04/14/231 04/14/231
Project Name : Black Belt Project for improving Reaction Force
Project Owner : Dipti Nayak
DMAIC
04/14/232
Define
1. Map the Project2. Project Charter3. Terms and Acronyms Used4. ARMI & Communication Plan5. RASIC Model6. Details process map7. SIPOC
04/14/233
Customer Sample CommentsKey Output Characteristics
Important to Customer (CTQ's)
Compressor Assy.
Area in charge
During the working of the AC cycle
improper clutching & clutch noise
observe in model-A compressor.
Improper reaction Force.
Due to improper clutching & clutch
noise customer complaints & line
rejection PPM has been increased too
much.
Customer complaints &
Line Rejection PPM.
DefineMap the Project
04/14/234
In Scope: : This Project is for Compressor Model A HUB Line .
Out of Scope: All other models & Lines..
Business Case: ABC Ltd is a leading car AC manufacturing company of India & Located in Gurgaon.
Since last couple of month it has been observed that customer complaints & Line rejection PPM has been increased due to improper clutching & clutch noise in
model-A compressor .Due to which line rejection PPM has been increased & customer is very much dissatisfied
& company is also loosing revenue.
Problem Statement: It has been observed that since Jan-13 month due to improper reaction force in M-A hub assy. Customer complaints for improper clutching & clutch noise has been exceed the target 0 & reached up to 6 no's & hub assy line rejection PPM has been exceeds the target 1000 ppm & reached till 8526 ppm . Due to this repeating problem, production for the same model is hampering too much & customer is very much dissatisfied due to repeated complaints & also company is loosing their revenue & business.
Goal Statement: The goal of this project will be to eliminate the improper clutching & clutch noise problem by improving the reaction force & hence reduce the customer complaint up to the target 0 & line rejection PPM within target 1000 ppm by 20th June-13.
Project Charter
Start Date End Date
Define 10.03.13 31.03.13
Measure 1.03.13 15.04.13
Analyze 16.04.13 16.05.13
Improve 17.05.13 31.05.13
Control 1.06.13 20.06.13
High Level Project Plan
Define
04/14/235
Definitions:
Indicators Definition
PPM Part per million opportunity
DPMO Defect per million opportunity
DPO Defect per opportunity
mm Millimeter
Terms and Acronyms Used Define
04/14/236
Key Stakeholders Define Measure Analyze Improve Control
Sponsor- CEO A/I A/I A/I A/I A/I
Champion-SGM R/I R/I R/I R/I R/I
MBB A/I A/I A/I A/I A/I
BB M M M M M
GB M M M M M
Team Members R R R R R
Message Audience Media Who When
Project Status Leadership E-mails Black Belt Weekly Basis
Project Review GB,BB,MBB & Champion
E-mails or Meetings Black Belt As per Project Plan
Project Deliverables or Activities
Members Emails, Meetings Black Belt Weekly
When Populating the Stakeholder, consider the ARMI:• A= Approver of team decisions• R= Resource or subject matter expert (ad hoc)• M= Member of team• I= Interested Party who will need to be kept informed
Communication PlanCommunication Plan
Define
ARMI WorksheetARMI WorksheetARMI & Communication Plan
04/14/237
DefineRASIC Chart
04/14/238
Details Process Flow Diagram Define
04/14/239
XYZ (supplier)
NA
NA
NA
NA
Hub, rivet, armature, spring plate, washer
Hub Sub, Assy
Hub Sub Assy-2
Hub Assy
Hub Assy
Hub Riveting
Hub Grinding
Reaction Force testing
Hub balancing
Slip Torque Testing
Hub Sub Assy-1
Hub Sub Assy-2
Hub Assy
Hub Assy
Hub Assy
Compressor assy. line
Compressor assy. line
Compressor assy. line
Compressor assy. line
Compressor assy. line
DefineProcess Map
04/14/2310
Measure
1. Data Collection Plan2. Measurement System Analysis3. Process Capability
04/14/2311
Y OperationalDefinition
DefectDefinition
PerformanceStandard
Specification Limit
Opportunity
Improper Reaction force
Reaction force is the load required to
deflect the hub by 0.5 mm with respect
to outer armature when load is applied
centrally on hub surface.
Sticking of Hub with Rotor due to less Reaction force.
Reaction force should lie between 90~130 N
within 0.5mm deflection.
LSL= 90N & USL=130N
10 Pcs/shift
Mode of collecting Data
Y Data Type UnitDecimal to
be Used
Data Base Container
Existing or new data
base
If New when data base would be
ready.
