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1. M t 1 A t 3 Instantaneous failure rate vs cumulative time which is Option R Option I superimposed for WinSMITH Visual The line slope is BR 1 This method is often helpful for development activities c t ABET 4 Instantaneous MTBF or MTTF vs cumulative time This is Option T Option I superimposed for WinSMITH Visual The trend line slope is 1 B m t 1 AB t P 5 Cumulative failure rate vs cumulative time which is Option R for WinSMITH Visual The line slope is B 1 C t Atf The most used features are 1 2 and 3 Often you will see the term a 1 8 in European literature Suppose we have the following data set Cumulative time 316 2 752 1 1248 6 1788 9 2364 4 2969 5 3600 6 4254 6 4929 5 5623 4 Cumulative failures 1 2 3 4 5 6 7 8 9 10 What are P A what do the symbols mean and when will failure number 11 12 15 and 20 occur Enter the data click on the C A icon view the plot interpret the data and click the ord tab for failures Page 20 Figure V7 shows the main screen with a Crow AMSAA plot and the results lt WinSMITH TM isual 4 0P 32 gt a NAAA ag Icon Tab For Forecast Beta 0 8 Lambda 0 01 r42 1 0 Point6 Points 3600 6x x1 375 8063x1 14 4254 6x8x1 386 7804x1 1 4929 5x9x1 Figure V7 WinSMITH Visual Crow AMSAA Plot Click on the tab above the graph in Figure V7 to get the statistics and the failure forecast as show2. BF Plot Instantaneous Failure Rate Other options under the C A icon allow you to have the display to fit your needs such as the rate of failure occurrences Option R the survival transform which is 1 Rate Option S which will produce a curved line of both survival and MTBF and other options to be discussed later End of excerpts from the training manual For more details you will need to purchase the WinSMITH Weibull and WinSMITH Visual Instruction Manual and Guide Contact Barringer amp Associates at http www barringerl com Phone 1 281 852 6810 FAX 1 281 852 3749 Email hpaul barringerl com Page 23
3. RAK Te Era CON acta lo ue actin bie ase EE 9 Py EMG Ey EE EE 10 14 Another Quick Analysis Using Optimum Replacement Intervals 11 15 High Resolution Graphical Output es rar skeerne ARENAER 12 l6 Addme Labels T GraphS eases EE 14 PEPENE GaP EE 16 S The E EE 18 19 Demonstrate Sample Data Input 25 20 DIS IBU MOM ANALY SIS ee ee ee 26 21 Prediction Precise Reading From Plot Likelihood Plot 28 22 Failure Forecast For Quantity Expected Abernethy Risk Analysis 28 GE E EE AER 32 SC Ee EE 35 S S VNC IM OC VEO UN 2 crc EE 36 26 Oily Ee E EE 37 27 Taree Parameter Curve EE 37 28 Weibayes MEE NEE EE 39 29 Zoom Hide PBomt Set Ouantntv ccc cece cece eee cece renee ener eee eee eee e es 40 Additonal FFE ATA IV SIS de ses een ensues Giri bese leet TT tae Cis 42 31 Accelerated Test Degradation DEEN 42 32 Mixture t Process e 45 BJ MTOM ET EEN 48 34 Bach Operant EE 48 Appendix A The WinSMITH Weibull Icon Tour 5 INS Wye EE 51 EE EE EE 5I OPETE Od ee 53 LV EE 54 PIOTEREP OF NEE 54 6211 01 ks EE 56 EIER Eeer 56 Dice demonstrate sampl EE 58 IR Si ee ET 59 Optimum Replacement Interval 0c ccc cece cee eee ener eee neeees 60 Predict Precise Plot E EE 61 Quantify Expected Abernethy Risk Analvas ccc cc eee cece cece es 62 Test Regu emei EE 64 EE EE INA E A EE ETA dae urinate hee 65 Conndence nterna Eege Ee 65 Ee 67 Egeter ER 68 Ony EE 70 PAS E E E EE A E E E E ET 70 We
4. See Figure W2 for data appearance before and after entry Data quantity f not otherwise specified the default quantity of 1 is automatically added by the software SMa avast Data in Point2 Data in rank entry sequence i order after the before mouse mouse pointer pointer is moved is moved over over graph the graph Spreadsheet data as entered Data automatically ordered Figure W2 WinSMITH Weibull Spreadsheet During And After Data Entry Page 12 2 Make A Probability Plot Using the spreadsheet data in Figure W2 move the mouse pointer to the small size plot The thumbnail plot appears as shown in Figure W3 Select Set 1 Point 7 ae Jm est KT Em Weibull 2 E JE amp Figure W3 WinSMITH Weibull Thumbnail Plot Enlarge the thumbnail plot by mouse click It will go to full screen as in Figure W4 Click Results Minimize RESULTS W rr Rank regression method Characteristic life n Cumulative distribution function Coefficient of determination Eta Beta r 2 n s YR2002 21 4 2 007 0 981 5 0 MO1D13 wz 10 Line slope P SES Datum Units 5 data 0 suspension Figure W4 WinSMITH Weibull Full Scale Plot Remove the full screen plot by touching the ESCAPE key or left click with the mouse Page 13 3 How To Interpret The Weibull Probability Plot In Figure W4 notice The probability plot is a Weibull plot and it uses ran
