Tag: OEE Problem Solving

Using TRIZ for Problem Solving – Resources

In our first post on this topic, “Using Triz for Problem Solving – Introduction“, we provided a very basic introduction to TRIZ.  In the spirit of TRIZ, it is not our intent to rewrite or redefine the TRIZ process when excellent information is already available.  Our intent is to identify the few of the many excellent and exceptional resources that we have found.

What is TRIZ?

To learn more about TRIZ and it’s applications we suggest visiting the following web sites that present a tremendous amount of information on the development and application of TRIZ.

TRIZ Principles

40 Inventive Principles with Examples:

Examples for each of the 40 Inventive Principles can be found at the following link:  http://www.triz-journal.com/archives/1997/07/b/index.html

TRIZ Resources

The Contradiction matrix:

As you will have learned from reading the “What is TRIZ?” page from the link above, one of the tools of TRIZ is the Contradiction Matrix that consists of 40 elements.  The TRIZ Contradiction Matrix is available as an Excel Spreadsheet through the following link:

http://www.triz-journal.com/archives/1997/07/matrix.xls

The TRIZ Journal ARTICLES:

The Triz Journal presents many informative articles.  One very intriguing article, “TRIZ / Systematic Innovation Enhances Hoshin Kanri“, by Darrell Mann and Ellen Domb, demonstrates the principles of TRIZ in a unique application.

An excellent article, “Create a High Performance Culture with Hoshin Kanri”, by Frank Deno can be found at the following link http://www.realinnovation.com/content/c080623a.asp

WEB Sites:

TRIZ Books:

A number of books are available on the topic of TRIZ.  Click here to preview the selections currently available.

TRIZ Challenges:

TRIZ is not without its challenges.  Although TRIZ has evolved over many years, it still remains relatively unknown and few companies seem to be ready to adopt this problem solving method.

An excellent article, “Enhancing TRIZ with Dr. Deming’s Philosophy“, by Ellen Domb and Bill Bellows, presents some interesting insights to this challenge.

We typically tend to avoid “labels” for the method we are using to solve a specific problem.  Unlike a surgeon “requesting specific tools (scalpel)” while performing an operation, our strategy tends to be a blended “hybrid” approach to problem solving; TRIZ happens to be one of the more effective methods that we have learned to use over the past few years.

The acceptance of TRIZ may be attributed to the current struggles many companies experience simply attempting to complete an 8D or 5-Why.  Of course, that would only be true of companies who are void of the Lean principles and methods – right?  TRIZ also has a perceived complexity that does not lend itself to ready adaptation as a company-wide problem solving tool.

We would recommend reviewing the many available books on the topic of TRIZ.  Integrating a tool such as TRIZ will require someone to become the leading expert.  Click here to see the various book selections that are available.

Unfortunately, for many companies, the discipline or the structure is simply not there to support effective problem solving efforts.  Perhaps if more time was spent solving the real problems, they would have more time to solve problems not yet realized.

Remember to get your TRIZ – Click Here!

Until Next Time – STAY Lean!

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How to Improve OEE – Any Questions?

Ask any Quality or Engineering manager and they will tell you that measurement systems are valuable tools to identify problems and opportunities.  The measurement system itself is not the answer – it is the data source, the EVIDENCE that drives the questions.  It is a part of the discovery and validation process to confirm the opportunity or problem and the effectiveness of the solutions to resolve it.

A well integrated OEE system should provide the data to answer the questions on everyone’s mind, “What do we need to do to improve?” or “Why aren’t we improving?”  The simple answer is, “We need to fix it.”  Of course the real question may not be, “What do we need to fix?” but, “Why did it break?”

Yes, we will likely have to replace the part(s) that failed to get the line back up and running, but what really caused the failure to occur?  What was the real root cause?  This introductory post to problem solving and root cause analysis will kick start some of the techniques used to solve problems effectively.

The Problem Statement:

The key to effective problem solving starts with identifying the problem to be solved.  This is typically a brief statement describing the problem.  For external concerns, the problem is usually stated in customer terms.

