Keywords: six sigma; foundry SMEs; small and medium-sized enterprises; design of experiments; DOE; measurement system analysis; MSA; failure mode and effects analysis; FMEA; non-conforming products; cost of poor quality; hypothesis testing; defects per million opportunities; DPMO; process capability; DMAICS; analysis of variance; ANOVA; India; make-to-order foundries; scrap reduction; productivity.

1. x
SIX SIGMA
FOUNDRY MATERIAL SCRAP REDUCTION
3.9L PISTON
BY
DR. BIKRAM JIT SINGH
PROFESSOR
GREEN BELT
MMDU MULLANA
MARCH 28TH 2007

2. x
BUSINESS CASE
In April 2006, started in the Automotive Business Unit the new part number production (81124,
3.9L piston). The foundry material scrap was 7.0% in average.

3. x
OBJECTIVE
Reduce the foundry material scrap from 7.0% at 2.0%
maximum, in a 4 months period, with the following benefits:
-Cost reduction
-More machining lines availability
-Less scrap re-melting
-Less customer complains
-$128,510.00 USD Annual savings

4. x
PROJECT SCOPE
In Scope: Run tests only with one dies serie (69 - 72), in order to
finish in the 4 months period established. After that the rest of the
dies (6 more series) will be modified according with the
improvement (6 months more).
Out of Scope: Other part numbers (4.8L, 5.3L, Polaris, Tecumseh
and HD Skirts)
Start: July 21st 2006
Stop: 1st Goal  5% Week 37
2nd Goal  3.5% Week 42
3rd Goal  2.0% Week 46

5. x
GOAL STATEMENT
Y= %Foundry material scrap pistons (Porosity).
X1: Pouring speed
X2: Robot ladles alignment
X3: Die design
X4: Top core design
X5 Ingate design
X6: Robot ladle cleanness
X7: Degassing
X8 Flux treatment

6. x
OTHER BENEFITS
More Foundry equipment availability
More Machining line availability
Less Customer complains (Machining, Phosphate,
Assembly and GM).

7. x
6 SIGMA MAP ROAD OF PROJECTPerformance
GOOD
BAD 3 Sigma
6 Sigma
Six Sigma
Discovering
Sustain
Start: 16/Nov/06
Finish: Permanent
Improve
Start: 13/Sep/06
Finish: 11/Oct/06
Control
Start: 12/Oct/06
Finish: 15/Nov/06
Analyze
Start: 17/August/06
Finish: 12/Sep/06
Measure
Start: 20/Ju/06
Finish: 16/Aug/06
Define
Start: 06/Jun/06
Finish: 21/Jul/06

8. x
PROJECT CHARTER
Foundry Material Scrap Reduction, 3.9L Piston
Green Belt: Víctor Espejo
Reduce the foundry material scrap from 7% (9,030 pistons/month) to 2%
max. (2,500 pistons/month), in 4 months.
Cost reduction and more machining line availability.
The piston cost = 1.64 USD/piece.
Total savings per year = $128,510 USD
Measurements / Objective / Target
- Identify the defect
- Scarp Mapping (identify the zones)
- Review the ingate system
- Magma modeling simulation
- Design a new ingate system and run with Magama
modeling.
- Modify the ingate system
- Test with proposal # 1
- Test with proposal # 2
- Choose the best ingate system for Puebla process
Key Actions
In April 2006 started the new part number production
(81124, 3.9L piston), The material scrap rate average
after machining is 7%.
Monthly production average is 129,000 pistons.
• Foundry Material
Scrap Reduction,
3.9L Piston
Current SituationProject
Reduce the foundry material scrap from 7% (9,030 pistons/month) to 2%
max. (2,500 pistons/month), in 4 months.
Cost reduction and more machining line availability.
The piston cost = 1.64 USD/piece.
Total savings per year = $128,510 USD
Measurements / Objective / Target
- Identify the defect
- Scarp Mapping (identify the zones)
- Review the ingate system
- Magma modeling simulation
- Design a new ingate system and run with Magama
modeling.
- Modify the ingate system
- Test with proposal # 1
- Test with proposal # 2
- Choose the best ingate system for Puebla process
Key Actions
In April 2006 started the new part number production
(81124, 3.9L piston), The material scrap rate average
after machining is 7%.
Monthly production average is 129,000 pistons.
• Foundry Material
Scrap Reduction,
3.9L Piston
Current SituationProject
Current ResourcesObstacles for
success:
4 Months
Implementation Time
£ 4,520.00
Only for two die blocks series for the test
Total 7 series (5 series for improvement
implementation)
Resources / Costs for Implementation
See team members chart
$
Members required for
implementation
Difficult
Grade
Impact
Value
Current ResourcesObstacles for
success:
4 Months
Implementation Time
£ 4,520.00
Only for two die blocks series for the test
Total 7 series (5 series for improvement
implementation)
Resources / Costs for Implementation
See team members chart
$
Members required for
implementation
Difficult
Grade
Impact
Value
Priority:

