six sigma project final

Q-Star Advance Project 1© Copyright, Confidential, Tata Motors Ltd

Lean Six Sigma ProjectLean Six Sigma Projectonon

To eliminate sub frame mtg. hole To eliminate sub frame mtg. hole mismatch with frame nut in TCFmismatch with frame nut in TCF

Submitted by Pradeep Tiwari Ticket No. 602551

Deptt. Biw – 1C Program /Module SIX SIGMA


Project Selection Check ListProject Selection Check List

No. Criteria Yes No

1 Project is a strategic priority, aligned with a Big Y √

2 There is no overlap with other GB / BB projects √

3 Scope of the project is under the area of my influence √

4 Project scope is limited to only one product / one type of defect √

5 It is related to repetitive problem (chronic, not sporadic) √

6 Team cannot solve it by engineering judgment. √

7 A significant ROI expectation has been established √

8 Right vertical & horizontal team members are available √

9 Several team members are top talent & innovative thinkers √

10 Management is willing to commit serious resources to solutions √

11 Project is capable of completion within 2~4 months √

12 Capable team leader and champion assigned √


Business Case / Justification for Project Selection Opportunity Statement

The project supports DRR & DRL improvement, COPQ Reduction and line stoppage reduction of TCF Shop.

Pain : Product is getting reworked at TCF and extra 2 manpower deployed it’s repairing. Majorly produced vehicle are having same defect.

Quantification : DPV of product is 3.5 & Daily 2 manpower are required for reworking this particular defect.

Impact of pain in Rs. (or soft) : Rs.20.9 lack p.a. is paid for this rework.

Goal statement Project scope Metric Current level Target The scope of the project begins at the time of cab being

received at TCF from Paint Shop until the vehicle is fully assembled and made ready for dispatch.

Sub frame rework in Super Ace / Venture

70-75% rework Zero Rework

DPV- 3.5 DPV-1.0

Project plan TeamPhase Start End Role Name Dept.

Sponsor Mr. S. Waghchaure BIW – 1C

Define 01/09/14 12/10/14 Champion / Guide Mr. Mohanish Q OMeasure 13/10/14 24/10/14 Leader Pradeep Tiwari BIW – 1C

Analyze 02/11/14 29/11/14 Member Ganga Singh BIW – 1C

Improve 30/11/14 31/12/14 Member Vikrant TCF – 1C

Control 01/01/15 30/01/15 Member Pankaj Adhikari BIW – 1C

Member Ritesh Chattoo SQIG

Project CharterProject Charter


•The issue of Sub frame rework in DRR TCF 1C was taken up as Six Sigma project and the reason is evident from the above table. Since there are multiple and complex causes with no proper solution, I have, with the support of the management, decided to use DMAIC approach to solve the problem.

Why Sub frame fitment problem as a Six sigma project?


DEFINE

What is the pain?


DEFINE PHASEProblem Identification & JustificationProblem Identification & Justification

(KPM Tree – Business Goal)(KPM Tree – Business Goal)

PLANT QUALITY PERFORMANCE IMPROVEMENTPLANT QUALITY PERFORMANCE IMPROVEMENT

CPA CPA IMPROVEMENTIMPROVEMENT

REDUCE CUSTOMER REDUCE CUSTOMER (TCF) COMPLAINS(TCF) COMPLAINS

Big Y(Metric)

Small y’s(Key drivers)

Vital X’sDIRECT RUN LOSS DIRECT RUN LOSS

IMPROVEMENTIMPROVEMENTDIRECT RUN RATE DIRECT RUN RATE

IMPROVEMENTIMPROVEMENT

SHOP QUALITY PERFORMANCE IMPROVEMENTSHOP QUALITY PERFORMANCE IMPROVEMENT

Engine Engine cover to cover to

console gap console gap N.G.N.G.

Door Door glass glass HardHard

L/B tail L/B tail gate panel gate panel

foulfoul

Sub frame Sub frame mtg. hole mtg. hole mismatchmismatch

Tail gate Tail gate to side to side panel panel

gap N.G.gap N.G.


Problem Identification & Justification(Pareto & Trend Chart)Problem Identification & Justification(Pareto & Trend Chart)DEFINE PHASE


Assy. Sub frame with frame

Two Center Stud (LH/ RH) used to mount the engine carrying sub frame

Mounting of remaining 8 studs and 6 bolts was done after the engine stuffing process.