This post presents some simple examples of problems to be solved.  You will quickly discover that defining the problem may not be as simple as it looks.  We will discuss this in more depth in our future posts.

Root Cause Analysis

Identifying the real root cause(s) for the failure is the secret to successful problem solving.  The method you use to arrive at the root cause should allow you to confirm and validate your solution before taking action.  Here is an important point to remember:

Do not confuse symptoms with root causes.  

For example, you are driving down the road and suddenly find yourself struggling to maintain control of your vehicle.  Your expert driving skills allow you to pull over and stop on the side of the road.  You get out of the car and walk around to discover that you have a flat tire.  The flat tire is a symptom – not the root cause.

As luck would have it, a police officer who just happened to be following you in an unmarked car, notices your sudden erratic driving behavior and charges you with recklessness and careless driving.  Since none of the tires on the police car are flat, the officer presumes the condition of your vehicle is the direct result of your poor driving skills and bad habits after many years on the road.  Another point to remember:

Do not jump to conclusions

You, like many people, would argue that your many years of driving provided you with the experience necessary to avert danger.  The officer quickly recognizes that your many years of experience have caused you to lose perspective of the potential hazards of driving.  The officer advises that your driving record shows no record of any tickets or accidents and clearly suggests that you have had very few “experiences” with the law and minimal exposure to poor road conditions.

The officer proceeds to charge you, the operator, because you simply weren’t paying attention to the conditions and potential hazards of the road.  You are given a ticket to serve as a reminder to pay more attention to the road and to be mindful of your driving habits in the future.  Then to add insult to injury, the officer advises you to fix your tire and drive carefully. 

Unforgiving of the circumstances and since quota’s have to be met, the charges stand and you find yourself on your way to court.  As you sit in your vehicle, stunned that you just got a ticket for getting a flat tire, you are conflicted and fuming because the officer blamed you, your poor driving skills, and your bad habits for driving recklessly down the road!  The following tip will help you remember:

Operator Error is not a Root Cause

Many times, management is too quick to attribute the root cause to operator error.

5 WHY Analysis

One of the best methods for identifying the real root cause is the 5-Why approach.  The concept of asking the question “WHY?” five times is quite simple.  In practice though, you will find it may not be that easy.  Why?  Because the wrong answer will lead you through a continuing series of wrong answers that ultimately lead to the wrong conclusion.

There is always more than one answer – Which one is correct?

Referring back to our example of the flat tire, you now need an argument to absolve yourself of any blame for the incident on the highway.  In court, the judge asks, “How you plead to the charges before you?”  You answer, “Not Guilty your honor.”

  1. Why?  While I was driving down the road, I got a flat tire.
  2. Why?  Because all the air ran out of my tire.
  3. Why?  Because there was a hole in it.
  4. Why?  Because the tire didn’t have anti-puncture technology.
  5. Why?  Because the manufacturer didn’t design it properly.

Were it not for my expert driving skills, this situation could have been much worse.  As it was, using my superior driving skills, I successfully managed to maneuver my vehicle, without incident, to the side of the road, averting what could have been a disastrous crash.  Therefore, I request to be completely absolved of any and all wrongful doing and I am filing a class action suit against the tire manufacturer to cover court costs, lost wages, and damages as well as my emotional stress.

Clearly not satisfied, the judge requests you to take a 10 minute break to rethink your case.  On your return to the courtroom, you are prepared to present the following argument:

  1. Why?  While I was driving down the road, I got a flat tire.
  2. Why?  Because all the air ran out of my tire.
  3. Why?  Because there was a hole in it.
  4. Why?  Because there was a nail on the road.
  5. Why?  Because the government refuses to keep the highways clean.

Were it not for my expert driving skills, this situation could have been much worse.  As it was, using my superior driving skills, I successfully managed to maneuver my vehicle, without incident, to the side of the road, averting what could have been a disastrous crash.  Therefore, I am filing a class action suit against the government to cover for court costs, lost wages, and damages as well as my emotional stress.  To resolve this matter quickly, I request that all charges be dropped and I in turn will drop my counter-claim.