9. x
PROCESS MAP CONSTRUCTION
Step 5:
F
A B B,C C D E
J,K,L I
H G
Steps
10.- Die preparation Input Classification
20.- Ingots transportation to foundry Critic
30.- Ingots storage (in Cell) Controlled
40.- Furnace charge Noise
50.- Melting
60.- Degassing and flux treatment A.- Die coating
70.- Holding time and impurity flotation B.- Furnace charge relation
80.- Start up casting cell machine C.- Molten metal temperature
90.- Pouring D.- Density Index (ID)
100.- Croppers E.- Cycle time
110.- AQFD F.- Pouring speed
120.- Visual inspection and baskets accommodation G.- AQFD
130.- Storage before heat treatment H.- Without visual defects
140.- Heat Treatment I.- Aging
150.- Q.A. Release J.- Microstructure
160.- Transportation to release material area K.- Hardness
170.- Storage before machining L.- Chemical analysis
Write Down and Classify the Key Process Input
CTQ's
10 20 30 40 50 60
ID=1,5 max.
Si
No
70
80 90
100
110120130
Si
No
Scrap
130140150
Si
No
Scrap
160
170
Die temperature
Die coating density
Spray gun
Free of humidity
Free of slag
Charge relation
(60 Ingot /40 scrap)
Temperature
Metal Temp.
N2 Flow
RPM
Time Time
Water cooling
system
Cycle time
Pouring speed
Ladle cleaning
Metal temperature
Die Coating
Water cooling time
Water coling temp.
Ingate separation
AQFD
Free of visual
defects
Separate in baskets by
cavity
Temperature
Time
Chemical Analysis
Microstructure
Hardness
Q.A. Release card
10 20 30 40 50 60
ID=1,5 max.
Si
No
70
80 90
100
110120130
Si
No
Scrap
130140150
Si
No
Scrap
160
170
10 20 30 40 50 60
ID=1,5 max.
Si
No
70
80 90
100
110120130
Si
No
Scrap
130140150
Si
No
Scrap
160
170

10. x
PROCESS MAP CONSTRUCTION
Step 7:
F
A B B,C C D E
J,K,L I
H G
Ingots transportation to foundry
Pistons waiting for heat treatment
Heat treated pistons transportation
Pinstons stock for machining
Steps with out value
10 20 30 40 50 60
ID=1,5 max.
Yes
No
70
80 90
100
110120130
Yes
No
Scrap
130140150
Yes
No
Scrap
160
170
Die temperature
Coating Density
Spray gun
Free of humidity
Free of slag
Charge relation (60%
Ingot / 40% scrap)
Temperature
Metal Temp.
N2 Flow
RPM
Time Time
Water cooling
system
Cicle time
Pouring speed
Ladle cleanning
Metal temperature
Die coating
Water cooling time
Water cooling temp.
Ingate separation
AQFD
Free of defects
Separate in baskets per
cavity
Temperature
Time
Chemical Analysis
Microestructure
Hardness
Q.A. Release card

11. x
1,2%
1,0% PIEZAS 12789
BASE 9´05 DIC ' 05 SEM 23 SEM 24 SEM 25 SEM 26 SEM 27 PR/SEM ACUM.
8.601 36.501 50.075 34.706 53.764 0 35.009 175.046
495 2.625 3.291 2.076 4.797 0 2.558 12.789
5,44% 6,71% 6,17% 5,64% 8,19% #¡DIV/0! 6,81% 6,81%
[#] [PCS] [#] [PCS]
1 11430 8 0
2 889 9 0
3 381 10 0
4 54 11 0
5 16 12 0
6 14 13
SCRAP [%] OBJETIVO 7 5 14
1,2%
1,0%
BASE 9´05 ENE ' 06 FEB ' 06 MAR ' 06 ABR ' 06 MAY ' 06 JUN ' 06
8.601 39.063 175.046
495 3.351 12.789
5,44% 7,90% 6,81%
SCRAP [%] OBJETIVO
ACUM.
214.109
16.140
7,01%SCRAP [%]
SCRAP DE FUNDICION EN MAQUINADO
SCRAP DE FUNDICION EN MAQUINADO 6,81%
RECHAZO
[PZAS]
SCRAP [%]
PROD. NETA OK
[PZAS]
RECHAZO
[PZAS]
PROD. NETA OK
[PZAS]
@SEM 26
JUNIO '2006
INCLUSIONES
GOLPES
PINTURA
PROBLEMA
SCRAP EN FOSFATO
PIP DAÑADO
GAS
RECHUPES (Gate)
REBABA O FLASH
AIRE ATRAPADO
OXIDOS
RECHUPES (Back)
METAL PEGADO
SCRAP DE FUNDICION EN MAQUINADO
81124 (3,9L)
PROBLEMA
PARETO DE RECHAZOS
META @ JUN' 06
META @ DIC' 05
META @ JUN' 06
META @ DIC' 05
5,44%
6,71%
6,17%
5,64%
8,19%
0,00%
6,81%
0,0%
1,0%
2,0%
3,0%
4,0%
5,0%
6,0%
7,0%
8,0%
9,0%
10,0%
BASE 9´05 DIC ' 05 SEM 23 SEM 24 SEM 25 SEM 26 SEM 27 PR/SEM
11430
889
381 54 16 14 5 0 0 0
89%
96%
99% 100% 100% 100% 100% 100% 100% 100%
0
2000
4000
6000
8000
10000
12000
14000
84%
86%
88%
90%
92%
94%
96%
98%
100%
102%
5,44%
7,90%
6,81% 7,01%
0,0%
2,0%
4,0%
6,0%
8,0%
10,0%
BASE 9´05 ENE ' 06 FEB ' 06 MAR ' 06 ABR ' 06 MAY ' 06 JUN ' 06 ACUM.
New piston 3,9L (81124)
Foundry Material Scrap Pareto
3.9L Piston (81124)