Plan start date for
DCP
Improper Reaction force Variable mm, Newton
Max up to three placed. Excel sheet Existing
-
-
Data Collection Plan
Equipment Used for
measurement
Equipment Calibration Information
ResponsibilityAny
Training need
Operator Information
Vernier caliper Equipment was calibrated with
Bharti automation on
dated 10.09.12.
Line QA in charge
-
-
-
-
-
Measure
04/14/2312
Measurement System Analysis Measure
04/14/2313
% Tolerance = 9.01
Number of Distinct Categories = 15.59
%Contribution
KPI Data Type
GRR% ≤ 10
NDC ≥ 5Continuous
APPRISER - A APPRISER - B APPRISER - C
CONCLUSION: As per MSA study carried out we get GRR%= 9.01 & NDC=15.59 which satisfy the AIAG Requirement (GRR% ≤ 10, NDC ≥ 5). It shows that our Measurement
System is good enough for measuring the variation of the measurement System.
13
Measurement System Analysis Measure
04/14/2314
Measurement System Analysis Measure
04/14/2315
Measurement System Analysis
Rule Rule Description Acceptable Result
A R&R % of Tolerance <10% 9.01
B% Contribution (R&R Std deviation)
Smaller than Part-to-part variance
99.59
C Number of distinct categories >4 15.59
Overall Gage result- Measurement system is accepectable for taking measurement.
Measure
04/14/2316
Process Capability for current Reaction force Measure
Current process is incapable since current process potential capability & actual capability are 0.80 & 0.63 respectively & which is not acceptable as per AIAG guideline.
Current process potential performance & actual performance are 0.51 & 0.40 respectively Which is also not acceptable as per AIAG guideline.
Current process is unstable & also not in statistical control.
04/14/2317
Current process is not acceptable as long term process capability (ZLT) is 1.06 & short term process capability (ZST) is only 2.56 .
Current process is also unstable & also not in statistical control.
The current process PPM has been exceeds the current PPM target 1000 & has been reached till PPM 8526.31.
Z-Value & PPM for current process Measure
04/14/2318
MeasureDefect Pareto in Hub assy. Area During Feb-13 to April-13 Month
Six sigma project has been started to eliminate the same.
CFT is working on the same.
04/14/2319
MeasureModel wise defect in Hub assy. Area During Feb-13 to April-13 Month
04/14/2320
1. DCP for Potential Xs2. Identify Potential Xs3. DCP for Potential Xs4. Basic Analysis for Project Y5. Checking for Impact of ...... on Y6. Hypothesis Summary7. MSA results of Impacting Factors
Analyse
04/14/2321
Identify Potential Xs Analyse
04/14/2322
DCP for Potential Xs
Potential Cause Type of Data Collection Method
Test to be Used Visualization plot Used
Washer thickness Continuous Check sheet Co-relation & Regression
Scatter plot
Hub run out Continuous Check sheet Co-relation & Regression
Scatter plot
Rivet height Continuous Check sheet Co-relation & Regression
Scatter plot
Rivet dia. Continuous Check sheet Co-relation & Regression
Scatter plot
Spring plate dimple dimension
Continuous Check sheet Co-relation & Regression
Scatter plot
Flatness of hub assy. Continuous Check sheet Co-relation & Regression
Scatter plot
Grinding surface concavity
Continuous Check sheet Co-relation & Regression
Scatter plot
Armature surface flatness
Continuous Check sheet Co-relation & Regression
Scatter plot
Analyse
04/14/2323
Basic Analysis of Project YRandomness Study Randomness Study
Analyse
As per run chart we can see that process is unstable since there are clustering & trends in given data set.
P value for clustering & trend is also less than 0.05. (P value <0.05)
While P-value for Mixtures & oscillation >0.05.
04/14/2324
Basic Analysis of Project Y
Normality StudyNormality Study
Analyse
Anderson Darling test for reaction force shows that data is non-normal ,since data points are not falling on straight line & P-value is less than 0.05.
P-Value < 0.005 .
04/14/2325
Normal Graphical Plot Measure
Reaction force data is non-normal , since mean & median is not coinciding & data point is also not symmetrical about the mean & P-value is less than 0.05.
P-value < 0.005
Data variation is also too much since standard deviation is 13.05.
Central Tendency & spread studyCentral Tendency & spread study
04/14/2326
Basic Analysis of Project Y
Frequency distribution of Reaction force Frequency distribution of Reaction force
Analyse
Data for reaction force is not showing the central tendency & data is also showing too much variation. Some data points are also falling out side lower specification limit .
04/14/2327
Graphical DepictionGraphical Depiction Hypothesis Result Hypothesis Result
Inference : There is a strong positive co-relation between reaction force & washer thickness since Pearson coefficient e = 0.882 & p value is 0.000 (< 0.05) & as per Regression test R-Sq is more than 62% , Hence there is a significant impact of washer thickness on reaction force.
