1. Worksheet Descriptions
Six Sigma Simulation
Data Definitions
and
Worksheet Descriptions

2. Six Sigma Data Definitions
Overview
The purpose of this presentation is to:
Define the purpose and data contained on each Excel SixSigma-2 worksheets
Define the inter-relationships between the worksheets
Briefly describe the simulation output for a Design of Experiments (DOE)
8/6/2004
Six Sigma Data Definitions

3. Six Sigma Data Definitions
Worksheets
The simulation output is contained on the following 8 worksheets:
Data - cycle time and quality (defect and defective) data for each of the three operations
Automatic Component Insertion (ACI)
Manual Assembly (MA)
Solder
Analysis – aggregate data and basic cost statistics
Hidden Cost – various yield measurements and hidden cost information
Defect – summarized data for type & frequency of defects and number of defective units
Chart1, Chart2, Chart3 – I-MR & P-charts for each operation
CumData – similar information to the Data worksheet plus subgroup totals
8/6/2004
Six Sigma Data Definitions

4. Six Sigma Simulation Screenshot
8/6/2004
Six Sigma Data Definitions

5. Automatic Component Insertion
Defect Definitions
Automatic Component Insertion
Y1: Epoxy Contamination
Y2: Tuner Misalignment
Y3: Missing/Wrong Parts
Y4: Lead Length
Y5: Bad Assembly
Y6: Chip Skew
Manual Assembly
Y1: Reversed Parts
Y2: Wrong Parts
Y3: Leg-Outs
Y4: Shortened Leads
Y5: Incorrect Rework
Y6: Missing Parts
Solder
Y1: Missing Solder
Y2: Glue Contamination
Y3: Solder Bridge
Y4: Insufficient Solder
Y5: Solder Composition
Y6: Others
8/6/2004
Six Sigma Data Definitions

6. Data Worksheet Overview
This worksheet presents quality results for each processed unit (PCB) at each of the three operations
Start and End Time
Total Index – The overall quality rating for the PCB
Component Measure – The number of defects for each of the six defect types
Component Index – A quality rating for each of the defect types. The PCB design allows for a predetermined number of defects before a board is either reworked or scrapped
The data on this worksheet is volatile – i.e., it is cleared prior to the subsequent simulation run.
8/6/2004
Six Sigma Data Definitions

7. Data Worksheet Screenshot
The Data worksheet contains similar sections for the remaining two operations – Manual Assembly (MA) and Solder.
8/6/2004
Six Sigma Data Definitions

8. Six Sigma Data Definitions
Material Flow Process
Parts at mfg
station
(new or rework)?
Manufacture
next PCB
PCB
acceptable?
Scrap part
Yes
Send PCB to
next operation
or ship
finished product No
scrap?
Parts at
queue?
Pull material
from queue
Send PCB back
to mfg process
for rework
Pull parts
from raw material
Start
Correct arrow for rework line back to process instead of start block
8/6/2004
Six Sigma Data Definitions

9. Raw Material Shipment Example
A RM kit is shipped at time = 0 to start the process. The first unit processed requires rework (Total Index = 2).
Since there is no material in the queue prior to the next process operation, a RM kit is pulled into the queue to await processing (shipped at t = 4.22).
The second RM kit shipped sits in the queue until the unit being reworked is either completed or scrapped.
The first unit completes rework and is accepted at t = 8.41.
The RM in the queue (second RM shipped) moves into the ACI process at t = 8.41.
At t = the second unit is completed and the third RM kit is shipped directly to the queue and into the ACI process.
Data Worksheet
Need to identify total index 1, 2, 3 before its use on this slide
8/6/2004
Six Sigma Data Definitions

10. Six Sigma Data Definitions
Cycle Time
Data Worksheet
CumData Worksheet
Cycle Time for each processed unit can be determined from the start and end times on the Data worksheet for each operation by subtracting the start time from the end time for each RM unit (there may be some rounding discrepancies).
8/6/2004
Six Sigma Data Definitions

11. Data Worksheet - Quality Index
There are three main, identical sections for each operation containing information on process quality:
Total Index – The “final” inspection result for the processed PCB. A good PCB is denoted by “1”, a PCB requiring rework is denoted by “2”, and a scrapped PCB is denoted by “3”.
Component Measure – Quantitative results for process quality broken down by defect type (Y1 – Y6). These columns, with the exception of ACI defect type Y2, contain the count for the number of defects introduced for each unit processed. (ACI defect type Y2 data is the distance the tuner is off its target).
Component Index – A qualitative quality measurement. The six columns provide the results for each of the defect types.
8/6/2004
Six Sigma Data Definitions