DEFINITION OF PROBLEM

Frame & Sub frame hole mismatch with jack mount

stud position.

Side Bkt Nut offset with Sub frame Mismatch with front stud

Sub frame hole mismatch with Frame Inner BKT

FRAME

SUB FRAME


TCF Process

Engine assy. With Sub Frame.

Sub frame fastener torquing.

Comp. Assy sub fame from BIW

Assy. Comp. frame from BIW end

Assy. Engine in TCF with Sub Frame

Matching of sub frame & frame in TCF


Assy comp. frame S.Ace

Side Mtg Bkt

Front Stud Mtg Bkt

Jack Mtg Bkt

Centre Stud Mtg Bkt

Total No. of Sub frame mtg Nuts 16 No.


Finished Assy. Sub frame Rack & Pinion

Mtg BktSide Mtg Bolt

Front Stud Mtg Hole

Jack Mtg Hole

Rack & Pinion Mtg Bkt

Side Mtg Bolt

Centre Stud Mtg Hole

Total No. of mtg.10 stud + 6 Bolt


Matching of Sub frame with Frame .

Assy SubFrame

Assy Frame


CTQ & CTP Drill-DownCTQ & CTP Drill-DownCritical to Quality

Critical customer

requirement

Customer issues

Voice of customer

DRL to be improved

Proper tightening of Bolt & Stud as per specification

Sub frame & Frame mismatch issues should be avoided.

Sub frame rework issues are very high in DRL.

Voice of business

Business issues

Critical business

requirement

Critical for processes

High customer dissatisfaction

Issues in finished vehicles to be eliminated

No mismatch issues

DPV 3.5 TO 1.0

Tips :1. Voice of customer and voice of business to be prioritized to those which are related to project objective2. Use VOB or VOC or both depending on the project objectives3. CTQ / CTP should be in NUT form (Name of the parameter, Unit of Measure, Target value)

DEFINE PHASE


What

What is the problem? Frame nut mismatch with Sub frame mtg hole

What has the problem? (part no, Lot no, etc.) Frame

What is the impact of the problem? (money, people, time, etc.)

High Rework impacts on time , Less Productivity, High DRL, Low Employee Moral, High Cost & Unsafe work.

Where

Where is problem located on Product/Part? Frame & Sub frame

Where does the problem occur in the process?

TCF Under Body Line St - 6

Where was the problem observed in the process? After Engine Stuffing with frame

When

When was the problem first noticed? From the first day of production

When has it been noticed since? Regular Basis

Who

Who is affected by the problem? Line operator

Who first observed the problem? Line Operator

To whom was the problem reported? Production / BIW

How

How much is the problem / impact of problem?

Line stoppages in TCF

How is the problem being rectified / corrected? Rework by grinding & tapping.

Problem Explanation (4W-1H)Problem Explanation (4W-1H)DEFINE PHASE


SIPOC DiagramSIPOC Diagram

Engine Stuffing

Sub-processes

DEFINE PHASE

Suppliers Inputs

BIW Sub Frame

Panse Frame

Engine Shop Engine Assy

TCF Engine Assy with Sub Frame

Outputs Customers

Finished Vehicle Final PDI

Assy Sub Frame Engine Assy On Sub Frame Body on Frame Engine Stuffing


Top Down ChartTop Down ChartDEFINE PHASE

Step-1 Step-2 Step-3 Step-4

Assy. Sub frame Engine Assy On Sub Frame

Body on Frame Engine Stuffing

Bush welding Assy. Side mbr LH & RH

Sub frame, Spring Coil & Lower Link loading on fixture Frame comes from Panse Body comes from U/B S.No-4 and Sub

frame with engine comes.

Rack & Pinion ,FRT X mbr , RR X mbr weld

Rack & Pinion , sub frame bkt & Power steering bottle fitment Assy U/ B weld with frame

Lift up sub frame up to frame height and sub frame hole match with frame nuts

SPM drilling (bush hole enlarge) FRT axle strut fitment Side wall , roof weld with frame Qualifying stud & bolt on sub frame mtg. nuts

Final inspection Engine loading & fitment on sub frame Door , L/B fitment & final inspection Torqueing done as per spec.