Inference : There is a strong positive co-relation between reaction force & washer thickness since Pearson coefficient e = 0.882 & p value is 0.000 (< 0.05) & as per Regression test R-Sq is more than 62% , Hence there is a significant impact of washer thickness on reaction force.
Checking for Impact of Washer Thickness on Reaction force Analyse
Correlations: Reaction force vs. Washer thickness
Pearson correlation of Reaction force and Washer thickness = 0.882P-Value = 0.000
Regression Test : RS = 6.19062 R-Sq = 77.7% R-Sq(adj) = 77.5%
04/14/2328
Graphical DepictionGraphical Depiction Hypothesis Result Hypothesis Result
Checking for Impact of Dimple dimension on Reaction force Analyse
Corelations: Reaction force vs Dimple dimension
Pearson correlation of Reaction force and Dimple dimension = -0.194P-Value = 0.053
Regression Test : S = 12.8664 R-Sq = 3.8% Sq(adj) = 2.8%
Inference : Since P-Value is 0.053(>0.05) so there is no significant co-relation between reaction force & dimple dimension & as per Regression test also R-Sq is 3.8% (<62% ) ,Hence there is also no significant impact of dimple dimension on reaction force.
Inference : Since P-Value is 0.053(>0.05) so there is no significant co-relation between reaction force & dimple dimension & as per Regression test also R-Sq is 3.8% (<62% ) ,Hence there is also no significant impact of dimple dimension on reaction force.
04/14/2329
Graphical DepictionGraphical Depiction Hypothesis Result Hypothesis Result
Checking for Impact of Armature flatness on Reaction force
Inference : Since P-Value is 0.095 (>0.05) so there is no significant co-relation between reaction force & armature flatness & as per Regression test also R-Sq is 2.8% (<62% ) ,Hence there is no significant impact of armature flatness, on reaction force.
Inference : Since P-Value is 0.095 (>0.05) so there is no significant co-relation between reaction force & armature flatness & as per Regression test also R-Sq is 2.8% (<62% ) ,Hence there is no significant impact of armature flatness, on reaction force.
Analyse
Correlations: Reaction force, Armature flatness
Pearson correlation of Reaction force and Armature flatness = -0.168P-Value = 0.095
Regression Test- S = 12.9286 R-Sq = 2.8% R-Sq(adj) = 1.8%
04/14/2330
Graphical DepictionGraphical Depiction Hypothesis Result Hypothesis Result
Inference : Since P-Value is 0.115 (>0.05) so there is no significant co-relation between reaction force & flatness of hub assy & as per Regression test also R-Sq is 1.3% (<62% ) , Hence there is no significant impact of flatness of hub assy on reaction force.
Inference : Since P-Value is 0.115 (>0.05) so there is no significant co-relation between reaction force & flatness of hub assy & as per Regression test also R-Sq is 1.3% (<62% ) , Hence there is no significant impact of flatness of hub assy on reaction force.
Checking for Impact of flatness of Hub assy.on Reaction force Analyse
Correlations: Reaction force, Flatness of hub assy.
Pearson correlation of Reaction force and Flatness of hub assy. = 0.115P-Value = 0.256
Regression Test - S = 13.0284 R-Sq = 1.3% R-Sq(adj) = 0.3%
04/14/2331
Graphical DepictionGraphical Depiction Hypothesis Result Hypothesis Result
Inference : Since P-Value is 0.469(>0.05) so there is no significant co-relation between reaction force & grinding surface concavity & as per Regression test also R-Sq is o.5 % (<62% ) , Hence there is no significant impact of grinding surface concavity of on reaction force.
Inference : Since P-Value is 0.469(>0.05) so there is no significant co-relation between reaction force & grinding surface concavity & as per Regression test also R-Sq is o.5 % (<62% ) , Hence there is no significant impact of grinding surface concavity of on reaction force.
Checking for Impact of Concavity on Reaction force Analyse
Correlations: Reaction force, Grinding surface concavity
Pearson correlation of Reaction force and Grinding surface concavity = 0.073P-Value = 0.469
Regression Test - S = 13.0797 R-Sq = 0.5% R-Sq(adj) = 0.0%
04/14/2332
Graphical DepictionGraphical Depiction Hypothesis ResultHypothesis Result
Inference : Since P-Value is 0.593(>0.05) so there is no significant co-relation between reaction force & Rivet height& as per Regression test also R-Sq is 0.3% (<62% ) , Hence there is no significant impact of Rivet height on reaction force.