5. WinSMITH Weibull and WinSMITH Visual Instruction Manual and Guide Paul Barringer P E Barringer amp Associates Inc P O Box 3985 Humble TX 77347 3985 Phone 1 281 852 6810 FAX 1 281 852 3749 Email hpaul barringer1l com Web http www barringer1 com Simple Tools Strong Results WinSMITH Weibull and WinSMITH Visual Software Instruction Manual and Guide First Edition All rights reserved Reproduction or translation of any part of this work beyond that permitted by Section 107 or 108 of the 1976 United States Copyright Act without permission of the copyright author is unlawful Requests for permission should be addressed to the author s Weibull Methodology by Robert B Abernethy 536 Oyster Road North Palm Beach Florida 33408 4328 Phone 561 842 4082 FAX 561 842 4082 E mail weibull worldnet att net Software by Wes Fulton Presentation by Paul Barringer Fulton Findings TM Barringer amp Associates Inc 1251 W Sepulveda Blvd PMB 800 P O Box 3985 Torrance CA 90502 Humble TX 77347 3985 Phone 310 548 6358 Phone 281 852 6810 FAX 310 548 6358 FAX 281 852 3749 E mail wes weibullnews com E mail hpaul barringer com Website http www weibullnews com Website http www barringerl com Distributed by Dr Abernethy Wes Fulton and Paul Barringer Printing History Every printing includes updated material First Edition First Printing February 2002 Second Printing April 2002 Trademar
6. e process is called non homogenous The following explains how to interpret the Crow AMSAA plots under the C A icon with options C A data can only have suspensions at the end of the dataset where the data is entered with suspended time and the same number of failures as last reported eg 1000 4 105054 The Crow AMSAA technique has three widely used methods and two less widely used rates each with cumulative time on the X axis and most produce straight lines for stable processes on log log plots 1 Cumulative failure events vs cumulative time this is the default method which produces a line slope of B if B lt 1 failures are occurring more slowly if B 1 no change in the failure rate and if B gt 1 then failures are occurring more quickly and A which is the Y axis intercept identifying MTBF or MTTF 1 A This is the WinSMITH Visual default method involving a nose count of events and time It is useful for predicting future failures and identifying cusps where significant events have occurred N t A 2 Cumulative MTBF or MTTF vs cumulative time which requires a transform of the Y axis and thus the actual line slope of the trend line is 1 8 This is Option T for WinSMITH Visual This method requires a transform of the Y axis cumulative time cumulative failures The direction of the curve is a pointer for audiences with attention deficiencies up for improvements down for deterioration and sideways for no change in reliability
7. he icons for WinSMITH Visual Data Form Y Scale Figure 4 WinSMITH Visual Icon Definitions xi Notice each software has a spreadsheet for data entry a thumb size graph and special icons for peforming the calculation or routine chores If you prefer you can use the pull down menus to perform the operations Su WinSMITH Weibull Software An Excerpt From The Manual 1 Manual Data Input The spreadsheet becomes active when you click in the sheet just like occurs with Excel and it changes appearance to give you clues the sheet is active see Figure W1 Delete cell s Click this icon for 1 Click in spreadsheet Cut data cell s expanding