Action Plan made for Customer Indian Yamaha Motors on receiving Export complaint form Indonesia. Part name-Boss buffer which is fitted to weight balancer in the Engine. Complaint-OD-36.00(-0.03/-0.046mm) Oversize by 0.05mm. Problem-Fitment issue in the Engine assembly.

1. 1
Part : Boss Buffer 21C
Defect : OD 36 -0.030/-0.046 OD Over Size
Reported by : IYM, Surajpur (IPC)
Reported on : 19-March-2019

2. )
March-2019 - Critical Quality Problem
Model : 03F
Title : OD 36 -0.03/-0.046) O/S Boss buffer (21C-
E1496-20)
Countermeasure
<Found>
Responsibility : M/s. Varroc Engg.
Market
Production
Launching
T.P.
User
Approved by
S.ASAWA
Checked by
S. Patil
Prepared by
Harshal
Occurrence:
Out Flow:
1
# Training given to inspector about
OD Inspection through SOP
Imp. Date : 19-March-2019
# 100% inspection in 4-Jet Gauge.
# A separate metal cage box with lock
and key designed for inspectors to
reject the part accordingly as per the
job defect.
# Packing Area table shifted exactly to
the next of output.
# MT4 180mm center replaced
with MT4 140 mm length center.
# Stopper with locking
arrangement provided to restrict
wrong length MT4 center
installation.
# Identification mark provided on
MT4 center and linked with tool list
and setup approval report.
# Center MT4 with length 140 mm
defined in set up change SOP. To
avoid use of wrong length center
2
Out Line Of Problem CAUSEProcess Flow:
1st Find (Initial Analysis):
1 Occurrence:
Out Flow:2
NG Parts laying at VEPL analyzed for
physical phenomena
Visual :No dent, damages observed on OD.
Dimensional : High Ovality Observed on
NG Parts
Report Attached
Why1  OD oversize by 0.03mm
Why2  Non-Uniform grinding of the job.
Why3  Grinding wheel dressing not happened
properly.
Why4  Dressing insert worn out. Not giving proper
life.
Why1  Inspection Error
Why2  Judgemental error by operator.
Conclusion :- Judgemental error by operator
Problem Phenomenon:
OD over size by 0.03mm
Standard- ø36.0 (- 0.030/-0.046)mm
Actual - Max ø 35.970(+0.05mm) -
O/Size (19-Mar-19)
C&E Analysis
2

3. 3
Initial Analysis
Sr. No.
Outer Diameter Concentricity Parallelism
OD Ø36 (-0.030, -0.047) OD Taper OD Ovality
0.020 Max 0.040 Max
Min. Max 0.005 Max 0.005 Max
1 -0.063 -0.052 0.003 0.011 0.016 0.027
2 -0.047 -0.037 0.003 0.01 0.018 0.029
3 -0.072 -0.065 0.002 0.007 0.015 0.024
4 -0.068 -0.061 0.004 0.007 0.018 0.02
5 -0.072 -0.063 0.003 0.009 0.018 0.03
6 -0.03 -0.022 0.002 0.008 0.016 0.026
7 -0.039 -0.028 0.003 0.011 0.019 0.031
8 -0.031 -0.02 0.001 0.008 0.015 0.032
9 -0.032 -0.024 0.003 0.008 0.013 0.028
10 -0.031 -0.021 0.004 0.01 0.015 0.02
Conclusion NG OK NG OK OK