Inference : Since P-Value is 0.593(>0.05) so there is no significant co-relation between reaction force & Rivet height& as per Regression test also R-Sq is 0.3% (<62% ) , Hence there is no significant impact of Rivet height on reaction force.
Checking for Impact of Rivet Height on Reaction force Analyse
Correlations: Reaction force, Revit height
Pearson correlation of Reaction force and Revit height = 0.054P-Value = 0.593
Regression Test - S = 13.0957 R-Sq = 0.3% R-Sq(adj) = 0.0%
04/14/2333
Graphical Depiction
Graphical Depiction
Hypothesis Result Hypothesis Result
Inference : Since P-Value is 0.171(>0.05) so there is no significant co-relation between reaction force & Rivet dia & as per Regression test also R-Sq is 1.9% (<62% ) , Hence there is no significant impact of Rivet dia on reaction force.
Inference : Since P-Value is 0.171(>0.05) so there is no significant co-relation between reaction force & Rivet dia & as per Regression test also R-Sq is 1.9% (<62% ) , Hence there is no significant impact of Rivet dia on reaction force.
Checking for Impact of Rivet dia on Reaction force Analyse
Correlations: Reaction force, Revit dia
Pearson correlation of Reaction force and Revit dia = 0.138P-Value = 0.171
Regression Test - S = 12.9892 R-Sq = 1.9% R-Sq(adj) = 0.9%
04/14/2334
Graphical DepictionGraphical Depiction Hypothesis Result Hypothesis Result
Inference : Since P-Value is 0.234(>0.05) so there is no significant co-relation between reaction force & Hub run out & as per Regression test also R-Sq is 1.4% (<62% ) , Hence there is no significant impact of Hub run out on reaction force.
Inference : Since P-Value is 0.234(>0.05) so there is no significant co-relation between reaction force & Hub run out & as per Regression test also R-Sq is 1.4% (<62% ) , Hence there is no significant impact of Hub run out on reaction force.
Checking for Impact of Hub Run out on Reaction force Analyse
Correlations: Reaction force, Hub run out
Pearson correlation of Reaction force and Hub run out = 0.120P-Value = 0.234
Regression Test - S = 13.0198 R-Sq = 1.4% R-Sq(adj) = 0.4%
04/14/2335
Checking for Impact of other Potential cause on Reaction force Analyse
04/14/2336
Hypothesis SummarySl. No. Factor P Value
Graphical Tool Used
Inference Next Steps
1 Washer thickness 0.000 Scatter plotSignificant impact as R-Sq=77.5 % (R-Sq >62%)
100 pcs hub sub assembly need to done with washer having thickness higher side.
2 Dimple dimension 0.053Scatter plot Non-significant
impact (R-Sq <62%)N.A
3 Armature flatness 0.095 Scatter plotNon-significant impact (R-Sq <62%) N.A
4 Hub assy flatness 0.256Scatter plot Non-significant
impact (R-Sq <62%) N.A
5 Grinding surface concavity 0.469Scatter plot Non-significant
impact (R-Sq <62%) N.A
6 Rivet height 0.593Scatter plot Non-significant
impact (R-Sq <62%) N.A
7 Rivet dia 0.171Scatter plot Non-significant
impact (R-Sq <62%) N.A
8 Hub run out 0.234Scatter plot Non-significant
impact (R-Sq <62%) N.A
Analyse
04/14/2337
MSA Results of Impacting Factors
Sl. No. FactorMSA
Method Used
ResultRCA for Problems
Next Steps
1 Washer thicknessANOVA Method
Pass (% R&R <9.01)
Analyse
04/14/2338
Improve
1. Screening of the Impacting Factors2. Action Plan for Improving the Factors3. Basic Analysis of Improved Y4. Pre–Post Analysis of Project Y5. Pre-Post Analysis of Factor6. Improve Summary – Take Aways
04/14/2339
Improve
1. Screening of the Impacting Factors
High Medium Low
In Control (1)Washer Thickness -(2) Machine Load Cell Variation(3) Flatness of Resting fixture
Out of Control
Con
trol
Impact
04/14/2340
Screening of the Impacting Factors Improve
Step1- Take 30 pcs of washer thickness having range size of 1.44~1.50 & assembled with hub & Armature & made a hub assy.Step 2- Check the reaction force for this hub assy. Step 3- Made graphical summary for observed reaction force to see the variation & central tendency of the data.Step 4- Also draw histogram to understand the frequency distribution of reaction force.Step5- Do normality plot of observed reaction force to understand the normal behaviour of the reaction force data.Step 6- Draw scatter plot to understand the nature of relationship between reaction force & washer thickness.
Trial -1,with washer thickness size 1.44~1.50.