Send to Badve for powder coating Inspection engine with sub frame Comp. BIW send to paint shop

Sent to TCF Engine loading Body comes Mech. Line from Paint shop

Engine with sub frame unload on dolly Body comes U/B S. No. -5

Send dolly to U/B S. N.- 5

Act

iviti

es


Operational Definition Sl. No. Performance Indicator (Y) Operational Definition

Y1

Sub frame hole not centric with frame M10 nuts

Any mismatch of sub frame hole with frame nut defect which is visible to the bare. Mismatching defect may be one or more in number in a single Body but considered to be one single defective product.

Sl. No. Process / input Indicator (X) Operational Definition

X1 Assy. Sub frame welding Sub frame child part welding by MAG welding.

X2Complete BIW

To weld cabin with frame called BIW.

X3 Engine assy. On the S.F. To assemble Engine on the sub frame.

X4Engine stuffing When Engine Assembled sub frame matching with BIW

frame that’s called engine stuffing operation.

X5 Torqueing Tighten nuts as per spec. Called torqueing.

X6 Operator Name of the operator who matching sub frame with BIW frame.

X7

X8


PROCESS WALKTHROUGH (3G)

Final inspection Sub frame

Sub frame stage -2

Sub frame stage -1

Send to Badve for ED & paint

Engine Stuffing

U/B ST. N. -6

Mismatch Problem occurs

hereAssy. Frame

comes BIW -1c from supplier

Comp. BIW with frame

Send to Paint shop

Dropping TCF – 1C Mech. line

U/B ST. N. -5

Sub frame comes TCF from Badve

Engine Sub Assy.-1,2

&3

Engine loading on Sub frame

St. N. -4

Engine with sub frame inspection & send to U/ B line

Engine with sub frame loading

on Dolly

U/B ST. N. -7

U/B ST. N. -11Torqueing

U/B ST. N. – 1, 2 ,3 & 4


Area What Standard says? What is Observed? Photo / Sketch Potential Quick-

win opportunities

TCF 1CU/B LineStage -6

Proper matching of sub frame hole with Frame mtg. nuts

Sub frame hole mismatch with frame mtg. nuts.

(Sub frame mtg. hole not centric with frame nuts)

1.Sub frame mtg. hole (FRT STUD HOLE) cutting and nut tapping.

2. Frame old nut replace with new nut weld.

Process Walk Through (3G)Process Walk Through (3G)DEFINE PHASE


Quick-Win Selection & ImplementationQuick-Win Selection & Implementation

DEFINE PHASE

Q-Star Advance Project 24© Copyright, Confidential, Tata Motors Ltd24

FRAME

NO.

5949

FRAME

NO.5950

FRAM

ENO.5951

FRAM

ENO.5952

FRAMENO.5953

FRAME

NO.5954

FRAME

NO.5955

FRAME

NO.5956

FRAME

NO.5957

FRAMENO.5958

RESULT OK NOT OK

OK OK OK OK NOT OK

OK OK NOT OK

STUD IN A TAPPER WITH FRAME

FRAME

NO.

5959

FRAME

NO.5960

FRAM

ENO.5961

FRAM

ENO.5962

FRAMENO.5963

FRAME

NO.5964

FRAME

NO.5966

FRAME

NO.5967

FRAME

NO.5968

FRAMENO.5959

RESULT OK OK OK OK OK OK NOT OK

OK OK OK

Process Walk Through (3G)Process Walk Through (3G)


DEFINE PHASE

Area What Standard says? What is Observed? Photo / Sketch Potential Quick-win

opportunities

TCF U/BSTUD SHOULD BE QUALIFING PERPENDICULAR.

Nut welded with a taper due to no standard Welding process. Above

PROJECTION WELDING STARTED IN PLACE OF MAG WELDING.

BeforeBefore AfterAfter

Nut weld by MAG welding

Nut weld by Projection weldingStud not perpendicular

Process Walk Through (3G)Process Walk Through (3G)


MEASURE

What is the root cause?