the full 2 Enter data here in the Copy cell s screen spreadsheet active data entry box Paste data Press the Enter key S a Data O Newsa E Accept data entry or press the enter key Spreadsheet before click in a cell Spreadsheet after click Figure W1 WinSMITH Weibull Spreadsheet Use the active data entry box to enter data 8 14 17 21 33 you do not need to order the data by use of the edit box such as 8 Enter 14 Enter 33 Enter Check for data input errors by viewing the data BEFORE you move the mouse over the thumbnail graph or return to the main screen When the mouse is moved over the graph the data are automatically ordered and you loose the input arrangement If the data entry is a suspension enter a minus sign before the number
8. he probability plotting software the data does not change after entry If data is input in the wrong format e g Y scale X scale a data transform icon is discussed below to unscramble the error without data re entry Use the active box on the spreadsheet to enter data 2x1 4x2 6x3 8x4 10x5 the data must be in the sequence your want it to appear on the plot following the format X data Y data Quantity Z data For data entry you can use the asterisk or the x or key to separate the data for use by the software Input the data as 2 4 Enter 472 X data Y data Quantity Z data Enter 10 5 Enter The data will appear as if not otherwise specified the shown in Figure V2 default Quantity is 1 2 How to make a plot When you have finished data entry move the mouse over the thumbnail blank screen and the plot will appear in Figure V3 as data points and without trend lines You can connect the dots by use of the Plot Type icon bottom row left icon and choose curve type as point line line only or point only If you prefer you can fit the data to a variety of different math models found under the Curve Fit icon on the bottom row third from the left Interpretation of the plot requires no comment Data Entry Format Page 17 lt WinSMITH TM Visual 4 0N 32 gt Come JE Dopor bebes Tools Help Visual Z Data Figure V3 WinSMITH Visual Spreadsheet Thumbnail Plot En
9. ilBayos lParamcter serene serne DERNE EEA EN 71 ZOOM AGC EET TE T E E EAE EET T2 Additional Fulton Findings Programs cece cece cece cece eeeeeaennees 73 Accelerated Test D SHA da HOR dee 73 Ka 74 EE 75 vi WinSMITH Visual Software Tes leed Eer ee EE EE 76 Do HON POsMaKe APO EE 76 3 How Lo Tmport A Y Data From ExCe EE 78 A EENEG EE E A A EE ASEN 78 5 gt Make A CroW EE 79 Os ODS EE 79 den INAO E E A E E E AEA e 83 Se DOUP GE 83 D IPE Ge e EE 84 UAW D EE 84 PRC VOLUN EE 85 EU EE 86 VS Pel OUPO NCO EE 86 14 Dice Icon Demonstrate Sample eege ee Ehe 88 15 Add A Function Without Use Of A Dataser 0c ccc ccc cece eee e eee e eee e eee eees 88 16 Crow AMSAA Duane Reliability Growth Plot 89 Dis Precise PIOL RCAC EE 92 IS EK Pe CULV E 92 FO AG WS ey EE 92 ZO AC UEV ET EE 92 2 ranstorm Change TO Data EE 93 22 7 00m de Ploy Sey QUANULY cece be Ee 93 E NOCIUONAL FF ANAIS S overser tenors case tained ager R EE EEE ENE 94 2A DOr NaO EE 94 Vil Appendix B The WinSMITH Visual Icon Tour 95 NN 0 GE 95 e a cle eee eee en ime ren en Or Mena ai ae oe ne eer E ee ee 95 Je W Pile ele EE 97 or EE 98 enee EE E NA 98 Eege 99 PGMA EE 102 Dice Icon Demonstrate Sample eieiei Seege eege 102 Wrath Lea EE 102 Crow AMSAAMA DUAN DEE 103 S KEE EE 104 i FE 1 GE 105 Plot EE n 105 EIDE ee 105 CUNE T EEN 106 Transform Make Changes ToDarat 0 0 cece cece cen eee eeeeeees 107 Z