4. 4
Co-Relation with Centre length - Before
Dressing Frequency :- After 25 cycles (100 nos. Parts)
Srl No
Tail Stock Centre Length 180 mm
Ovality
(Spec :- 0.005)
Concentricity
(Spec:- 0.020)
OD 36-0.030/-0.046
A B C D A B C D A B C D
1 0.004 0.003 0.004 0.003 0.009 0.012 0.014 0.007 35.962 35.964 35.964 35.958
2 0.003 0.004 0.003 0.009 0.011 0.010 0.015 0.019 35.961 35.962 35.962 35.972
3 0.005 0.004 0.004 0.002 0.012 0.011 0.012 0.014 35.964 35.960 35.960 35.964
4 0.005 0.003 0.003 0.004 0.011 0.012 0.016 0.006 35.962 35.960 35.961 35.962
5 0.004 0.004 0.003 0.002 0.013 0.013 0.014 0.009 35.959 35.964 35.962 35.962
6 0.004 0.003 0.003 0.008 0.012 0.012 0.016 0.019 35.959 35.962 35.962 35.973
7 0.003 0.004 0.004 0.003 0.015 0.011 0.014 0.012 35.960 35.960 35.962 35.961
8 0.003 0.004 0.003 0.008 0.009 0.012 0.016 0.015 35.962 35.965 35.961 35.952
9 0.004 0.003 0.004 0.005 0.012 0.013 0.013 0.007 35.961 35.964 35.964 35.962
10 0.004 0.004 0.003 0.004 0.013 0.012 0.014 0.009 35.962 35.962 35.963 35.962
11 0.003 0.004 0.004 0.006 0.012 0.011 0.015 0.015 35.964 35.959 35.962 35.972
12 0.003 0.003 0.004 0.003 0.011 0.012 0.016 0.007 35.968 35.959 35.961 35.961
13 0.003 0.004 0.003 0.004 0.012 0.012 0.017 0.012 35.962 35.960 35.964 35.964
14 0.004 0.004 0.004 0.003 0.014 0.014 0.018 0.009 35.961 35.962 35.961 35.963
15 0.004 0.003 0.003 0.005 0.016 0.015 0.014 0.015 35.962 35.961 35.962 35.962
16 0.004 0.004 0.004 0.005 0.012 0.013 0.013 0.010 35.962 35.962 35.958 35.960
17 0.003 0.003 0.003 0.007 0.012 0.015 0.012 0.016 35.960 35.964 35.962 35.953
18 0.003 0.004 0.003 0.007 0.010 0.012 0.014 0.015 35.960 35.965 35.964 35.952
19 0.004 0.005 0.003 0.004 0.009 0.013 0.016 0.006 35.961 35.961 35.962 35.962
20 0.003 0.004 0.003 0.006 0.010 0.015 0.014 0.014 35.962 35.959 35.967 35.972
21 0.003 0.003 0.003 0.004 0.012 0.012 0.013 0.018 35.964 35.959 35.965 35.965
22 0.004 0.004 0.004 0.003 0.013 0.012 0.014 0.019 35.965 35.958 35.966 35.964
23 0.003 0.004 0.004 0.004 0.013 0.013 0.015 0.016 35.962 35.959 35.962 35.962
24 0.003 0.003 0.003 0.004 0.014 0.014 0.016 0.009 35.965 35.960 35.964 35.965
25 0.004 0.002 0.004 0.003 0.016 0.013 0.016 0.002 35.961 35.961 35.962 35.961
26 0.005 0.003 0.003 0.008 0.014 0.012 0.014 0.018 35.959 35.962 35.963 35.952
27 0.004 0.003 0.004 0.007 0.012 0.016 0.013 0.015 35.959 35.962 35.964 35.971
28 0.003 0.004 0.003 0.003 0.010 0.012 0.014 0.004 35.958 35.960 35.965 35.958
29 0.004 0.003 0.004 0.004 0.012 0.013 0.012 0.008 35.959 35.960 35.962 35.959
30 0.004 0.004 0.003 0.008 0.013 0.012 0.013 0.018 35.960 35.961 35.963 35.953
A B C D
PART LOCATION ON HYDRAULIC MANDREL

5. 5
BEFORE AFTER
Part rotation point not added in Multigauge inspection SOP
OD size and Ovality inspection by using 4 jet Multigauge
SOP for ID and OD Inspection on Multigauge

