Slide 1 Copyright, Confidential, Tata Motors Ltd
Team: Brake System
7 Step QC story
7 Step QC storyProblem Solving Methodology
SUMO Front Brake pad worn out
Slide 2 Copyright, Confidential, Tata Motors Ltd
Review with Mentor - Mr G R Nagbushan
Review with Champion - Mr Suyog panse
Review with Team Leader - Mr Bisen Badal
Team Charter
Team Leader - Mr.Bisen Badal
Co - Leader - Mr. Ramani K.R
Team Members -
Mr. Jagdish G Naganoor, Mr.K.Pavan, Mr.Karadi S.B, Mr.Gharat .R.V,
Mr.Kulkarni S.G, Mr Mhaske, Mr Deshpande.R, Mr Patil suhas,Mr
Diwakar.R, Mr Satyajit Patil.
Review Mechanism
Target
(6Monthly IPTV- May12
Production Batch)
SUMO GOLD
ModelCurrent Status
(6Monthly IPTV- Aug 12
Production Batch)
0.66+1.99
Training Needs
Goal Structure
# Warranty reduction of Brake judder/ Pad worn out- issue
resolution by structured problem solving methodology
# Developing Detection Strategy throughout manufacturing
and inspection process
# Updating Design Guideline, DFMEA, DVP, RFQ and
Process Documents based on Failure Mode Analysis and
Permanent Corrective Actions
Target
0
0
0
0
7 Step QC storyProblem Solving Methodology
Step: 1 Define Project: Team Charter & Goal Statement
Slide 3 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 1 Define Project: Team Charter & Goal Statement
CFT STRUCTURE- Define Roles & Responsibility
Aggregates : Brakes Project Front brake pad worn out/ Defective
Mentor : Champion: Bisen Badal
SR No Team member Contact no Role Department
1 Mr. Gharat.R.V 8149059178 QA
2 Mr. Kulkarni.S.G QA
3 Mr. Mhaske QA
4 Mr. Karadi.S.B 7276045242 ADD
5 Mr. Deshpande.R APL
6 Mr. Jagdish G.N ERC
7 Mr. Pavan.K 8149095987 ERC
8 Mr. Asnikar.G 9881509735 ERC
9 Mr. Suhas Patil Mfg
10 Mr. Diwakar.R Mfg
11 Mr. Satyajit Patil Six Sigma
Slide 4 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 1 Define Project: Action Planner
Action planner 2013
Feb March April May
Project : Brake Pad worn out 4 5 6 7 11 12 13 14 15 18 19 20 21 25 26 27 28 29
PLA
N
Team Charter CFT formation Plan
Act
GOAL Statement Target Definition Plan
Act
Data Collection Warranty / JD/ CC DVP/ DFMEA/ Standards / PFMEA/ SOP/WI
Plan
Act
Data Stratification Multi level paritoPlan
Act
Failed part s analysis
On test rig/ Vehicle analysis (Min 30 failed parts
Plan
Act
Problem Definition Focused issue to be worked upon
Plan
Act
Deeper Analysis Why- Why / 5W-2H analysis Plan
Act
Bench marking Competitor products/ Process benchmark (min 3)
Plan
Act
Cause Effect Analysis
Ishakawa Diagram Plan
Act
Plan Action Progress
Slide 5 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 1 Define Project: Action Planner
Action planner 2013
FEB MARCH APRIL MAY
Project : Brake Pad worn out 4 5 6 7 11 12 13 14 15 18 19 20 21 25 26 27 28 29
DO
ContainmentAction
Interim Corrective Action
Plan
Act
Verification & Validation of causes
3G Analysis
Plan
Act
Root cause analysis 7QC tool and 8D methodology
Plan
Act
Verification & Validation
Sample batch tryout Plan
Act
ActionImplementation
Permanent corrective action
Plan
Act
Ch
eck
Check Results Warranty / JDP/ Customer complaints
Plan
Act
Act
ion
Recurrence prevention
Capture the learning & documents DFMEA, PFMEA , Design rule, Control plant/ WI
Plan
Act
Standardization Horizontal deployment Plan
Act
Felicitation Plan
Act
Plan Action Progress
Slide 6 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 1 Define Project: Bird Eye view
Fie
ld IP
TV
In P
rocess
FY10-11 FY12-13FY11-12
In-H
ou
se R
eS
up
pli
er
EO
L
FSO Not Ok at TML for assly run out (nos)
0 0 0 0 03
0
13
0 0 0 0 0
0
25
50
75
Jan-
11
Feb-
11
Mar
-11
Apr-1
1
May
-11
Jun-
11
Jul-1
1
Aug-
11
Sep-
11
Oct-1
1
Nov-11
Dec-11
Jan-
12
nos
Brake disc Primary Rejection VQA( nos)
0 0 0 0 0 0 0 0 0 0 0
29
0
25
50
75
Jan-
11
Feb-
11
Mar
-11
Apr-1
1
May
-11
Jun-
11
Jul-1
1
Aug-
11
Sep-
11
Oct
-11
Nov-
11
Dec-
11
nos
No data available
Take away: Detection adequate at Process, incoming stage for brake disc and hub defects.No failure of wheel cylinder at assly stage.