10. k and Copyright Notice Laserjet HPGL and Deskjet are trademarks belonging to Hewlitt Packard Inc PC XT AT PS2 are trademarks belonging to IBM Inc Windows MS DOS Excel Powerpoint and Word are trademarks belonging to Microsoft Corporation Lotus is a trademark belonging to Lotus Development Corporation The New Weibull Handbook is copyrighted by Robert Abernethy PlayTIME Fulton Findings Weibull NEWS WinSMITH and SuperSMITH are trademarks belonging to Wes Fulton All other trademarks and copyrights mentioned herein belong to their respective business units Barringer amp Associates Inc 2002 Preface This manual is intended as a home study guide or a 1 day training class in how to use WinSMITH Weibull and WinSMITH Visual software for those who want more details about the common features of the software This manual does not include the more elaborated subjects and details offered in PlayTIME for SuperSMITH WinSMITH Weibull is a stand alone menu driven probability plotting analysis software program The program provides for best practice Weibull analysis including many techniques not available elsewhere WinSMITH Weibull software is the defacto standard for life data analysis prediction and for evaluating variability and uncertainty in practically all industries Capabilities of WinSMITH Weibull include Weibull normal lognormal and Gumbel lower and upper distributions and variations of these as well as likelihood plotting co
11. k regression calculations methods Shape factor B line slope B is 2 007 it is literally the rise over run calculation for 1 1 graph paper and this is not 1 1 paper suggests a component wear out failure mode The shape factor B is dimensionless Location factor n characteristic life n is 21 4 using raw data units hours years months cycles etc occurs where the trend line crosses the 63 2 double line for the cumulative distribution function CDF The plot contains 5 pieces of data n and 0 suspensions s The coefficient of determination r 2 0 981 is a measure of goodness of fit It says the straight line explains 98 1 of scatter in the data The graph was made on the date of January 13 2002 gt MO1D13YR2002 The small 1 in the upper right hand corner by the triangle symbol is the legend for the graph WSW graphs can contain up to 10 trend line data sets Ten percent Bun or Lio of the population is expected to fail in 7 units of time or less this means 90 of the population will exceed 7 units of time Ninety percent of the population will fail in 32 4 units of time or less Thus 90 10 80 of the population is expected to fail in the range of 7 units of time to 32 4 units of time 4 How To Import One Column Of Data From Excel To WSW A single column of Excel data can be imported into WinSMITH Weibull in two steps as shown in Figure WS Step 1 Step 2 Highlight single Paste data into the spreadsheet by col
12. large the thumbnail plot in Figure V3 by mouse click and it will go full screen as shown in Figure V4 RESULTS PA Scale x Figure V4 WinSMITH Visual Spreadsheet Full Scale Plot Page 18 3 How to Import X Y data from Excel Make sure the data columns in Excel are X data in the left column and Y Data in the right column the highlight the cells and copy To paste the two data columns into WinSMITH Visual click on the paste pot icon DO NOT do a typical Windows paste into WSV because it won t work and select option B from the paste into the spreadsheet dialog box which tells the software how to handle the data The four steps are shown in Figure 5 Copy lt WinSMITH TM Visual 4 0N 32 gt From Excel Visual Lio x 7 Paste ro ahs OE ela e eE e V Select ars E Use Option B For 2 column Source vga Data A Nee Column New Set Value Paste Icon Pom 1 1 i YR2002 Point13 meta Pom 13 Pom 18 0 2 a 5 8 10 1 All 2 v gt a X Sceale x fj Figure V5 WinSMITH Visual Copy Paste From Spreadsheet You can also use the Excel concatenate function to take multiple columns of data and prepare a single column import using option A in Figure 5 during import the concatenate function is explained in the WinSMITH Weibull section of this manual 4 Data Entry Reminder eegal be Res Sege File Ea D Optons A Anelysis B Tools Hee 7 Visual When the mouse pointer is o