04/14/2341
Screening of the Impacting Factors Improve
04/14/2342
Screening of the Impacting Factors Improve
Conclusion : When we take 30 pcs of washer thickness with range 1.44~1.50.We get improper reaction force. At this range most of the times reaction force get at lower side & some time it goes below specification limit .
Conclusion : When we take 30 pcs of washer thickness with range 1.44~1.50.We get improper reaction force. At this range most of the times reaction force get at lower side & some time it goes below specification limit .
Trial-1 , Take 30 pcs of washer thickness with range of 1.44~1.50
04/14/2343
Conclusion : 1. Normality test shows that the observed reaction force is non-normal since the P-value is less than 0.05 (P-value<0.05).2. Scatter plot Reaction force & washer thickness shows the positive relationship.
Conclusion : 1. Normality test shows that the observed reaction force is non-normal since the P-value is less than 0.05 (P-value<0.05).2. Scatter plot Reaction force & washer thickness shows the positive relationship.
Screening of the Impacting Factors Improve
04/14/2344
Trial conclusion- When we take the washer range 1.44 to1.50 mm ,we get improper reaction force i.e some time reaction force is below specification limit.However, by increasing the washer thickness, reaction force is also increasing.
Screening of the Impacting Factors Improve
04/14/2345
Screening of the Impacting Factors Improve
Trial -2,with washer thickness size 1.51~1.56 mm
Step1- Take 30 pcs of washer thickness having range size of 1.51~1.56 & assembled with hub & Armature & made a hub assy.Step 2- Check the reaction force for this hub assy. Step 3- Made graphical summary for observed reaction force to see the variation & central tendency of the data.Step 4- Also draw histogram to understand the frequency distribution of reaction force.Step5- Do normality plot of observed reaction force to understand the normal behaviour of the reaction force.Step 6- Draw scatter plot to understand the nature of relationship between reaction force & washer thickness.
04/14/2346
Screening of the Impacting Factors Improve
04/14/2347
Screening of the Impacting Factors Improve
Conclusion : When we take 30 pcs of washer thickness with range 1.51~1.56,We get reaction force at lower side of specification , the current date is non-centric, Conclusion : When we take 30 pcs of washer thickness with range 1.51~1.56,We get reaction force at lower side of specification , the current date is non-centric,
04/14/2348
Screening of the Impacting Factors Improve
Conclusion : The normality plot shows that current data set is non-normal since P-value is less than 0.05, 2. The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
Conclusion : The normality plot shows that current data set is non-normal since P-value is less than 0.05, 2. The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
04/14/2349
Screening of the Impacting Factors Improve
Trial conclusion- When we take the washer range 1.51 to1.56 mm ,we get reaction force lower side of specification.However, by increasing the washer thickness, reaction force is also increasing.
04/14/2350
Screening of the Impacting Factors Improve
Trial -3,with washer thickness size 1.56~1.63 mm.
Step1- Take 30 pcs of washer thickness having range size of 1.56~1.63 & assembled with hub & Armature & made a hub assy.Step 2- Check the reaction force for this hub assy. Step 3- Made graphical summary for observed reaction force to see the variation & central tendency of the data.Step 4- Also draw histogram to understand the frequency distribution of reaction force.Step5- Do normality plot of observed reaction force to understand the normal behaviour of the reaction force.Step 6- Draw scatter plot to understand the nature of relationship between reaction force & washer thickness.
04/14/2351
ImproveScreening of the Impacting Factors
04/14/2352
Screening of the Impacting Factors Improve
Conclusion : When we take 30 pcs of washer thickness with range size of 1.56~1.63 mm , We get that reaction force observed is below nominal value & process is left hand skewness.Conclusion : When we take 30 pcs of washer thickness with range size of 1.56~1.63 mm , We get that reaction force observed is below nominal value & process is left hand skewness.
04/14/2353
ImproveScreening of the Impacting Factors
Conclusion : 1.The normality plot shows that current data set is normal since P-value is greater than that 0.05, 2.The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
Conclusion : 1.The normality plot shows that current data set is normal since P-value is greater than that 0.05, 2.The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
04/14/2354
ImproveScreening of the Impacting Factors
Trial conclusion- When we take the washer range 1.56 to1.63 mm ,we get reaction force lower side of nominal value i.e less than 110 Newton.However, by increasing the washer thickness, reaction force is also increasing.
04/14/2355
Screening of the Impacting Factors Improve
Trial -4,with washer thickness size 1.64~1.70.