Bird Eye View
Brake disc Primary Rejection VQA( nos)
04
10
0 05
0 0 0 0 0 0 0
0
25
50
75
Jan-
12
Feb-
12
Mar
-12
Apr
-12
May
-12
Jun-
12
Jul-1
2
Aug
-12
Sep
-12
Oct
-12
Nov
-12
Dec
-12
Jan-
13
nos
Data not available
Supplier Data Not Available for
brake pad, caliper defects
FSO Not Ok at TML for assly run out (nos)
0 0 0 0 03
0
10
30 1
40
0
25
50
75
Jan-
12
Feb-
12
Mar
-12
Apr
-12
May
-12
Jun-
12
Jul-1
2
Aug
-12
Sep-
12
Oct
-12
Nov
-12
Dec
-12
Jan-
13
nos
Data not available Data not available
Slide 7 Copyright, Confidential, Tata Motors Ltd
5.98
1.99
1.33
0.66 0.66 0.66
53%
71%
82%88%
94%100%
0
1
2
3
4
5
6
7
REAR
WHEEL
CYLINDER
BRAKE
DISC
VACUUM
BOOSTER
BRAKE
FIEXIBLE
HOSE
BRK
LINERS
CALIPER
PAD
Compl Description
IPT
V
0%
20%
40%
60%
80%
100%
120%
40
20
14
14
12
11
9 7
5 5
2 1 1
29%
43%
53%
63% 71% 80% 86%
91%
94%
97%
99%
99%
100%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0
5
10
15
20
25
30
35
40
45
Ele
ctr
ica
ls
Ca
b
Clu
tch
En
gin
e
En
gin
e e
lec
tric
als
Bra
ke
s
HV
AC
Ste
eri
ng
Su
sp
en
sio
n
Ax
le
Co
oli
ng
Ch
as
sis
Ge
ar
bo
x
Pe
rce
nta
ge
Cm
pls
(IP
TV
)
Aggregates
7 Step QC storyProblem Solving Methodology
Step: 2 : Observation:2.0- Data Collection
Sumo
Model level IPTV 141
Brakes 6M IPTV 11
% Contribution 8%
98
6
23
8
19
3 1 4
5
1 2
4 6 3 4 1 3 2 1 0 2 2
106
15
34
20 2
4
12
6 7 8 9
10
4
11
9
18
33
18
25
15
26
19 22
20
17
26
16
11
11
122
33
59
29
43
41
10
28
25
23 2
8
18
53
64
56 6
2
60 6
6
41
77
69
65
124
38
70
35
54 5
9
16
39
30 31 32
23
66
75
71
70
124
40
73
37
5761
21
41
3331
0
20
40
60
80
100
120
140
May/1
0
Ju
n/1
0
Jul/10
Aug/1
0
Sep/1
0
Oct/
10
Nov/1
0
Dec/1
0
Ja
n/1
1
Feb/1
1
Mar/
11
Apr/
11
May/1
1
Ju
n/1
1
Jul/11
Aug
/11
Sep/1
1
Oct/
11
Nov/1
1
Dec/1
1
Ja
n/1
2
Feb/1
2
Ma
r/1
2
Apr/
12
May/1
2
Ju
n/1
2
Jul/12
Aug/1
2
Sep/1
2
Oct/
12
Cm
pls
/ 1
000
3 mth 6 mth 12 mth 18 mth 24 mth
Brake Aggregate Graph
Slide 8 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
JAN FEB MAR APR MAY JUNE JULY AUG
No of vehicle produced 3058 2890 2982 3221 3564 2393 1506 2979
No of complaints 58 65 61 55 93 39 17 33
0
50
100
150
200
0
500
1000
1500
2000
2500
3000
3500
4000
No
of
Co
nce
rns
No
of
veh
icle
pro
du
ced
Model Wise Production Vs Reported Complaints (Brake Aggregates) Period - JAN 12 To AUG 12
19
22
17
20
26
16
11
11
Step: 2 : Observation:2.1- Data Collection