13. n in Figure V8 lt ESC gt Exit Set 1 1 of 2 Label 1 ees Point Quantity 10 X Minimum d Y Minimum Maximum z Maximum Total 27847 7 Total 55 Mu 2784 77 Mu 5 5 Sig 1803 453 Sig 3 02765 Forecast m Crow AMSAA Duane Results Data Lambda 0 01 Beta 0 8 rgr r 2 99999761581563 ccc 2 9726 r 2 ccec 2 0274 kay Last Occurrence Quantity 10 At Time al Cumulative Occurrence Expected Next 1 At Time Total Cumulative 711 5 6335 Next 2 At Time Total Cumulative 1439 7063 Next 5 At Time Total Cumulative 3712 9335 Next 10 At Time Total Cumulative 7752 13375 Figure V8 WinSMITH Visual Crow AMSAA Failure Forecast The beta value of 0 8 is less than one This indicates failures are coming more slowly and reliability is improving Future failures are predicted in Figure V8 along with their timing The lambda value of 0 01 is related to the system failure rate at time 1 Of course with beta lt 1 the failure rate will be decreasing with time as the reliability improves and in turn the system mean time LA is growing from 100 at time 1 to 562 3 by the 10 failure If beta were 1 then the system would keep it s failure rate and display a constant mean time 100 Likewise if the system is deteriorating then P gt 1 and expect increasing failure rates and declining mean times to failure Page 21 Crow AMSAA Plot 38833 Crow rgr Failure F
14. n the l WinSMITH Visual spreadsheet a DEDE Wite J MA ies dialog box appears as a reminder S elel el iz concerning data format The dialog tells you the data should be in the format of X Data x Y Data x Pem y Mouse pointer and Quantity The reminder box is fe EE SE about data format shown in Figure V6 with memory jog that wie a minus sign signifies In case your software does not have fPeimm suspended data a tooltip dialog box it may have been turned off To restore the tooltip go to the bottom row of ai icons and select the nght hand icon Under the icon choose option I to restore the tooltip box Figure V6 WinSMITH Visual Tooltip Reminder Box Page 19 5 Make A Crow AMSAA Plot The Crow AMSAA plot in log log format produces a straight line for stable processes as a naturally occurring series of events the trend line models the process and just not the system The task of reliability engineering improvements is to put cusps on the trend lines by make improvements so as to reduce safety problems and reduce costs Thus some judgment is required in selected the trend lines and where line segments start stop Also note that MTBF and cumulative failure rate go with repairable systems and MTTF and instantaneous failure rate go with non repairable systems When the line slope on the Crow AMSAA plot of cumulative failures vs cumulative time is B 1 the process is called a homogenous Poisson process and if B41 th
15. ndows screen by first selecting START Then select and run the appropriate SuperSMITH software program as listed either above the PROGRAMS selection or by first selecting PROGRAMS You should initially see the opening screen with one button displaying lt Y gt Yes I Agree To The Above and another button displaying lt X gt Exit Choose lt Y gt Yes I Agree To The Above to accept the usage disclaimers shown and continue to the main screen The main screen displays all of the options available in the software with icons and menu items for each choice plus a data spreadsheet and a results window Usage Instructions On line User Manual The use of the software is described in detail in the on line HELP file user manual that comes with the software To access the electronic user manual choose the HELP option from the main screen The New Weibull Handbook ISBN 0 9653062 1 6 by Dr Robert B Abernethy is the reference manual for the methodology in our Weibull related software This handbook is the standard reference used to describe Weibull technology and is available separately Server LAN Operation Server LAN use is completely acceptable given that the purchaser s network administration must limit access to one simultaneous user per purchased copy The software reads information from the command line can be different for each user to assist LAN operation Add cXXX to the comand line to store user specific configu
