Equipment Variation 2. Definitions: • Resolution/Discrimination • Capability to detect the smallest tolerable changes • Inadequate Measurement Units • Measurement units too large to detect variation present • Guideline: “10 Bucket Rule” • Increments Measurement Systems • Examples • Precision gage • Data collection form • Survey • School entrance exam • Customer satisfaction • On-time delivery report What is your system ? © 2001 No exceptions.

It will show up especially in the attempt to determine reproducibility, where it is generally quite significant. See our User Agreement and Privacy Policy. Mr. Choose Method Of Analysis Enter Gage Info and Options ANOVA method is preferred • Gives more information © 2001 Six Sigma Academy 65 66.

Select “Single Column” if data is stacked 1. Select “Multiple Columns” if data is un-stacked 2. This gage is deemed acceptable, no action is required. Six Step Variables MSA 1. 2. 3. 4. 5. 6.

For example, the repeatability contribution to the total variation could be estimated by: Honest ratio 6: which is 2.45 percent rather than the 15.65 percent erroneously found earlier. The product variation is estimated to be: Formula 4: Finally, the total variation for the set of product measurements is estimated by combining the repeatability, the reproducibility, and the product variation Find out more about Dr. If the gage capability is marginal (as high as 30% of study variation) and the process is operating at a high capability (Ppk greater than 2), then the gage is probably

Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. In my book I also discuss how to solve the problem of a lack of degrees of freedom for the product variation estimate. Create a clipboard You just clipped your first slide! Figure 3: Interpreting the results for the gauge R&R study for gasket thickness Here we find that the measurement system used to measure the gaskets in figure 1 is simultaneously marginal,

Since that is unlikely to happen anytime soon, you need to stop using the erroneous ratios of the AIAG gauge R&R study. Using the combined R&R, the 99 percent manufacturing specifications become 156 mils to 214 mils, which represents a loss of 27 percent rather than the 43 percent erroneously computed above. Durch die Nutzung unserer Dienste erklären Sie sich damit einverstanden, dass wir Cookies setzen.Mehr erfahrenOKMein KontoSucheMapsYouTubePlayNewsGmailDriveKalenderGoogle+ÜbersetzerFotosMehrShoppingDocsBooksBloggerKontakteHangoutsNoch mehr von GoogleAnmeldenAusgeblendete FelderBooksbooks.google.dehttps://books.google.de/books/about/Heat_Treating.html?hl=de&id=m-SSXC_FZe4C&utm_source=gb-gplus-shareHeat TreatingMeine BücherHilfeErweiterte BuchsucheE-Book kaufen - 15,21 €Nach Druckexemplar suchenASM InternationalAmazon.deBuch.deBuchkatalog.deLibri.deWeltbild.deIn Bücherei suchenAlle We ask them to repeat the measurement two times to determine the repeatability component.

I personally quit using it back in the 1980s. Dossett, Robert E. The results of the measurements are shown in the table below: From this table, we can see that measuring instrument A is precise (since it has less variation) but it is As the author of 25 books and hundreds of articles, he is one of the leading authorities on statistical process control and applied data analysis.

Using these guidelines we would interpret the ratios computed earlier,as shown in figure 3. Attribute MSA - MINITAB Graphical Output Date of study: 1/03/2001 Reported by: Jose Name of product: XYZ Report Misc: Assessment Agreement Lower variation within appraiser Within Appraiser Appraiser vs Standard Lower Capability Which Might Need The Most Attention? We use them to measure a continuous primary metric such as length whose true length is 100.

Facebook Twitter LinkedIn Google+ Link Public clipboards featuring this slide × No public clipboards found for this slide × Save the most important slides with Clipping Clipping is a handy Unfortunately, the original procedure contained some fundamental problems that have not been corrected over the years. Therefore, when we take the P/TV or P/T ratio, where P is the Precision of the Gage (5.15* sms) it is well below 30%. Components Of Measurement Error • • • • • • Resolution/Discrimination Accuracy (bias effects) Linearity Stability (consistency) Repeatability-test-retest (Precision) Reproducibility (Precision) Each component of measurement error can contribute to variation, causing

Resolution/Discrimination Resolution? OK Accuracy/Bias? A could be a laser measuring device and B could be the measuring tape. Scenario #1 15% - % Study 15% - % Tolerance LSL USL Tolerance Observed (Total Variation) Part Contribution (Part Variation) 5 0 6 0 7 0 8 0 9 0 Gage

Wheeler welcomes your questions. I'm personally not in favor of R&R studies to test the reliability of a measuring system, I would rather break it down to its components, that is devices, people, methods and Accuracy/Bias Difference between the observed average value of measurements and the master value Master Value (Reference Standard) Master value is an accepted, traceable reference standard © 2001 Six Sigma Academy Average OK Linearity?

They allow you to learn and use the correct formulas for evaluating the measurement process. They gave me a award and changed very little in the procedure. Types of Measurement System Analysis • Operational Definitions • Walking the Process • Gage R&R • Variable Data • Attribute Data © 2001 Six Sigma Academy 8 9. Therefore improvement of the measurement system is required. 98 Recommended Flipping the Classroom Strategic Planning Fundamentals Gamification of Learning 10.

Figure 1: The gasket thickness data The average and range are shown for each of the 15 pairs of measurements in figure 1. Login or register to post comments Six Sigma Columns Davis Balestracci October 17, 2016 Some Final Thoughts on DOE—for Everyone Harish Jose September 28, 2016 Kaizen—Can It Go Wrong? I suggest that you do the same, starting immediately. You might start by showing them a copy of this paper.

Reproducibility error refers to difference in readings obtained when different people are measuring the part using the same instrument. We could also take exception with the way the AIAG study uses adjustment terms for Repeatability and yet fails to use adjustment terms for the product variation (where it inappropriately uses MeadowsCRC Press, 28.05.1998 - 455 Seiten 0 Rezensionenhttps://books.google.de/books/about/Measurement_of_Geometric_Tolerances_in_M.html?hl=de&id=Ms7lVOepeNsCThis insightful reference demonstrates a system of measurement, inspection, gaging, geometric tolerancing, and fixturing of products in full compliance with the American National Standards In this example the Gage Precision - P (5.15* sms) compared to the Total Variation - PV (5.15*sTotal) P/TV is very small - 5%.

Continue to download. Accuracy/Bias Resolution? The second problem is the sample size used. As a result, over the past 250 years, different areas of science and engineering have come up with many different ways to deal with the problem.

You should look for differences between operators to give you some indication as to whether it is a training, skill, and/or procedure problem. Enter the data as requested in this analysis and then click on Compute Outputs. Attribute MSA Example 5 Attribute Legend (used in computations) 1 Pass 2 Fail Open file MSA-Attribute.xlsOperator #1 Known Population Sample # 1 2 3 4 5 6 7 8 9 10 So what should you do?

Typically, measurement error occurs during correctly interpreting the measuring instrument, data entry, manipulation of numbers, or reporting. Embed Size (px) Start on Show related SlideShares at end WordPress Shortcode Link Measurement systems analysis v1.1 3,551 views Share Like Download Alexander Polyakov, Industrial Engineer Follow 0 0 0