12. x
5M DIAGRAM
Method Medio ambiente (Enviroment) Materials
Turbulence during pouring High humidity Dirty ingots from supplier
Pouring interrupted Water leaks on dies Metal temperature too high
Ladel drying Too much dust in the building Liquid metal level high, it touch the furnace iron ring
Aluminum in the pouring bush Metal contamination from ceramic fiber from the lids
Poor molten metal treatment Poor scrap conditions from other areas
Poor ladle cleaning
Incorrect molten metal surface skimming
Slow pouring speed
Molten metal regassing
Ladle alignment
Manpower Machinery
Poor metal cleaning practices Dirty ladle during pouring
Furnace lids are open all the time Ingate width too wide
Poor die coating conditions on cell Die design
Poor piston defects inspection Ingate design
Die conditions
Deskulling box in bad conditions
Dirty crucibles
Robot aborts
Top core design
Poor die venting
Turbulence during metal transportation (robot)
Robot scooping during ladle filling
Foundry Material Scrap
(3.9L Piston)

13. x
CAUSE – EFFECT MATRIX (80/20)
Critic
Control
Noise
10 8 6 5 3 4 3 3 3
2 3 4 5 6 7 8 9 10
AirBubbles
Misrun
Weeping
Coating
HitandDamages
pipdamage
Hydrogen
porosity
Warmers
Shrinkage
Total
Process Step Process Input
11 Set up Die coating 7 8 4 10 6 8 9 283
5 Set up Die preheating 8 9 8 8 216
14 Set up Water cooling connections 5 8 9 6 8 210
1 Pouring Low pouring speed 10 8 5 179
2 Design Ingate 10 7 6 174
10 Pouring Water cooling temperature too low 7 10 7 171
3 Pouring Water cooling time too short 9 9 7 165
18 Pouring Ladles alignment 9 7 6 164
8 Pouring Molten metal temperature too low 8 8 6 162
13 Design Blocks and cores 6 6 4 6 150
9 Pouring Water cooling temperature too high 8 8 7 149
15 Pouring Water cooling time too long 4 10 8 144
6 Pouring Molten metal temperature too high 8 6 5 4 143
4 Design Top core 9 5 6 128
Total
1310
728
270
90
18
76
87
171
237
3108
Correlation of Input to Output
Rating of Importance to Customer
Characteristic
Cause and Effect Matrix
for Foundry