Step1- Take 30 pcs of washer thickness having range size of 1.64~1.70 mm & assembled with hub & Armature & made a hub assy.Step 2- Check the reaction force for this hub assy. Step 3- Made graphical summary for observed reaction force to see the variation & central tendency of the data.Step 4- Also draw histogram to understand the frequency distribution of reaction force.Step5- Do normality plot of observed reaction force to understand the normal behaviour of the reaction force.Step 6- Draw scatter plot to understand the nature of relationship between reaction force & washer thickness.
04/14/2356
Screening of the Impacting Factors Improve
04/14/2357
Screening of the Impacting Factors Improve
Conclusion : When we take 30 pcs of washer thickness with range size of 1.64~1.70 mm , We get that reaction force is falling around mean & also variation in data point is less.Conclusion : When we take 30 pcs of washer thickness with range size of 1.64~1.70 mm , We get that reaction force is falling around mean & also variation in data point is less.
04/14/2358
ImproveScreening of the Impacting Factors
Conclusion : 1.The normality plot shows that current data set is normal since P-value is greater than that 0.05 ( P-value>0.126)2.The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
Conclusion : 1.The normality plot shows that current data set is normal since P-value is greater than that 0.05 ( P-value>0.126)2.The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
04/14/2359
ImproveScreening of the Impacting Factors
Trial conclusion- When we take the washer range 1.64 to1.70mm ,we get reaction force is normally distributed around mean.However, by increasing the washer thickness, reaction force is also increasing.
04/14/2360
ImproveScreening of the Impacting Factors
Step1- Take 30 pcs of washer thickness having range size of 1.71~1.76 & assembled with hub & Armature & made a hub assy.Step 2- Check the reaction force for this hub assy. Step 3- Made graphical summary for observed reaction force to see the variation & central tendency of the data.Step 4- Also draw histogram to understand the frequency distribution of reaction force.Step5- Do normality plot of observed reaction force to understand the normal behaviour of the reaction force.Step 6- Draw scatter plot to understand the nature of relationship between reaction force & washer thickness.
Trial -5,with washer thickness size 1.71~1.76 mm
04/14/2361
ImproveScreening of the Impacting Factors
04/14/2362
Screening of the Impacting Factors Improve
Conclusion : When we take 30 pcs of washer thickness with range size of 1.70~1.76 mm , We get that reaction force are normally distributed as P-value is greater than 0.05.Conclusion : When we take 30 pcs of washer thickness with range size of 1.70~1.76 mm , We get that reaction force are normally distributed as P-value is greater than 0.05.
04/14/2363
Screening of the Impacting Factors Improve
Conclusion : 1.The normality plot shows that current data set is normal since P-value is greater than that 0.05 ( P-value>0.077)2.The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
Conclusion : 1.The normality plot shows that current data set is normal since P-value is greater than that 0.05 ( P-value>0.077)2.The scatter plot shows that there is a positive relation ship between reaction force & washer thickness.
04/14/2364
Screening of the Impacting Factors Improve
Trial conclusion- When we take the washer range size of 1.71to1.76mm , we get reaction force observed is above nominal value but within specification limit.However, by increasing the washer thickness, reaction force is also increasing.
04/14/2365
Screening of the Impacting Factors Improve
If we take washer thickness more than 1.76 mm ,we face following problems-
1.Insufficient Rivet height – If we increase the washer thickness above 1.76 mm, then we have to also increase the rivet height for proper hub sub assy.
2. Spring plate dimple dimension need to change- If we increase the washer more than 1.76 , then we have to also increase the spring plate dimple dimension for getting proper reaction force.
Trial-6 , If we take Washer thickness greater than>1.76 mm
04/14/2366
Screening of the Impacting Factors Improve
Trial-6 , If we take Washer thickness greater than >1.76 mm
Trial conclusion- Since for washer thickness more than 1.76mm,we have to change rivet height & spring plate dimple dimension so we could not take this opportunity for trial to check reaction force. Because it involve high cost .
04/14/2367
Screening of the Impacting Factors Improve
Trial conclusion- By different trials we get the following results-
Trial Washer Thickness Obtained Reaction force (N) Required Rxn Force (N)Spec. Trial-1 1.44~1.50 mm 88~95 90-130 Trial-2 1.51~1.55 mm 90~98 90-130 Trial-3 1.56~1.63 mm 95~105 90-130Trial-4 1.64~1.70 mm 104.30~112.50 90-130Trial -5 1.70~1.76 mm 110~120.50 90-130Trial-6 >1.76 mm Can not check
Result- By above observations we have decided to revised washer thickness from 1.44-1.76 mm to 1.56~1.76 mm.
04/14/2368
Child part used in Hub sub assy. Improve
Hub Spring plate Rivet-1
Rivet-2 Hub Washer
Armature Hub sub assy.
04/14/2369
Impact of changing washer thickness Improve
Before After
Comments- Washer having thickness 1.60±0.16 mm.