Sub frame mtg. Hole mismatch

with frame in TCF

Unskilled manpower

Behavior

Irregular operator

Lack of awareness

Preventive maintenance of sub frame fixture

Process Sequence

not ok

WIS not followed

Tightening sequence not

ok

Frame Dim. Not ok

Sub frame Dim. Not okNut tapered on

frame

Fixture Resting block condition

MachineMan

Material Method

CAUSE AND EFFECT DIAGRAM

Environment

Improper Visibility

Improper Space


Prioritization of CausesPrioritization of Causes

Mismatch

101- Nut taper welded in frame 3 3

2- Sub frame dim. N.G. 9 9

3- Frame DIM. N.G> 9 9

4- Low tolerance of sub frame hole 9 9

5- Wrong vehicle resting pad 3 3

6- Preventive maintenance of fixture 3 3

7- Fixture clamp & block condition 3 0

8- Unskill manpower 0 0

9- Irregular operator 0 0

10- Lack of awareness 0 0

Effect >>

Importance >>Final Score

Cau

ses

Relationship Scale0 – No Relation, 1 – Week Relation, 3 – Moderate Relation, 9 – Strong Relation

MEASURE PHASE


Prioritization of CausesPrioritization of Causes

Mismatch

10

11- WIS not followed 3 3

14- Process sequence not followed 9 9

15- Tighting sequence not ok 0 0

16- Operator training 0 0

17- Improper visiblity 0 0

18- Improper space 0 0

Effect >>

Importance >>

Final Score

Cau

ses

Relationship Scale0 – No Relation, 1 – Week Relation, 3 – Moderate Relation, 9 – Strong Relation

MEASURE PHASE


Who wil lcollectethe data

How will the data be collected

How willthe databe used

How wil l the data be displayed

Instrument Type Make Srl no.Operating Range

Least count

Last ca l ibrated on

Next ca l i brati on due date

Methodto be used

No. of partsto be taken

No.of apprai sers(& Name)

No. of reading /part /appra iser

Acceptancecriteria

Resp.TargetDate

Attribute 50 3 1As per sheet

Pankaj 20/11/14

1-Anand

2-Gurdeep

3-Hargovind

SN.

Measurement system details Measurement system analysis plan

Performance measure(Ys /Xs)

OperationalDefinition

Data source

and location

Samplingmethodsample

size &Freq.

When will the data

be collected

Other data thatshould be collected

at the same time

MSA Plan

Data Collection Plan

MSA PLAN FOR CRITICAL DIMENSIONS AT BIW


MSAMSA

MEASURE PHASE

Date :-

Part:-

Part Type:-

Parameter:-

Specification:-

Part A-1 A-2 A-3 B-1 B-2 B-3 C-1 0.3 C-3 Ref. Value

1 1 1 1 1 1 1 1 1 1 12 1 1 1 1 1 1 1 1 1 13 1 1 1 1 1 1 1 1 1 14 1 1 1 1 1 1 1 1 1 15 1 1 1 1 1 1 1 1 1 16 1 1 1 1 1 1 1 1 1 17 1 1 1 1 1 1 1 1 1 18 1 1 1 1 1 1 1 1 1 19 0 0 0 0 0 0 0 0 0 0

10 0 0 0 0 0 0 0 0 0 011 1 1 1 1 1 1 1 1 1 112 0 0 0 0 0 0 0 0 0 013 1 1 1 1 1 1 1 1 1 114 1 1 1 1 1 1 1 1 1 115 1 1 1 1 1 1 1 1 1 116 1 1 1 1 1 1 1 1 1 117 1 1 1 1 1 1 1 1 1 118 1 0 0 1 0 0 0 0 0 019 0 0 0 0 0 0 0 0 0 020 1 1 1 1 1 1 1 1 1 121 0 0 0 0 0 0 0 0 0 022 1 1 1 1 1 1 1 1 1 123 1 1 1 1 1 1 1 1 1 124 1 1 1 1 1 1 1 1 1 125 1 1 1 1 1 1 1 1 1 1