6. OD Grinding machine centres
Before After
MT4 center with 140 mm lengthMT4 center with 180 mm length
Boss Buffer OD Under Size and Over Size
180 mm length
140 mm length
40 mm Over Hang
`20 mm

7. OD Grinding Machine Layout
 Stopper with locking arrangement to be provided to restrict wrong length MT4 center installation on machine.
Target Date :- 30-Apr-2017
Head stock
Tail stock
Yellow Marking for Head Stock Position Stopper with Locking Arrangement
Yellow Marking for Tail Stock Position
Stopper

8. 8
Mistake Proofing at Storage
 Shadow Board To be Provided to avoid wrong center storage and issue to production

9. Identification of Tailstock Center

10. 10
MT4 Over Hang Length and Identification mark verification during setup Change
10

11. OD Grinding Process Setup Approval
Setup Approval Frequency revised – 5 cycles rather than 01 or 02 cycles

12. Setup Change SOP :- Centre length specification added in SOP
Boss Buffer OD Under Size and Over Size

13. 13
Effectiveness monitoring Trend

14. 14
Co-Relation with Centre length - After
Dressing Frequency :- After 25 cycles (100 nos. Parts)
Tail Stock Centre Length 140 mm
Ovality
(Spec :- 0.005)
Concentricity
(Spec:- 0.020)
OD 36-0.030/-0.046
A B C D A B C D A B C D
0.003 0.003 0.001 0.002 0.012 0.011 0.014 0.014 35.965 35.965 35.960 35.965
0.002 0.003 0.003 0.003 0.007 0.012 0.012 0.013 35.96 35.961 35.961 35.961
0.003 0.001 0.004 0.004 0.010 0.013 0.011 0.014 35.955 35.961 35.962 35.961
0.003 0.001 0.003 0.002 0.012 0.014 0.013 0.015 35.962 35.962 35.961 35.965
0.002 0.003 0.002 0.003 0.015 0.016 0.014 0.016 35.961 35.958 35.959 35.961
0.003 0.004 0.003 0.001 0.016 0.014 0.015 0.009 35.962 35.961 35.959 35.962
0.004 0.004 0.004 0.002 0.009 0.013 0.015 0.015 35.960 35.962 35.962 35.964
0.002 0.004 0.002 0.003 0.009 0.014 0.012 0.007 35.961 35.964 35.960 35.962
0.003 0.002 0.002 0.003 0.009 0.012 0.011 0.012 35.962 35.965 35.960 35.961
0.002 0.003 0.002 0.003 0.002 0.009 0.012 0.013 35.962 35.961 35.962 35.965
0.002 0.003 0.003 0.001 0.009 0.007 0.011 0.015 35.964 35.962 35.961 35.964
0.003 0.002 0.003 0.002 0.004 0.009 0.013 0.012 35.968 35.958 35.962 35.962
0.002 0.003 0.002 0.003 0.011 0.015 0.014 0.012 35.962 35.962 35.964 35.959
0.003 0.004 0.003 0.003 0.006 0.007 0.015 0.005 35.962 35.962 35.968 35.959
0.003 0.002 0.004 0.002 0.006 0.012 0.016 0.003 35.964 35.961 35.962 35.962
0.003 0.003 0.002 0.003 0.005 0.012 0.017 0.002 35.962 35.961 35.961 35.960
0.004 0.001 0.003 0.004 0.003 0.013 0.018 0.012 35.967 35.959 35.965 35.960
0.002 0.003 0.001 0.002 0.002 0.015 0.014 0.015 35.964 35.959 35.961 35.961
0.003 0.003 0.002 0.003 0.004 0.012 0.013 0.009 35.962 35.961 35.964 35.962
0.004 0.004 0.003 0.001 0.008 0.012 0.016 0.012 35.962 35.964 35.962 35.964
0.004 0.003 0.003 0.001 0.012 0.013 0.016 0.009 35.964 35.961 35.967 35.968
0.004 0.002 0.003 0.003 0.015 0.014 0.017 0.007 35.965 35.964 35.965 35.962
0.003 0.003 0.001 0.004 0.009 0.017 0.012 0.009 35.967 35.962 35.966 35.967
0.002 0.001 0.001 0.004 0.005 0.018 0.011 0.015 35.965 35.962 35.962 35.965
0.003 0.002 0.003 0.004 0.002 0.014 0.012 0.007 35.966 35.964 35.967 35.966
0.001 0.002 0.002 0.003 0.002 0.007 0.011 0.012 35.962 35.962 35.962 35.965
0.002 0.002 0.003 0.002 0.005 0.012 0.013 0.017 35.964 35.967 35.961 35.964
0.002 0.003 0.003 0.003 0.007 0.011 0.014 0.011 35.965 35.962 35.962 35.962
0.002 0.004 0.002 0.001 0.007 0.014 0.017 0.012 35.961 35.958 35.964 35.959
0.003 0.002 0.003 0.002 0.006 0.012 0.018 0.015 35.961 35.962 35.968 35.959