12. Data Worksheet - Interpretation
Total Index Results:
The PCB must be reworked (Index = 2).
Component Measure Results:
The Tuner Misalignment (Y2) was 8.98 mm (acceptable at ≤ 20) and there was one Missing / Wrong Part (Y3) which required the PCB to be reworked.
Component Index Results:
The quality was “Good” (index = 1) for all defect types except Y3 (index = 2).
8/6/2004
Six Sigma Data Definitions

13. Data Worksheet - Interpretation
Material Flow Example:
On its first pass, the highlighted board fails quality inspection due to a Y4 (length of leads) defect type and is sent back for rework.
On the second pass through the process, it fails a second time due to a Y4 defect, but also due to a newly introduced Y3 (missing / wrong parts) defect type.
On the third pass through the process, these defects are corrected, however, a Y5 (bad assembly) defect type is caught at inspection.
Finally, on the fourth pass through the system, the PCB passed quality inspection.
8/6/2004
Six Sigma Data Definitions

14. Data Worksheet - Interpretation
In this case the system was set up to produce (a lot of) bad parts.
The system did not produce a single non-defective PCB (all Total Index results are “2”)
There were a total of 200 “Y6” defect types. This total is captured in the Defect worksheet, but can be calculated from the Data worksheet as shown.
The number of reworked PCB’s, also captured on the Defect worksheet, can be calculated from the Data worksheet as shown.
The Tuner Misalignment (Y2) distance ranged from to A PCB requires rework if this distance exceeds 20. This fact is captured in the Component Index section for the 9th PCB processed.
Data Worksheet
=COUNTIF(entire Y6 column,2)
=SUM(entire Y6 column)
Defect Worksheet
8/6/2004
Six Sigma Data Definitions

15. Six Sigma Data Definitions
Analysis Worksheet
This worksheet is divided into two sections, Input and Results
Input
Collects totals from the Data worksheet for number of units processed, plus scrap and rework
Details amount and location of WIP in the system at the end of the production run
Results
Calculates yields, process costs, and cycle times for each operation
Determines overall raw material, process, and scrap costs per good unit
Presents the cycle time per good unit and its standard deviation
8/6/2004
Six Sigma Data Definitions

16. Analysis Worksheet – Input Section
RM shipped prior to completing order (in this case 200)
PCB’s requiring no rework
The Solder operation was able to process all 200 units produced by the MA process, even while reworking 89 units, due to its shorter CT.
Total number of PCB’s processed by ACI, including good PCB’s, and those reworked (possibly more than once), and scrapped. This is the final entry in the “Process Unit” column on the “Data” worksheet.
Input Algebra (Solder):
289 PCB’s processed
- 200 Total good PCB’s
89 # of PCB’s needing rework
Recycled PCB’s
29 PCB’s reworked more than once
8/6/2004
Six Sigma Data Definitions

17. Analysis Worksheet – Input Section
Interpreting the Output: Why are the capacity utilizations at 100% for ACI and MA and not Solder?
ACI: With its shorter CT (relative to the MA operation) the ACI process continues to push all of its completed units to the buffer/queue in front of the MA operation.
MA: In this instance the MA operation is the bottleneck.
Solder: Must wait for units from the MA operation due to MA’s greater CT
The cost parameters are fixed
Data pulled from simulation
Time required to complete entire order
8/6/2004
Six Sigma Data Definitions

18. Analysis Worksheet – Results Section
Calculations for each of the above metrics are covered on following slides
8/6/2004
Six Sigma Data Definitions

19. Results Calculations - Yields
Similar calculations will determine MA and Solder yields
8/6/2004
Six Sigma Data Definitions

20. Results Calculations - Process
For
ACI
Process
8/6/2004
Six Sigma Data Definitions

21. Results Calculations - Overall Costs
8/6/2004
Six Sigma Data Definitions

22. Hidden Cost Worksheet - Yields
Yield Definitions:
1st Quality / Input: How many good units were made by the process given the amount of raw material or good units supplied by the prior process?
1st Quality – 1st Time / Input: How many good units were processed on their first pass through the operation?
1st Quality / Throughput: Accounts for the impact of reworked units by looking at the total number of units processed by the operation – versus the quantity of raw material or units delivered to the process.
1st Quality – 1st Time / Throughput: Of the total number of units processed by the operation, what percentage were produced defect-free on their first pass through the operation?
8/6/2004
Six Sigma Data Definitions

23. Hidden Costs – Yield Calculations
For the MA and Solder operations, the denominator is the total good units processed from the prior step – in this case, MA would use “369” from the ACI column.
Hidden Cost Worksheet
Analysis Worksheet
8/6/2004
Six Sigma Data Definitions