Attribute Last Calibration:- NA

WELD SHOP DEFECTS Calibration Status:- OK

Anand Gurdeep Hargovind

5-Aug-14 Gauge: NA

NA Gauge No.:- NA

NA Calibration Frequency:- 6 MONTH

CROSS TABULATION METHODATTRIBUTE STUDY

26 1 1 1 1 1 1 1 1 1 127 1 1 1 1 1 1 1 1 1 128 0 0 0 0 0 0 0 0 0 029 1 1 1 1 1 1 1 1 1 130 1 1 1 1 1 1 1 1 1 131 1 1 1 1 1 1 1 1 1 132 1 1 1 1 1 1 1 1 1 133 1 1 1 1 1 1 1 1 1 134 1 1 1 1 1 1 1 1 1 135 0 0 0 0 0 0 0 0 0 036 1 1 1 1 1 1 1 1 1 137 0 0 0 0 0 0 0 0 0 038 1 1 1 1 1 1 1 1 1 139 0 0 0 0 0 0 0 0 0 040 1 1 1 1 1 1 1 1 1 141 1 1 1 1 1 1 1 1 1 142 1 1 1 1 1 1 1 1 1 143 1 1 1 0 0 1 1 1 1 144 0 0 0 0 0 0 0 0 0 045 0 0 0 0 0 0 0 0 0 046 1 1 1 1 1 1 1 1 1 147 0 0 1 0 1 1 0 0 1 148 0 0 0 0 0 0 0 0 0 049 1 1 1 1 1 1 1 1 1 150 1 1 1 1 1 1 1 1 1 1


MSAMSA

MEASURE PHASE0 1 0 139 1 40 38 2 40

10.93 29.07 40 10.40 29.60 402 108 110 1 109 110

30.07 79.933 110 28.60 81.40 11041 109 150 39 111 150

41.00 109 150 39.00 111 150P0 - Pe Po 0.98 P0 - Pe Po 0.981 - Pe Pe 0.61 1 - Pe Pe 0.61

Kappa 0.95 Kappa 0.95Miss Rate 2.564103False Alarm 1.80

0 1 0 139 2 41 38 3 41

11.21 29.79 41 10.66 30.34 412 107 109 1 108 109

29.79 79.207 109 28.34 80.66 10941 109 150 39 111 150


Kappa 0.93 Kappa 0.93Miss Rate 2.564103False Alarm 2.70

0 1 0 140 0 40 39 2 41

10.93 29.07 40 10.66 30.34 411 109 110 0 109 109

30.07 79.93 110 28.34 80.66 10941 109 150 39 111 150


Kappa 0.98 Kappa 0.97Miss Rate 0False Alarm 1.80

kappa kappa

Total Count Total Count Expected Count Expected Count

1 Count 1 Count Expected Count Expected Count

Ref valueTotal

A0 Count

C0 Count

Expected Count Expected Count

kappa kappa

A*C Cross Tabulation C

Total C*Ref Value Cross Tabulation


1 Count 1 Count Expected Count Expected Count

Ref valueTotal

B 0 Count

B 0 Count


kappa kappa

B*C Cross Tabulation C

Total B*Ref Value Cross Tabulation

1 Count Expected Count Expected Count


A0 Count

A0 Count


1 Count

A*B Cross Tabulation B

Total A*Ref Value Cross Tabulation Ref value

Total


MSAMSA

MEASURE PHASE

CONCLUSION :

Target A B Ckappa > 0.75 0.95 0.93 0.97

Miss Rate Max 2% 2.56 2.56 0.00False Alarm Max 6% 1.80 2.70 1.80

0.98 0.97 0.990.03 0.027 0.020.03 0.000 0.00

EffectivenessPfaPM


DEFECT CONTRIBUTION

34

2

1

3

1

2

3

S.N. PROBLEM %

1 FRT STUD 60%

2 CENTER STUD 10%

3 JACK MTG 30%

MEASURE PHASE


I

SUB FRAME DIM SPECIFICATION

B 826

C 710

D 50

E 50

F 50

G 80

H 974

I 761

B

A

D

C

FG

E

H

Points DimensionA 710

MEASURE PHASE


SUB FRAME DIM MEASUREMENTSUB FRAME DIM MEASUREMENT

MEASURE

POINT

SPEC.

SB

NO.

93715

SB

NO.

93716

SB NO.

9371

7

SB NO.

9371

8

SBNO.93719

SBNO.93720

SBNO.9372

1

SBNO.9372

2

SBNO.9372

3

SBNO.