15. 15
Air Gauge Setting SOP
4 Jet OD Inspection Gauge SOP Training for Job Rotation

16. DEFECT PART IDENTIFICATION
Part defect wise identification started in Q-Gate where inspector can easily shuffle parts
into the box as per the defect.

17. 17
PACKING AREA SHIFT
Previously Packing table kept side
opposite to the inspection table.
Packing Table shifted adjacently to the
inspection table area.

18. 18
OD 35 over
size
MachineMethod
ManMaterialTools
Wheel Balancing not done
Part clamping not
proper in grinding
wheel
Setup error
Mandrel Face run out more
C&E Analysis For OD Under Size(OD Grinding)
Wrong offset given
No Awareness
Measurement
Less Operator Inspection
Skill
Center worn out
Dresser worn out
Excess Load On The Wheel
While Operation

19. Potential Causes Validation
Back
S. No. Category Potential Cause Standard How to Check Observation Results
1
Method
Wheel Balancing
not done
No forward and
backward movement
Wheel balancing unit
Setup approval after
tool change
OK
2
Part clamping in
loose condition
No loose clamping By hand
No loose clamping
observed
OK
3 Setup error No setup error
Setup approval
report
Setup Ok as per
control plan
OK
4
Measurement
Wrong Gauge Used
Snap Gauge (As per
CP)
In-Process Audit
Gauge used as per
control plan
OK
5
Calibration not
done
Should be calibrated Calibration report
Calibration record is
OK
OK
6
Less Operator
Inspection Skill
Skilled operator
Skill matrix and
operator interview
Operator not
checking part by
rotating in gauge
NG
10 Man Wrong offset given No wrong offset
Setup approval
report
Setup Ok as per
control plan
OKOffset given by
skilled supervisor
only
11
Tool
Mandrel Face run
out more
< 0.005 mm
Between center and
Dial
0.004 (PM Sheet) OK
12
Both Center worn
out
No center worn out Visual
No center worn out
observed (PM sheet)
OK
13
Mandrel locating OD
worn out
15-0.015 mm micrometer 14.992 (PM Sheet) OK
14
Mandrel OD run
out more
< 0.005 mm
Between center and
dial
0.004 (PM sheet) OK
15 Dresser worn out No dresser worn out Visual No dresser worn out OK

20. 20
Inward Inspection Report

21. 21
Inward Inspection Report

22. 22
Mandrel PM sheet

23. 23
Calibration Certificate – Snap Gauge (Machine)

24. 24
Calibration Certificate – Snap Gauge (Final Inspection Stage)

25. 25
100% Id Inspection on machine

26. 26
Skill Matrix

27. 27
Boss Buffer 4 Jet OD and Ovality Inspection gauge

28. 28
Cp : 2.19 and CpK : 1.73
OD Grinding Machine Process Capability by using 4 Jet Air Gauge

29. 29
Boss Buffer Final Inspection Plan

30. 30
Training Provided To Final Inspector

31. 31
Boss Buffer OD Grinding PFMEA