Comments- Modified washer thickness with specification 1.66±0.1 mm.
Benefit- - Clearance between spring plate, hub & armature will ensured . - Modified washer thickness helped in reduction of reaction force NG Problem.
04/14/2370
Impact of changing washer thickness specification to other part specification Improve
Hub
Comments- Hub dimension no need to change.
Comments- Armature dimension no need to change.
Armature
04/14/2371
Impact of changing washer thickness specification to other part specification Improve
Spring plate
Comments- Spring plate dimension no need to change
Revit-1
Comments- Rivet-1, dimension no need to change .
Revit-2
Comments- Rivet-2, dimension no need to change .
04/14/2372
Action Plan for Improving the Factors
# Pain Area Root Cause Improvement IdeaImplement
ation Owner
Implementation
Status
1
Washer thickness having lower side specification cause improper reaction force.
Less washer thickness cause more clearance between spring plate, hub & armature create improper reaction force.
Washer thickness required specification range revised & new washer thickness range defined with less variation ,Current specification was1.44~1.76 mm which has been revised to new specification 1.56 ~1.76 mm, to get proper reaction force,
•Mr. Amit Sharma/Dipak pandey
Done
Improve
04/14/2373
Basic Analysis of Improved YRandomness Study Randomness Study
Spread Study Spread Study
Improve
Improved Reaction force shows that process is stable since data are randomly distributed around mean.
P-Value for clustering, mixtures, trends , oscillation are greater than 0.05.
P-Value for-
Clustering> 0.286
Mixtures>.714
Trends>0.197
Oscillation>0.803
04/14/2374
Basic Analysis of Improved YGraphical summary Graphical summary
Improve
Graphical summary for improved Reaction force shows that process is normally distributed around mean since P-Value >0.05 .
P-value for improved process is 0.062.
04/14/2375
Basic Analysis of Improved Y Improve
Histogram for improved Reaction force shows that date points are normally distributed around mean ,
Process is centric & process variation is also less.
Anderson Darling test for improved reaction force shows that data points are falling on straight line & data is normal since P-value > 0.05
P-value for improved reaction force P=0.062
04/14/2376
Basic Analysis of Improved Y Improve
Improved process is capable since current process potential capability & actual capability are 3.01 & 2.30 respectively & which is acceptable as per AIAG guideline.
Current process potential performance & actual performance are 2.61 & 1.99 respectively Which is also acceptable as per AIAG guideline.
Current process is Stable & also in statistical control.
04/14/2377
Basic Analysis of Improved Y Improve
Current process is acceptable as long term process capability (ZLT) is 5.97 & short term process capability (ZST) is 7.47.
Current process is stable & also is in stastical control.
PPM has been reduced till 937.5 i.e within given target.
04/14/2378
Basic Analysis of Improved Y Improve
Before Improved project After Improved project
Six sigma project has been started to eliminate the same.
04/14/2379
Pre-Post Analysis of Project Y Reaction forceGraphical Description Before: Improvement Graphical Description Before: Improvement
Improve
Graphical Description After ImprovementGraphical Description After Improvement
The pre & post graphical distribution shows that pre-project the mean was 105.66 & post project this is 108.39, pre project the std. Dev was 13.05 & post project it is 6.06,also the P-value for pre project of improving reaction force was<0.05 & post project P-value is >0.05 i.e. 0.062,
04/14/2380
Pre-Post Analysis of Factor washer thicknessWasher Thickness Before improvementWasher Thickness Before improvement Washer Thickness After improvement Washer Thickness After improvement
Improve
The pre & post graphical distribution of washer thickness shows that before project the washer thickness variation is more & std. deviation is 0.0865 & the mean of the given data set is 1.589, while after improvement project the washer thickness variation is less & the std.dev is .0591 & the mean of the given date set is 1.668.
04/14/2381
Improve Summary – Take Aways Improve
Since low washer thickness cause improper reaction force so to get the correct washer thickness range, six trials for different washer thickness range done & used different statistical tool to see the relationship of getting reaction force with washer thickness. The result of all six trials are following- Trial Washer thickness Observed RXn force Specification limitTrial-1 1.44~1.50 mm 88~95 90-130 Trial-2 1.51~1.55 mm 90~98 90-130 Trial-3 1.56~1.63 mm 95~105 90-130Trial-4 1.64~1.70 mm 104.30~112.50 90-130Trial -5 1.70~1.76 mm 110~120.50 90-130Trial-6 >1.76 mm Not feasibleSince for washer thickness range 1.44~1.50 & 1.51~1.55 whatever the reaction force get that is either lower side or out side of desired specification.While by using washer thickness range 1.56~1.76 mm get better reaction force required for proper clutching.Trial for washer thickness range >1.76 mm can not do because for this washer thickness range ,rivet height & dimple dimension have to change so this is not feasible. So finally washer thickness range revised & decided a new washer thickness range of 1.56~1.76 mm, Made 100 pcs with modified washer thickness & checked reaction force ,Then draw the run chart found that data is stable, by graphical summary observed that data is normal & also calculate the capability of the process & is found that process is mature , stable & predictable.
