way. If an unknown demand on a carryover part is present when the product or process is being used may translate in failure. This means that carryover products and processes which did well in the past may actually fail in the future deployment. Some of my customers indicate that up to 40% of failure comes from what worked in the past but now does not. In order to include these items in future analysis we still need to consider NOISES and their impact on current processes and products.
Currently many companies lean out the FMEA process by creating family FMEA’s. This is not wrong but it can drive the type of behavior that does not consider new or changed NOISES (Increased DEMAND Stress). Currently a cut and paste mentality exists where it does not allow for a efficient review of current designs with respect to new Demands.
In Summary, Lean FMEA is not about cut and paste but instead organization of knowns Causes and Failure Modes, both potential and actual. The additional review of these knowns in relation to new DEMANDS is necessary to assure success.
Just returned to North America from China and India. I was teaching APQP and PPAP to several enthusiastic groups in both China and India. With emerging markets expanding at an exponential rate, the need for supply chain management and development is very strong. Suppliers make up to 70% of the value in most big products produced in these regions. The supply chain is also as diverse as he cultures that I have visited there. Some suppliers are transplants form Europe or North America and are as sophisticated as their inspirations in NA and the EU, while others are just getting started or have been suppliers for a very long time but without the extra expectations of the change management process of APQP. I must say that the groups that I visited were very enthusiastic and quite interested in the possible benefits of Quality Planning. I was very explicit about the danger of the checklist mentality and the temptation to just complete forms and not get the true benefits of FMEA, Special Characteristics and Collaboration. This message is key to ensuring that intelligent supply chain development is the outcome instead of the documentation exercise so often incorrectly depicted as what APQP is.
Just a note to my new friends in China and India, Wow, I had a great time, thanks for the hospitality and the great interchange, questions, and learning experience. I will always remember my trip and your friendliness.
Lee
In Beijing this week teaching 40 or so engineers and suppliers development people in APQP.The tools used in APQP such as FMEA and Design for Assembly were of great interest. I was very pleased at the level of intensity that was demonstrated by the participants. (trying not to fall asleep) But seriously, these tools which have been introduced are not well understood even though many examples exist of their use. I suspect they are filling in the form without getting much value from the tool (FMEA) What is really rewarding to me is when they “get it” and they begin to listen and ask questions and you can see that they will now be using the FMEA as it was intended - to prevent failure and improve controls.
In Canada this week and boy is it cold. I was teaching an 8D class with the Global 8D Ford twist. While teaching we got into a discussion on the FMEA relationship to the 8D. My response was that these two processes are one in the same except FMEA is an 8D that we do before the need for an 8D. The FMEA Failure Mode corresponds to the problem statement and description on the 8D. The effects of failure in the FMEA and customer symptom in 8D are related and the causes in the FMEA are the possible causes and the most likely causes in 8D. The MLC have higher Occurrence ratings. The FMEA is usually related to the D7 (prevention) step but I want you to take a look at the FMEA at the D4 step just to see the legacy of causes already captured from the FMEA. Updating the FMEA is also a way to assure that the 8D talks to the FMEA. If you would like more on this topic please write me or comment or go to www.quality-one.com
I am in Japan this week training and mentoring in APQP and FMEA. Once here and working with my customer teams, I noticed how difficult it might be to understand the FMEA linkage.
Much has been said about the linkage between Design FMEA and Process FMEA. My thoughts on this are to be as prescriptive as possible. I am very much a supporter of the idea that there is an intermediate step between the two documents. That intermediate step is a Characteristic Matrix. The Characteristics Matrix is actually part of the QFD process, where the House of Quality converts Voice of the Customer to requirements definitions. Second phase has the requirements being translated to specifications at the platform, system or component level. This output enters the Design FMEA as the function with measures. Causes of failure once converted to dimension or feature is transferred over to the PFMEA, but confusion exists at this stage. Process people often state that they cannot do a Process FMEA without the Design FMEA. This is principally correct and wrong simultaneously. The outputs of the Design FMEA is what we need, and there are many parts where no outputs will be necessary. More on this point on a further blog entry. The Characteristics Matrix provides a clear way to transfer the Design FMEA outputs to the Process FMEA. The linkage exists in three areas:
- Characteristic
- Effect of Failure (on the customer)
- Severity assigned to the Design Failure Mode and Cause Mechanism.
These three items drive an additional Process FMEA effort for the process steps that affect theses characteristics. The Process FMEA does not have any choice on Severity for the characteristic as it is dictated by the Design FMEA. This assures that the Process is analyzed on its’ impact on that characteristic. For more on this idea stay tuned. Please comment if you want to continue this discussion.
I can think of no better technique than FMEA to get engineers together and “hash out” the possible failures of a design or process. The word HASH is appropriate because of all the ingredients necessary to get it to taste good. Many FMEA’s are not developed with enough ingredients to assure that the true issues come out.
All engineers believe they have done a great job, this is not what the FMEA is about. The FMEA is about where and when unknowns can affect performance. The testing and verification of the design or validation of the process should be a confirmation of the FMEA outputs. When risk is uncovered, the actions that come from the FMEA should affect both the design of the product and/or process but also the testing for verification and validation. Too many times we hear “we will test for that” But what if it fails? Will there be enough time to redesign and reconfirm the design? These issues should be discussed during the FMEA process.