Brake complaints shows down trend after June batch production by approx 40%
Production Batch
6-Monthly IPTV
Brake pedal hole tolerance revised on NOV -11
Stop light switch gap adjustment gauge introduced at TCF
Corrective Action Implemented
Gap checking gauge introduced at final inspection
Slide 9 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Wheel cylinder leak/Sc
ored
Brake disc
runout/ uneven contact
Brake vacuum booster
all defects
Caliper pad
worn/ Crack
Caliper assy all defects
Brake liners worn/
cracked
Parking brake cable defect
Brake master
cyl leak/ Scored
Brake drum
scored/ uneven contact
Brake pipe
crack/ Leak
Brake line
connectors leak
Brake Hose
crack/ Leak
ABS all defects
LCRV Defectiv
e
Hand brake lever knob
broken
Brake fluid
container/ leak
No of complaints 314 276 112 71 50 44 43 24 23 17 8 7 6 3 2 2
cum % Age 31 59 70 77 82 86 90 92 94 95 96 97 98 99 100
31
59
70
7782
8690 92
94 95 9697 98 99
100
0
20
40
60
80
100
120
0
50
100
150
200
250
300
350
Cu
m %
Age
No
of
veh
icle
pro
du
ced
SUMO BRAKE COMPLAINTS RECEIVED DEFECT WISEPeriod - JAN 12 To AUG 12 production batch
Step: 2 : Observation:2.1- Data Collection
Top Four Brake complaints contributes 77% of total brake aggregates complaints .
Slide 10 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
JAN FEB MAR APR MAY JUNE JULY AUG
VEHICLE PR 3058 2890 2982 3221 3564 2393 1506 2979
No of complaints 11 12 10 10 19 3 1 5
0
500
1000
1500
2000
2500
3000
3500
4000
0
5
10
15
20
No
of
Ve
hic
le p
rod
uce
d
No
of
Co
mp
lain
ts
Front Brake pad Worn out Monthly IPTVPeriod - JAN 12 To AUG 12
3.54.1 3.3
3.15.3
1.2
0.6
3.5
NORTH SOUTH WEST EAST
No of complaints 37 16 11 6
% Age 53 72 95 100
53
72
95100
0
20
40
60
80
100
0
10
20
30
40
%A
ge
No
of
Co
mp
lain
ts
Front Brake pad Worn out Region WisePeriod - JAN 12 To AUG 12
Delhi Bangalo
rePune
Deharadun
Bijapur Mumbai Others
No of complaints 29 13 9 3 2 2 10
% Age 43 62 75 79 82 85 100
43
62
75 7982 85
100
0
20
40
60
80
100
0
5
10
15
20
25
30
35
%A
ge
No
of
Co
mp
lain
ts
Front Brake pad Worn out City WisePeriod - JAN 12 To AUG 12
> 5K 5K-10K 10k-15K 15K - 20K
No of complaints 12 9 33 18
0
5
10
15
20
25
30
35
No
of
Co
mp
lain
ts
Front Brake pad Worn out Kms WisePeriod - JAN 12 To AUG 12
Step: 2 : Observation:2.1- Data Collection: Front brake pad worn out
Pad worn out trend is similar to overall brake aggregates trend .