16. nfidence plotting design comparison probabilistic analysis outlier detection optimum replacement failure forecasting test substantiation planning accelerated testing and mixture analysis WinSMITH Visual is a general plotting analysis program with complimentary capability to WinSMITH Weibull Capabilities of WinSMITH Visual include general function plotting transforms curve fitting aggregate cumulative hazard ACH plotting and Crow AMSAA Duane reliability growth plotting The primary functions of the older for MS DOS WeibullSMITH BiWeibullISMITH and MonteCarloSMITH programs are included in WinSMITH Weibull WinSMITH Weibull also includes new mixture analysis capability and process reliability analysis calculations WinSMITH Weibull and WinSMITH Visual software offer more useful options and capabilities than any other current life data analysis program although it is extremely compact in size This wide ranging usefulness is due to the many applications in industries including automotive components aerospace medical electronic electric power petrochemical nuclear rail transport dental materials analysis and others The compact program size allows easy transfer use over networks This training manual is intended to illustrate most of the frequently used capability and many of the applications Hopefully it is helpful for both novice and expert The reference book for all the material herein is The New Weibull Handbo
17. ok authored and published by Dr Robert B Abernethy WinSMITH Weibull and WinSMITH Visual software are written by Wes Fulton You can obtain the latest version of DEMO software for no charge downloads from Wes Fulton s website http www weibullnews com or from Paul Barringer s website http www barringerl com You can also download an electronic copy of the latest WeibulINEWS newsletter published by Wes Fulton and Dr Abernethy See the Barringer website for general introduction to reliability in practice the latest Problem of the Month and details from Dr Abernethy s library posted as no charge downloadable files concerning Weibull Analysis 111 Table of Contents General Information SOM W ALC OC ERR Masaenaanadseravaneeeareaeieee Page 1x Getting Started After Software Is Loaded 0 0 ccc cee e eee e eee e eee se Page x WinSMITH Weibull Probability Plotting Software Icons cece eens Page x WinSMITH Visual General Plotting Software Icons eee ee es Page xi WinSMITH Weibull Software le Manual RE Ch EE 3 2 Make A Propability DEE 2 3 How To Interpret The Weibull Probability Piot 3 4 How To Import One Column Of Data From Excel TowWawW 3 5 How To Import Two Column Data From Excel With Suspensions 4 6 Data EE acter arnt Ee 5 e IG EE 5 8 Quick Plot Using Data From Random Draw Monte Carlo Simulation 6 GR eege Rn al ICOM EEN 7 LO Likelihood Ratio Test EE 7 NGN e EE 9 B
18. oom Hide Point Set Quantity 0 ccc ccc cece cence eee e ence cece eee eeees 108 PRU OM AL TE EE 108 pre en E e 108 Vill WSW WSYV Get Software Ready Software Setup Details WinSMITH Weibull WSW and WinSMITH Visual WSV are two different programs They have different installation diskettes Assume the installation diskette is placed in the A drive Assume the program will be setup into the C SMITHW directory the setup program will make this directory The programs are 32 bit Windows programs These more advanced programs will not run on the original Windows 3 0 or Windows 3 11 however they will run on all other higher level Windows systems including Windows 95 Windows 98 Windows ME Windows NT workstation or server Windows 2000 workstation or server and Windows XL RAM requirements are modest and space required on the hard drive is also modest Note to LAN managers perform the entire setup on the machine you intend to use do not set it up on one machine and copy the files to another machine as the installation program adds programs to the systems directories For each program run its SETUP EXE file on the diskette provided From Windows select START and then RUN and enter A SETUP EXE after the path locating SETUP EXE Or you can use BROWSE to locate SETUP EXE on the disk then run the SETUP EXE program Follow the on screen instructions given during SETUP Starting Instructions Start the software from the main Wi