24. Hidden Costs – Yield Calculations
8/6/2004
Six Sigma Data Definitions

25. Hidden Costs – Yield Calculations
8/6/2004
Six Sigma Data Definitions

26. Hidden Costs – Yield Calculations
8/6/2004
Six Sigma Data Definitions

27. Hidden Costs – Factory Calculations
From earlier calculations
8/6/2004
Six Sigma Data Definitions

28. Six Sigma Data Definitions
Defect Worksheet
The Defect worksheet presents the final results by defect-type for the latest simulation run.
NOTE: A defective PCB may have more than one type of defect. Furthermore, a defective PCB may also have more than one occurrence of the same defect type.
In this case:
The ACI operation processed 539 PCB’s. (This total will agree with the “Units Processed” field on the Analysis worksheet)
For the ACI operation, 511 units were “good” or non-defective with respect to defect type “Y1”. The remaining 28 units had a total of 29 Y1 defects (i.e., one PCB had two Y1 defects).
Similarly, of the 278 units processed by the MA operation, there were 27 defective PCB’s that required rework due to defect type Y1 (note there were 31 total type Y1 defects)
8/6/2004
Six Sigma Data Definitions

29. Six Sigma Data Definitions
Chart Worksheets
The following control charts are presented for completeness in covering the Excel simulation data file.
Discussion on the use and application of control charts is beyond the scope of this presentation. There are many excellent sources of information on this subject; “Statistical Quality Control, Strategies and Tools for Continual Improvement” by Johannes Ledolter and Claude W. Burrill is recommended, as is “Statistical Quality Control” by Eugene L. Grant and Richard S. Leavenworth.
8/6/2004
Six Sigma Data Definitions

30. Six Sigma Data Definitions
Chart Worksheets
8/6/2004
Six Sigma Data Definitions

31. Six Sigma Data Definitions
Chart Worksheets
8/6/2004
Six Sigma Data Definitions

32. Six Sigma Data Definitions
CumData Worksheet
This worksheet presents the same basic information as the Data worksheet, but with a few significant differences:
The data on this worksheet is maintained, unless otherwise intentionally cleared, during multiple simulation runs. This allows data to be captured and saved during a series of DOE simulation runs.
This worksheet contains subgroup data. The subgroup size defaults to 10 units and can be manually changed in the Extend simulation.
The cycle time for each processed unit is reported – versus the start and stop times in the Data worksheet
The data contained in the component measure (ACI-CM-Y#) and component index (ACI-CI-Y#) columns are identical to the Data worksheet.
8/6/2004
Six Sigma Data Definitions

33. CumData Worksheet Sections
The data on this worksheet is presented in a similar format to that on the Data worksheet…
… A section containing the number of defects by defect type for each operation…
… A section indicating the quality index (need for rework or scrap) by each defect type…
… And a section containing the number of defective units per defined subgroup size due to each defect type .
8/6/2004
Six Sigma Data Definitions

34. CumData Worksheet - Subgroups
An inspection of columns “B” through “O” will show the data is identical to that on the Data worksheet.
The subgroup size, which is defined in the Extend simulation, was left at the default size of 10.
The subgroup data (columns “Q” through “W”) for the final subgroup will not be completed any time the simulation run is either:
Stopped prior to producing a complete subgroup or,
The defined number of units are some fraction of the subgroup (e.g., a run size of 78 with a subgroup size of 10)
8/6/2004
Six Sigma Data Definitions

35. CumData Worksheet - Subgroups
NOD = Number of Defectives
The sum of the number of defective units for the subgroup (column “C”) is shown in column “Q” (ACI-TQ-NOD)
Likewise, the totals for the number of defective units per defect type are shown in columns “R” through “W”
As on the Data worksheet, multiple defect types on a single unit may contribute to the unit being identified as defective (e.g., second unit in the subgroup, Row 13)
8/6/2004
Six Sigma Data Definitions

36. Design of Experiments (DOE)
The CumData worksheet contains all of the data needed to analyze the results of a DOE
To conduct a DOE you will need to set the “Number of Units to Produce” button to “1”
Do not click the “Send Command” button – this will erase all CumData worksheet information for the prior runs
8/6/2004
Six Sigma Data Definitions

37. Six Sigma Data Definitions
DOE – ACI Output
This screenshot shows the results of ten consecutive runs. Each simulation run is set to terminate after processing one unit, regardless of whether the unit was good, required reworked, or was scrapped. Each simulation run, as in a DOE, had different factor settings.
The “run number” is captured in column “A” – this number will correspond with the run order assigned to the DOE in Minitab.
In performing a DOE, each simulation run processes a “new” unit. Thus, one cannot deduce how many process cycles it took to produce a good unit by examining the ACI-TQI data.
Columns A through W should be copied into Minitab to analyze the DOE results (Similar steps will be taken to analyze the Manual Assembly and Solder processes).
8/6/2004
Six Sigma Data Definitions