The purpose of the above example was to demonstrate how the answer to the question – WHY? – can lead to completely different conclusions.  On one hand we’re ready to sue the tire manufacturer and on the other, we’re ready to take on the government.  If there was indeed a nail on the road, how did it get there?

Don’t Assign Blame

Solving problems and getting to the root cause is not about assigning blame to someone or something.  You can’t blame the government or the tire company for the fact that there was a nail on the road.  It is to easy to assign blame and it happens everywhere, everyday.  Perhaps the nail manufacturer should be sued as well for failing to provide adequate protections should the nail become lost or misplaced.

The question that wasn’t asked is, “Why was the nail on the road?”  The answer may be that it likely fell out of a board or from a truck or trailer that may have been carrying construction materials.  Again, being careful with the answer, we don’t want to come to the conclusion that nails should be banned completely.

On the other hand, it may be worthwhile to advise that all companies and contractors must make a reasonable effort and take appropriate precautions and measures to ensure that all loads are secure and free from loose raw materials.  Any nails must be placed in a sealed container and secured to the vehicle for the purpose of transport.  A maximum fine of $2,000.00 may be imposed and made payable to the “Operator Error Trust Fund.”

Leading the Witness:  The solution BIAS

STOP! – if you think you already know the answer – Stop!  We know that the right question doesn’t always lead to the right answer as we attempted to show in our example.  Another major pitfall is thinking we already have the answer and we just need to frame the questions and answers to support that conclusion.  This isn’t problem solving, this is creative story telling.  Don’t lead your team into following what “appears” to be a logical conclusion – be prepared to prove it.

Don’t Assume Anything – Follow the EVIDENCE

At a minimum, follow the evidence.  What is the data telling you?  It’s time to start thinking like a crime scene investigator (CSI) or good lawyer.  Asking questions and continuing to probe for answers is the secret to uncovering the less obvious and, more than likely, real solution.

Many OEE equipment / software integrators provide the ability to record and track downtime events in real time.  This data is extremely valuable for trouble shooting and problem solving; however, they are not necessarily root causes.  The integrators provide the capability to readily identify what part of the process failed or what is broken.  While this may be the cause of the line down condition, it is not the root cause of the problem.

Do not confuse the Point of Failure (Source) with the Root Cause

Don’t fall into this trap:

  • Supervisor:  “The OEE system report showed that we lost two hours on the paint line last night.”
  • Maintenance:  “Yeah, I saw the report too.  This OEE system tracks everything!”
  • Supervisor:  “Why did the line go down?”
  • Maintenance:  “The A-Tank feed pump overheated.  The OEE system told us exactly which pump failed.  It saved us a ton of time.”
  • Supervisor:  “What did you do?”
  • Maintenance:  “Oh, we replaced it.  The line is running fine now.”
  • Supervisor:  “OK, that’s good.  Thanks.”

End of conversation.

So, WHY did the pump overheat?  Some questions just never get asked, but I’m sure the OEE will be just fine on the next shift.  We recognize that most effective TPM managers are sharper than this.  Our point is that not everyone is looking at the data from the same perspective.

We’ll discuss “How to Improve OEE” in more detail in our next post:  “How to use the 5 Why Approach.”

Until Next Time – STAY lean!

Problem Solving with OEE – Measuring Success

OEE in Perspective

As mentioned in our previous posts, OEE is a terrific metric for measuring and monitoring ongoing performance in your operation.  However, like many metrics, it can become the focus rather than the gage of performance it is intended to be.

The objective of measuring OEE is to identify opportunities where improvements can be made or to determine whether the changes to your process provided the results you were seeking to achieve.  Lean organizations predict performance expectations and document the reasons to support the anticipated results .  The measurement system used to monitor performance serves as a gauge to determine whether the reasons for the actual outcomes were valid.  A “miss” to target indicates that something is wrong with the reasoning – whether the result is positive or negative.