75 % of Pad worn out cases are reported from dense city traffic condition.
Slide 11 Copyright, Confidential, Tata Motors Ltd
Step: 2 : Observation:2.1- Data Collection :: Front brake pad worn out
7 Step QC storyProblem Solving Methodology
Matrix Chart
Brake pad Defective
Brake pad hard/ Glazed
Brake Pad worn out
UnevenWear Total % Age
Brake Grabbing 1 3 4 5%
Brake Hard 1 1 2 3%
Brake Insufficient 4 3 10 2 19 27%
Brake Jam 3 1 4 6%
Brake Noisy 3 25 2 31 44%
Brake shuddering 11 11 15%
Grand total 5 7 53 5 71 100%
% Age 7% 10% 76% 7% 100%
Dealer
Analysis
Customer
Verbatim
86 % Customer has reported Brake noisy , Brake insufficient & Brake Shuddering due to front brake
pad worn out.
76 % of complaints found that the friction material was completely worn out .
PCR data received from Jan 12- Aug-12
Slide 12 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Matrix Chart
Brake pad Hard/ Glazed
Brake Pad worn out
Total % Age
Brake Pad Defective 15 15 48%
Brake Pad Hard/ Glazed 2 2 4 13%
Brake Pad Worn out 9 9 29%
Uneven Wear 3 3 10%
Grand total 2 29 31 100%
% Age 6% 94% 100%
Failure
Mode
Dealer
Analysis
Step: 2 : Observation:2.1- Data Collection :: Front brake pad worn out
94 % of complaints reported found that the friction material was completely worn out .
Material Receipt at TML & Investigated
Slide 13 Copyright, Confidential, Tata Motors Ltd
Step: 2 : Observation:2.2- Under Standing
7 Step QC storyProblem Solving Methodology
Process documents, drawings, Control Plans, WIS, DVP, DFMEA, Design Guideline
Dealer
AnalysisDESIGN CONTROLS
Sl No Design Control Activity Document
1 Front Caliper/ Brake pad Part Drawing Release
2 Information Fitment Drawings
3 Design Validation Plan (DVP)
4 DFMEA
5 Test Specifications (TS)
6 Service Advisory
7
8
Slide 14 Copyright, Confidential, Tata Motors Ltd
Step: 2 : Observation:2.3- Failed part Analysis
7 Step QC storyProblem Solving Methodology
Visual / On Test Rig / Vehicle analysis (Minimum 30 failed parts)
Dealer
Analysis
Test on
Vehicle
Friction material property analysis
Pass
Critical parameters Measurements
Root cause Identification
Visual Inspection
Feedback to dealer through CS
Trials with
customer
support
Fail
Pass
Testing
on Test
rig
Fail
GAP ANALYSIS
Simulating testing
methods with Actual
customer usage.
DVP up-dation.
Identifying new test
methodology
OK
NOT OK
OK
Slide 15 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Brake pad defectiveBrake pad hard/ GlazedBrake pads worn out Uneven wear
Dealer Analysis 15 4 9 3
0
2
4
6
8
10
12
14
16
Nu
mb
er
of
com
pla
ints
Level-1 Pareto for Pad worn out -Front
Pads wornout
Concern observations 15
0
2
4
6
8
10
12
14
16
Nu
mb
er
of
com
pla
ints
Level-2 Pareto for Brake Pad Defective
Brake pad hard/ Glazed
Brake pad worn out
Concern observations 2 2
0
1
2
3
4
5
6
Nu
mb
er o
f co
mp
lain
ts
Level-2 Pareto for Brake Pad Hard / Glazed
Pads worn out
Concern observations 12
0
2
4
6
8
10
12
14
Nu
mb
er o
f co
mp
lain
ts
Level-2 Pareto for Brake pads Worn out & Uneven wear
Step: 2 : Observation:2.3- Failed part Analysis
29 number of incidents analyzed and found that friction material was completely worn out .