04/14/2382
1. Control Plan & FMEA on Control Plan2. Time Series Study of Y – Pre & Post3. Control Charts & Inference for Y – Pre & Post4. Basic Analysis of Improved Y5. Establish Process Capability6. Control Charts & Inference (for X1)7. Control Charts & Inference (for X2)8. Cost Benefit Analysis and Sign Off
Control
04/14/2383
Control Plan & FMEA on Action Plan
What’s Controlled
Goal/Spec Limits
Control MethodWho/What Measures
Where Recorded
Decision Rule /
Corrective Action
SOP
1. Washer Thickness
1.66±0.1mm
5 Pcs check per lot in SQIG & Control chart
implemented to monitor the same.
SQIG Team/Washer thickness
Inspection check sheet
Washer thickness
must be within speciation.
Work instruction updated &
displayed at station for modified washer
thickness.
2. Reaction force
110±20 N
5 Pcs checked per shift & control chart implemented for monitoring the washer
thickness.
Line Engineer/Reaction
force
Product audit check sheet
Reaction force must be within specification.
Work instruction updated &
displayed at station
Control
04/14/2384
FMEA Review updating as per change washer thickness Improve
04/14/2385
Control Plan Review & updating Control
04/14/2386
Quality Plan Review Control
(1)Change in Washer thickness Dim. In Drawing & Inspection Test Plan.
04/14/2387
Control chart for Reaction Force Control
04/14/2388
Control Charts for Washer Thickness Control
04/14/2389
Basic Analysis of Improved Y Control
The pre & post graphical distribution shows that pre-project the mean was 105.66 & post project this is 108.39, pre project the std. Dev was 13.05 & post project it is 6.06,also the P-value for pre project for reaction force was<0.05 & post project P-value for same is >0.05 i.e 0.062.
04/14/2390
Z Bench (Long Term Sigma)
Short Term Sigma(Long Term Sigma +1.5)
5.97 7.47
Process Capability – Post Implementation
Establish Process Capability Control
Improved process is capable since current process capability is Cp=3.01 & Cpk =2.30 & current process performance is Pp=2.61 & Ppk =1.99
ZLT=5.97 & ZST=7.47
04/14/2391
ControlProject Summary
Define: It observed that hub assy Line rejection PPM reached up to 8526 PPM against target 1000 PPM due to improper clutching & clutch noise , caused by insufficient Reaction force between Hub & Rotor which leads to increase in customer complaints & hence customer dissatisfaction .Measure: Before Analysing the Problem we did- 1) validation of the measurement System by R & R Study and observed that the Measurement System is good enough for measuring the variation of the measurement System.2) Normality Test for the current Process data of Reaction Force which is found Non-Normal & very low Process Capability with one side skewness and draw run chart found that process is unstable.Analyze: During analysis we did brainstorming and validate all Potential Causes and found the Significant root Cause as improper reaction force is low washer thickness as reaction force is very much dependent on Washer thickness and check its effectiveness by performing co-relation & regression test.Improve: Since during analysis we found that assy line rejection PPM & customer complaint is due to improper clutching & clutch noise caused by insufficient Reaction force between Hub & Rotor and found that Improper clutching &clutch noise is due to less reaction force which we found is directly dependent on washer thickness.so we reduced the variation of the washer thickness to improve the reaction force.After implementation of new washer with revised thickness we checked the normality of Reaction force and found ok & Process capability of Washer thickness & Reaction force which is found more than 1.67 which confirms that the action taken has eliminated the root cause & hence reduce the assy line rejection PPM up to within target & customer complaint up to zero.Control: We Control the Action Plan taken by implementing the-1) Quality Plan for Washer thickness at Incoming Quality Stage.2) Control Chart for monitoring the Reaction Force & washer thickness and same has been updated in Control Plan & PFMEA.
04/14/2392
ControlProject Benefits
Compression Chart Pre & Post improvement
As per above comparison chart , we can see Line rejection PPM before improvement project was 8526 & customer complaint was 6 no's while after improvement project PPM is 937 ( which is within target) & customer complaint is 0.
04/14/2393
ControlCost Benefit Analysis
04/14/2394
Thanks Analysis
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