19. orecast 6334 9 7062 8 7806 0 8564 0 9335 0 10119 3 Lambda Beta r 2 0 01 0 8 1 1 000 Time Total Cumulative Figure V9 WinSMITH Visual Crow AMSAA Cumulative Failure Forecast Click on Option E under the C A icon will show the failure trends for the graph in Figure V7 into the future which is the basis for a fearless forecast about failures which will occur unless action is taken to correct the trend line The extrapolated line is shown in Figure V9 Remember for Figure V9 the plot will always increase upward with more failures and the best you can hope for is a significant improve ment which would incur large intervals between failures which would cause the line to break sideways If the trend line for Figure V9 moves upward rapidly it signifies bad news with deteriorating reliability and more failure s coming faster which is an unhappy situation Crow AMSAA Plot Crow rgr Lambda Beta r 2 0 01 0 8 1 1000 Time Total Cumulative Figure V10 WinSMITH Visual Crow AMSAA Cumulative MTBF Plot Clicking on Option T under the C A icon transforms the Y axis from cumulative failures to cum failures cum time For this case of beta lt 1 the trend line will point upward the desired direction as shown in Figure V10 Option T s transform will allow he trend line to point upward or downward as indicated by the happy sad faces When no improvements occur
20. ration files into path XXX Add tYYY for temporary file storage location as path YYY Include a space between entries Please see the HELP file in the software for more command line examples Getting Started After Software Is Loaded Here are a couple of tips about the appearance of the software differences For WinSMITH Weibull the probability plotting and analysis software refer to Figure 1 lt WinSMITH TM Weibull 4 0N 32 gt ST AE EP _NU Options Weibull la xi Note the software version is numeric the Paint 3 revision is indicated by a alpha character and Point5 32 indicates the software is a 32 bit system Note the software name is WinSMITH Weibull 4 Figure 1 WinSMITH Weibull Figure 2 shows the icons for WinSMITH Weibull WSW Eeer Kee fee We Fle E Edi _ _ D ftiong A_ Analysis B To ls__ H Aelp_ Weibull HA Clee Ed SSES About lt F2 gt Figure 2 WinSMITH Weibull Icon Definitions Look at the differences for WinSMITH Visual the general scientific graphing and Crow AMSAA plotting software refer to Figure 2 Notice the name Visual and fewer icons than for WinSMITH Weibull ff NEN lt WINSMITH TS Visual 4 0N 32 gt revision is indicated by a alpha character and 32 indicates the software is a 32 bit system Point2 Point3 Point4 PointS Point6 Point9 4 Figure 3 WinSMITH Visual Figure 4 shows t
21. the line will move horizontal The third option frequently used for display of reliability growth involves the instantaneous failure rate which is obtained from Option T along with Option I for the instantaneous trend line The instantaneous line and the MTBF line will be concurrent if the condition of no change beta 1 occurs however if beta lt 1 the instantaneous line will lie above the MTBF trend line and likewise if beta gt 1 the instantaneous trend line will lie below the MTBF line The transformed MTBF line and the instantaneous trend line are shown in Figure V11 Page 22 Click Results Minimize l l In Figure NI p AMSAA projecting the trend line Crow S Plot downward and to the left Crow rgr a 1 will show that at time 1 8 E r SE on the log scale the trend i e i d Se INS 1 Tine will cross 100 which i EE is equivalent to A 0 01 for the failure rate Also since the system is improving the instant taneous failure rate 1s also growing as displayed above the MTBF trend line 1000 MT 3 E ee SSE The faster the growth in 0 01 0 8 1 arr reliability the greater is 100 1000 10000 the involvement by the development team to introduce improvements and to keep them in place SO the instantaneous failure rate plot clearly shows growth opportunities the gap between the lines derived from making improvements 10 Tame Total Cumulative FF Figure V11 WinSMITH Visual Crow AMSAA Cumulative MT