Total number of complaint investigated - 31
Slide 16 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 2 : Observation:2.5- Problem Definition
Brake pad Worn out
Brake
Grabbing
Brake Pad Defective
Brake pad
worn out
Brake
Hard
Brake pad
Hard/Glazed
Brake pad
Worn out
Brake insufficient
Brake pad
Defective
Brake pad
Hard/Glazed
Brake pad
Worn out
Uneven
wear
Brake Jam
Brake pad
Worn out
Uneven
wear
Brake
Noisy
Brake pad
Hard/ Glazed
Brake pad
Worn out
Uneven
Wear
Brake Shuddering
Brake pad
Worn out
Brake pad
Worn out
Brake pad
Hard/Glazed
94% 6%
4 2 19 4 31 11
94% of complaint found that friction material on front brake pad was completely worn out .
Slide 17 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Pedal box Assembly
Stop light switch
Brake pedal
Booster Assembly
Knuckle assembly
Disc
Caliper
Step: 2 : Observation:3- Understanding design, mechanism and functionality, benchmarking comparison at concept level
Stop light switch gap
adjustment
Slide 18 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Front brake
pad worn out
Aggregates Un cleaned
SUPPLIER
Brake pad inconsistence
properties
Lack of 100% Roll back inspection
Pads fitted in reverse direction
TML
Brake fluid contamination
Brake light switch improper adjustment
High lateral hub play
Skip or improper knuckle
assembly critical
parameter, DTV/ Run-out
Clevis pin tight
Step: 3 : ANALYSIS : 3.0- CAUSE EFFECT ANALYSIS Ishikawa Diagram for each defect
Low roll back
Knuckle
Caliper
DISC/DRUM
Brake pedal Assembly
Pedal pivot point tight
Brake light switch
improper adjustment
Clevis hole/pin tight
Brake Booster Assembly
TMC cutoff port blocked
Firewall deflection
TMC seal swell
Excess out put rod setting
High standout setting
Sluggish return
Caliper mount improper parallelism
Caliper mount offset
Sliding pin bend/ Jam
Poor Surface finish
High DTV / Run out
Environment Condition
Rainy
Excessive dust / Sand.
Coastal Area
brake servicing at Un authorized
service centers
Service
Usage of non genuine spare parts
Vehicle Overloading
Customer Usage
Rim/Tire modifications
High traffic/ Hilly terrain
TAXI/ Personnel
Knuckle
Brake system
Improper pad selection
Improper brake distribution
Caliper mount offset specification
HUB
Higher Run-out value
Higher surface finish value
Brake fluid
Improper grade selection
Brake Pads
High wear rate
Higher caliper roll back
Slide 19 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 3 : Analysis : Cause & Effect Matrix
Slide 20 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 2 : Observation:2.4- Problem Definition
Analysis results- Summary
CALIPER PAD WORN OUT/FRONT (KC 42011)
1 Improper Stop light switch adjustment.
2 High residual drag on BIL caliper 75Kgcm, due to mue-set shims.
3 Brake pedal sluggish due to tight tolerances of clevis pin & pedal hole.
4 Appache 522/12 friction material inconsistence in performance. Poor performance & wear characteristics in City & Hilly region application
Slide 21 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
Step: 2 : Observation:2.4- Problem Definition
Action plan - Summary
CALIPER PAD WORN OUT/FRONT (KC 42011)
1
Brake stop light switch adjustment with designed gap gauge implemented on production line from March-2012.
As a Poke-Yoke new snap-on type brake stop light switch is designed. Implementation planned from March -2013.
2
Mass added caliper (C57), is under validation with Wolverine shim with target residual drag of 50 kg cm, against current 75 kg cm.
Implementation planned from May - 2013.
3 Brake pedal hold designed tolerances revised & implemented in production since June -2012.
4R 808 friction pads are under validation for performance & wear.
Implementation planned from May 2013, along with mass added caliper.
Slide 22 Copyright, Confidential, Tata Motors Ltd
7 Step QC storyProblem Solving Methodology
THANK YOU