93724

A 710 708 709 707 708 709 707 709 708 706 707

B 826 824 823 425 826 825 824 825 823 824 824

C 710 710 710 709 708 709 710 709 710 708 709

D 50 49 51 50 50 49 50 49 50 50 50

E 50 50 50 49 50 50 49 49 50 50 49

F 50 50 49 50 50 50 50 50 49 50 50

G 80 79 80 79 80 80 80 80 80 79 80

H 974 972 971 973 972 974 973 972 972 973 973

I 761 761 760 761 759 759 758 758 759 759 758

I

B

A

D

C

F

G

E

H

ALL DIM MEASURED IN mm BY MEASURING TAPE .ALL DIM MEASURED IN mm BY MEASURING TAPE .


1st Step : -CMM Report Part Level (Before )

MEASURE & ANALYZE PHASE


FRAME SPECIFICATION

H

BA

D

C

F

G

E

B 826

C 710

D 50

E 50

F 50

G 80

H 974

Points DimensionA 710

MEASURE


FRAME OBSERVED DATA


POINT

SPEC.

FRAME

NO.

570

7

FRAME NO.5708

FRAMENO.5709

FRAMENO.5710

FRAMENO.5711

FRAMENO.5713

FRAMENO.5714

FRAMENO.5715

FRAMENO.5716

FRAMENO.5718

A 710 710 711 713 712 712 711 712 712 711 712

B 826 825 823 424 826 824 823 824 824 823 824

C 710 709 708 709 708 709 708 708 709 710 709

D 50 50 49 50 50 49 50 49 49 50 50

E 50 50 48 49 50 50 49 49 50 49 48

F 50 50 49 50 50 50 50 50 50 50 50

G 80 79 80 79 80 80 80 80 80 80 80

H 974 974 977 975 978 977 976 975 976 975 975

A BC

D

E F

G

H


4040

S.NO. POINT NO. AXISNOMINAL

LHNOMINA

L RHERROR LH ERROR RH ERROR LH ERROR RH

X -78 -78 -0.58 -1.61 -0.84 -0.75

A Y -355 355 0.26 0.6 0.11 0.66

Z -102.5 -102.5 -0.79 1.04 -1.23 -2.21

X 285 285 -0.59 -1.7 -1.59 -2.23

B Y -355 355 -1.45 -1.22 1.03 0.84

Z -110.5 -110.5 -2.88 -0.81 -0.84 -3.82

X 507.5 507.5 0.69 -2.81 -1.29 -2.35

C Y -355 355 -2.41 -1.77 0.27 -0.52

Z -122.5 -122.5 -3.16 -1.01 -3.44 -3.46

X 587.5 587.5 -0.23 -1.76 -2.19 -2.83

D Y -355 355 -1.92 -2.01 0.15 0.06

Z -122.5 -122.5 -3.59 -1.66 -3.66 -3.68

X 91 91 -1.2 -2.48 -1.75 -1.52

8 Y -412.95 412.95 -2.44 1.88 -2.23 2.83

Z -102.5 102.5 -1.38 0.67 -3.19 -2.7

X 507.5 507.5 -1.38 -2.59 -1.62 -2.56

9 Y -304.72 405.28 -1.59 -2.14 0.26 0.2

Z -122.5 -122.5 -4.57 -1.1 0.96 -0.28

X 587.5 587.5 -1.59 -1.58 -1.1 -1.55

10 Y -304.72 405.28 -1.48 -2.54 2.35 -1.99

Z -122.5 -122.5 -2.97 -2.05 0.37 -1.14

X -78 -78 -0.88 -2.11 -1.29 -2.55

11 Y -304.66 -304.66 1.62 -2.94 1.44 -3.16

Z -102 -102 0.39 0.57 -1.91 -0.92

SUPER ACE FRAME CMM REPORT P1423822 (14.08.2014)P1422978

(06.08.2014)

6

8

4

1

7

2

SUB FRAME MTG

3

5

Frame CMM Report


Analyze & Improve


Why –Why 1: Sub frame hole mismatch with frame nut

Why –Why 2: Position of holes in sub frame shifted

Why –Why 3: Sub frame dimension not ok as per CMM

Why –Why 4: Position of locating pin shifted in Sub frame welding fixture.