22. ty Datum Suspension The reminder dialog box is shown in Figure W8 WSW ar A er re Weibull la gt Data Format Datum x Format Datum x Quantity Datum eg Data __ NewSet___ __ Mouse pointer and tooltip reminder box Point pointe about data format The memory jogger says Point4 the data must be in Datum age x Quantity Points i Pont number of observations If the age is a suspension it must be preceded by a minus sign to signify a Suspension or censored data 4 Figure W8 WinSMITH Weibull Tooltip Reminder Box End of the excerpts from the training manual Page 16 WinSMITH Visual Software Excerpts From The Manual 1 Manual Data Input The spreadsheet becomes active when you click in the sheet just like occurs with Excel and it changes appearance to give you clues the sheet the sheet is active as shown in Figure V1 Delete cell s 1 Click in spreadsheet Cut data cell s 2 Enter data here Copy cell s Full screen 3 Press the Enter key Paste data spreadsheet Co Se Data New Set New Set E Accept data entry Spreadsheet before click Spreadsheet after click Figure V1 WinSMITH Visual Spreadsheet Data is enter into the plotting software in the format X scale Y scale Quantity the quantity feature is also used for a Z scale 3 dimensional plot when the quantity is not specified then the default value of 1 is supplied by the software Unlike t
23. uantity in widely separate columns Multiple columns can be consolidated into a single column for insertion into WinSMITH Weibull using Excel s CONCATENATE function Use the Excel consolidation function concatenate to produce a 1 column of data in Excel Highlight the Excel data and copy to the clipboard Insert the consolidated data into WinSMITH Weibull via the paste icon Data in column AA in the Excel spreadsheet IS Age Quantity for import as a single The Excel consolidation function column of data for in column AA is pasting directly into concatenate c1 Toi WinSMITH the text function tells Excel Weibull the information is not a math function but rather a text symbol Figure W7 WinSMITH Weibull Data Imported From Excel eee una Ee consolidation function involves use of the amp operator for concatenation For example concatenate cl ql in Figure W7 is equivalent to c1 amp amp ql1 where the parentheses are optional with the amp operator but are shown here for clarity just as might occur for clarity in an Excel spreadsheet The concatenation function works well when many columns of data must be imported into WinSMITH Weibull as columns of frequency data Datum x Quantity Page 15 6 Data Entry Reminder When the mouse pointer is on the spreadsheet a dialog box appears as a reminder concerning data format The dialog tells you the data should be in the format of Data x Quanti
24. umn of data paste icon click the usual Windows in Excel and paste command does not function copy to clipboard because of the frequency table format e Data E ETES D Poiti 4 an Spreadsheet after clicking paste icon Figure W5 WinSMITH Weibull Data Import From Excel The pasted results will look like the data shown in the right hand side of Figure W5 Page 14 5 How To Import Two Column Data From Excel With Suspensions In Excel make sure the left hand column contains age to failure and the right hand column contains the quantity number of occurrences of data Copy the data from Excel and paste into WinSMITH Weibull using the paste icon then the WinSMITH Weibull software will recognize the data requires some decisions and select the option that the two column data has quantities in the right hand using Option B to get the data shown in Figure W6 Figure W6 has Step 1 Step 2 suspended or censored data as Highlight Excel Paste data by use of the paste 2 col q i i evidenced by the column data Icon and choose option B er minus den and copy see note in Figure 9 in Excel which e x translates to the gt fi A B sign as shown in 1 Age To Failure Quantity Point JC Figure W6 Thus He WinSMITH automatically put Weibull handles the into rank order conversions automatically Complicated spreadsheets may Figure W6 WinSMITH Weibull Data 2 lmport From Excel have age and q
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