Lean organizations are learning continually and recognize the need to understand why and how processes work.  Predicting results with supported documentation verifies the level of understanding of the process itself.  Failing to predict the result is an indicator that the process is not yet fully understood.

Problem Solving with OEE

Improvement strategies that are driven by OEE should cause the focus to shift to specific elements or areas in your operation such as reduction in tool change-over or setup time, improved material handling strategies, or quality improvement initiatives.  Focusing on the basic tenets of Lean will ultimately lead to improvements in OEE.  See the process in operation (first-hand), identify opportunities for improvement, immediately resolve,  implement and document corrective actions, then share the knowledge with the team and the company.

Understanding and Managing Variance:

OEE data is subject to variation like any other process in your operation.  What are the sources of variation?  If there is a constant effort to improve performance, then you would expect to see positive performance trends.  However, monitoring OEE and attempting to maintain positive performance trends can be a real challenge if the variances are left unchecked.

Availability

What if change-over times or setup times have been dramatically reduced?  Rather than setting a job to run once a week, it has now been decided to run it daily (five times per week).  What if the total downtime was the same to make the same number of parts over the same period of time?  Did we make an improvement?

The availability factor may very well be the same.  We would suggest that, yes, a signficant improvement was made.  While the OEE may remain the same, the inventory turns may increase substantially and certainly the inventory on hand could be converted into sales much more readily.  So, the improvement will ultimately be measured by a different metric.

Performance

Cycle time reductions are typically used to demonstrate improvements in the reported OEE.  In some cases, methods have been changed to improve the throughput of the process, in other cases the process was never optimized from the start.  In other instances, parts are run on a different and faster machine resulting in higher rates of production.  The latter case does not necessarily mean the OEE has improved since the base line used to measure it has changed.

Quality

Another example pertains to manual operations ultimately controlled through human effort.  The standard cycle time for calculating OEE is based on one operator running the machine.  In an effort to improve productivity, a second operator is added.  The performance factor of the operation may improve, however, the conditions have changed.  The perceived OEE improvement may not be an improvement at all.  Another metric such as Labour Variance or Efficiency may actually show a decline.

Another perceived improvement pertains to Quality.  Hopefully there aren’t to many examples like this one – changing the acceptance criteria to allow more parts to pass as acceptable, fit for function, or saleable product (although it is possible that the original standards were too high).

Standards

Changing standards is not the same as changing the process.  Consider another more obvious example pertaining to availability.  Assume the change over time for a process is 3o minutes and the total planned production time is 1 hour (including change over time).  For simplicity of the calculation no other downtime is assumed.  The availability in this case is 50% ((60 – 30) / 60).

To “improve” the availability we could have run for another hour and the resulting availability would be 75% (120 – 30) / 120.  The availability will show an improvement but the change-over process itself has not changed.  This is clearly an example of time management, perhaps even inventory control, not process change.

This last example also demonstrates why comparing shifts may be compromised when using OEE as a stand-alone metric.  What if one shift completed the setup in 20 minutes and could only run for 30 minutes before the shift was over (Availability = 60%).  The next shift comes in and runs for 8 hours without incident or down time (Availability = 100%).  Which shift really did a better job all other factors being equal?

Caution

When working with OEE, be careful how the results are used and certainly consider how the results could be compromised if the culture has not adopted the real meaning of Lean Thinking.  The metric is there to help you improve your operation – not figure out ways to beat the system!

FREE Downloads

We are currently offering our Excel OEE Spreadsheet Templates and example files at no charge.  You can download our files from the ORANGE BOX on the sidebar titled “FREE DOWNLOADS” or click on the FREE Downloads Page.  These files can be used as is and can be easily modified to suit many different manufacturing processes.  There are no hidden files, formulas, or macros and no obligations for the services provided here.

Please forward your questions, comments, or suggestions to LeanExecution@gmail.com.  To request our services for a specific project, please send your inquiries to Vergence.Consulting@gmail.com.

We welcome your feedback and thank you for visiting.

Until Next Time – STAY Lean!

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