42

Root Cause:- Locating pin shifted

in Sub frame welding fixture

WHY WHY ANALYSIS - 1


LH side bkt position shifted in +Y dir by 2.0 mm.

RH side bkt position shifted in +Y dir by 2.0 mm.

Correction on Side member for Sub frame mtg at M/S Autoline

IMPROVE PHASE


Jack Mtg. Hole position LH shifted in +Y direction by 2.0 mm

Correction on Assy subframe at BIW 1CJack Mtg. Hole position RH shifted in +Y

direction by 2.0 mm

IMPROVE PHASE


45

CMM Report Part Level ( After )

IMPROVE PHASE


46

LH side bkt position corrected in X dir by +2.0 mm.RH side bkt position corrected in X dir. By

– 2.0 mm

LH side bkt position corrected in X dir by -2.0

mm.RH side bkt position corrected in X dir. By

+ 2.0 mm

LH side bkt position corrected in X dir by 2.0 mm.

RH side bkt position corrected in X dir. By

– 2.0 mm

Correction on frame at Supplier

IMPROVE PHASE


47

LH side bkt position corrected in X dir by 2.0 mm.

RH side bkt position corrected in X dir. By

– 2.0 mm

Correction on frame Jack Mtg. point at Supplier

IMPROVE PHASE


4848

CMM Report Frame (After Improvement)

S.NO. POINT NO. AXISNOMINAL

LH NOMINAL RHERROR LH ERROR RH ERROR LH ERROR RH

X -78 -78 -0.2 -0.66 0.49 0.17

A Y -355 355 0.84 -0.55 1.15 1.03

Z -102.5 -102.5 1.19 1.94 0.57 1.04

X 285 285 -0.08 -1.19 0.54 -0.01

B Y -355 355 -0.29 -0.35 0.13 0.81

Z -110.5 -110.5 0.04 -0.61 -1.75 -0.69

X 507.5 507.5 0.21 -1.01 0.31 -0.33

C Y -355 355 -1.28 -0.74 -1.45 0.5

Z -122.5 -122.5 -0.54 2.35 0.02 -1.32

X 587.5 587.5 0.32 -1.01 -0.01 -1.03

D Y -355 355 -0.75 0.11 -1.1 0.77

Z -122.5 -122.5 1.62 -0.94 -0.36 -1.71

X 91 91 0.2 -1.45 0.33 -1.03

8 Y -412.95 412.95 -1.89 1.1 -1.06 0.74

Z -102.5 102.5 0.51 1.47 0.35 0.47

X 507.5 507.5 0.11 0.56 0.7 -0.85

9 Y -304.72 405.28 -0.39 1.03 -0.88 0.83

Z -122.5 -122.5 1.94 1.37 1.47 -1.89

X 587.5 587.5 0.36 -1.58 0.58 -1.02

10 Y -304.72 405.28 -0.33 0.09 -1.25 1.12

Z -122.5 -122.5 0.77 0.31 -1.87

X -78 -78 -0.6 -0.73 0.51 -1.54

11 Y -304.66 -304.66 1.26 -1.06 1.27 -1.2

Z -102 -102 1.35 -0.81 2.55 1.05

6

7

8

3

4

5

P1426791 (05.09.2014) P1427105 (10.09.2014)

1

SUB FRAME MTG

2

SUPER ACE FRAME CMM REPORT P1426791 (11.8.14) P1427105(14.8.14)

Q-Star Advance Project 49© Copyright, Confidential, Tata Motors Ltd 49

IMPROVE PHASE


Why –Why 1: Sub frame hole mismatch with frame nut

Why –Why 2: Sub frame twisted during coil spring fitment.

Why –Why 3: Gap observed B/W resting block and sub frame during coil spring fitment process.

Why –Why 4: Resting block wear out.

50

Root Cause:- Sub frame twisted due to resting block wear

out.


Why –Why 4: Check point not availed for resting block condition in JH sheet.


51

DEVELOPMENT OF SOLUTION

710MM

705 MM

Before fitment of coil spring DIM

After fitment of coil spring

Coil spring fitment with Sub Frame


SUB FRAME DIM 710mmSUB FRAME DIM 710mm


ALL DIM MEASURED IN mmALL DIM MEASURED IN mm


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Resting block wear out leads to sub frame twisting

New resting block installed

DEVELOPMENT OF SOLUTION


IMPROVE PHASE


Why –Why 1: Sub frame hole mismatch with frame nut.

Why –Why 2: Sub frame long mbr twists after engine stuffing operation due to high twisting moment .

Why –Why 3: Weight of Sub frame-engine assembly concentrated only on 2 studs

Why –Why 4:Assembly mounted with only 2 studs before rest of the studs/bolts are mounted.

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Root Cause:- Twisting of sub frame during engine stuffing

due to the use of only 2 studs during the initial mounting

process.


Why –Why 5: Insufficient gap for stud qualifying B/W Engine stuffing bed and sub frame.


SUB FRAME ASSY PROCESS SEQUENCE (BEFORE)

Two Center Stud (LH/ RH) used to mount the engine carrying sub frame

Mounting of remaining 8 studs and 6 bolts was done after the engine stuffing process.


SUB FRAME ASSY PROCESS SEQUENCE (AFTER)

2 Center studs+ 4 JACK Mtg studs+ 4 FRONT Studs (LH/RH) are now mounted before the engine stuffing operation.

Remaining 6 bolts are mounted after the engine stuffing process.


CURRENT STATUS (AFTER IMPLEMENTATION)


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Improvement

Now stud qualifying is done before engine stuffing


Improvement

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BEFORE

AFTER

Hole side increase 13 mm to 16mm


Improvement

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BEFORE

AFTER

Sub frame Panel Side member LH hole size increase 11 mm to 12.5 mm


Improvement

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BEFORE

AFTER

Sub frame Panel Side member RH hole size increase 12.5 mm to 14.0mm


IMPROVE PHASE


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TARGET ACHIEVEDSub Frame Rework % after improvement

IMPROVE PHASER

ewor

k in

%


Control


Hard Control

Soft Control

• Frame critical DIM. Inspection Gauge made.• Frame critical DIM. Inspection Gauge made.• Calibration of welding fixture done• Trolley modification done to avoid transit damage.

• Work Instruction Updated & display in shop floor • Check point added in JH sheet for resting block condition.• Die spotting & polishing frequency revised & added in Die History card• On job training provided to operators for Proper matching sub frame with frame.

Way of Control Mechanism

CONTROL PHASE


STANDARDISATION

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इसी प्रकार सेंट्रल स्टड 2 + Front stud 4 मे भी SMALL SIDE को बॉडी के INTERNAL THREAD पर PNEUMATIC GUN से टाइट करें LH & RH

अब 4 JACK माउंट स्टड को भी इसी प्रकार SMALL SIDE से बॉडी पर नऊमॅटिटक गुण दुवारा फि"ट करें

CONTROL PHASE


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CONTROL PHASEJH CHECK SHEET


BEFORE AFTER

There was No gauge for checking sub frame dimension 710mm.

Now we have gauge for checking sub frame dimension 710mm.

BENEFITS:- Zero Rework , Quality improve , Cost & moral.

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No Gauge for checking sub frame dimension.

CONTROL PHASE


BEFORE AFTER

There was No gauge for checking frame dimension 710mm.

Now we have gauge for checking frame dimension 710mm.

BENEFITS:- Zero Rework , Quality improve , Cost & moral.

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No Gauge for checking frame dimension.

CONTROL PHASE


Frame to be check on checking fixture from supplier end.

CONTROL PHASE


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4 TIMES / SEASON

BENEFITS

Tangible Benefits:-

We save rework manpower (2 in nos.) cost of 30000Rs. per month 30000 *12 (month)= 3,60,000 Rs. p.a.

4 Taps & 1 Conical bit per day (670Rs.) = 17420Rs. per month 17420* 12 (month) = 2,09,040 Rs. p.a.

4 Drill bits Cost per day (4900Rs.) = 127400Rs. per month 127400 * 12 = 15,28,800 Rs. p.a.

Total Amount = 20,97,840 Rs. Per annum

Cost saving of Rs 20.97 Lacs/ annum


Eliminate customer complain.

Improved presentation skill.

Improved analytical knowledge.

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Intangible Benefits:-

BENEFITS

Knowledge about 6 Sigma tools.

Improved team work & self confidence.


YOUR ARE

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six sigma project final

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