14. x
AMEF Numero:
FD
60
Pouring
High Pouring
speed
Over pour,
incomplete
pieces, down
time
4
Wrong robot
adjustment
during pouring
4
Password to
robot program
Visual 6 96
New
passwords
controlled only
by team
leaders
O. Cruz
Week 34 2006
Set new
passwords
4 2 6 48
FD
60
Pouring
Low pouring
speed
Turbulences 4
Wrong robot
adjustment
during pouring
4
Password to
robot program
Visual 6 96
New
passwords
controlled only
by team
leaders
O. Cruz
Week 34 2006
Set new
passwords
4 2 6 48
FD
60
Pouring
Ladles
disalignment
Over pour,
incomplete
pieces, down
time,
turbulences
4
Wrong robot
ladles
adjustment,
wrong robot
adjustment
during metal pick
up and pouring
3
Robot
alignment every
ladles change
and set the
password to the
program
Visual 6 72
Device to verify
ladles
alignment and
height after
maintenance
R. Avila
Week 38 2006
FD
60
Pouring Ingate design
Porosity by air
trapped and
oxides
6
Air aspiration
and turbulences
3
Verify scrap
after machining
7 126
Magma
simulation for
new designs
Víctor Espejo
Week 38 2006
Modify tooling
with supplier
6 1 4 24
FD
60
Pouring
Robot arm
disalignment
Over pour,
incomplete
pieces, down
time
4
Robot arm
disalignment,
screw loose and
robot crash
4 Visual 7 112
Screw
adjustments
every PM
J. López
Week 36 2006
Robot PM
every month
(program)
4 3 6 72
N. P.
R.
Actions
recommended
Responsible y Due
date
Action done results
Action done
S
E
V
O
C
U
D
E
T
N
P
R
O
C
U
R
Current Process
Controls
PREVENTION
Current Process
Controls
DETECTION
D
E
T
Nombre de Parte / Descripción
GM 5.3L Fijo, GM 3.5L, GM 5.3L Perno Flotante, GM 3.9L, GM 4.8L; TECUMSEH
Ref.
No.
Process
description
Failure Mode
Effect potential
failure
S
E
V
C
L
A
S
E
Cause / Mechanism
Potential Failure
Numero de Parte / Ultima versión del cambio Equipo Central Otras Aprobaciones / Si es necesario
81030C(5.3L GM)
81063C(3.5L GM)
81064G(5.3L Flot GM)
81124 (3.9L GM)
81094 (4.8L GM)
80094 (Tecumseh)
B2
R005
R005
R001
R003
R C
V. Espejo, O. Cruz, M. Hernández,E. Miranda, O. Rodríguez, R.
Avila, A Farfan.
No. de revisión
Eric Miranda M. (222) 4043100 ext 210 13-Jul-02 07-Ago-06 11AMFD-01
Contacto / No. Telefono Fecha (Emisión) Fecha (Rev.)
FAILURE MODE EFFECT ANALYSIS
( PROCESS FMEA )

15. x
Capability Study
Automatic Sigma Calculator
Attribute Data
Total Defects 2768
# of opportunities 3
Total units 26255
These are your defects
(dpmo) 35143
These are the DPU 0,1054 232,6
Zbench 3,3101 This is the value of sigma in your process
Entitlement (defects) 18
Color code Not capable
Borderline
Capable
Air Trapped (90%) Oxide (7%) Shrinkage (3%)
Scrap 2768 2491 194 83 2768
Machined parts 26255
%Scrap 10.5%
Production Results Week 32

16. x
% Appraiser
0,0%
10,0%
20,0%
30,0%
40,0%
50,0%
60,0%
70,0%
80,0%
90,0%
100,0%
110,0%
Zully "Q.A." 0 0
%Efficiency
95% UCL
Calculated Score
95% LCL
% Score vs Appraiser
0,0%
10,0%
20,0%
30,0%
40,0%
50,0%
60,0%
70,0%
80,0%
90,0%
100,0%
110,0%
Zully "Q.A." 0 0
%Efficiency
95% UCL
Calculated Score
95% LCL
Measurement System Evaluation

17. x
Hypothesis Test
Datas Type:
Continuous
X1 Pouring speed (Fast and slow) *Discrete
X2 Ingate design (Ingate area, only 2 sizes) **Discrete
X3 Ladle alignment (Alignment and Not alignment) Discrete
X4 "Top Core" Design (Modified and Not modified) Discrete
Ho Not relation, Not difference
Ha Relation, Difference
* Pouring speed from 3,00 sec to 4,50 sec.
** Ingate areas average: 135 mm 2
y 165 mm 2
Critics X's for Y's
% Machining pistons with foundry defects
(Porosity)
Y

18. x
Hypothesis 1:
1.- The feeding area in the dies (“Ingates”), affect to the scrap by
porosity, the ingates are not well calculated in the design.
Y = % Scrap after machining (Foundry porosity). (Continuous)
X = Ingate design (Feeding area: 135mm2 y 165mm2). (Discrete)
Ho = There is not relationship between ingate design and % scrap
Ha = There is relationship between ingate design and % scrap 300 pistons per cavity
130 - 140 160 - 170
69 8.4% 12.2%
70 8.4% 20.9%
71 2.8% 11.0%
72 3.4% 10.4%
69 9.7%
70 8.0%
71 4.2%
72 11.1%
Cavity
Area (mm2)

19. x
%Scrap
Percent
2520151050-5
99
95
90
80
70
60
50
40
30
20
10
5
1
Mean 9,688
StDev 5,664
N 8
AD 0,371
P-Value 0,328
Probability Plot of %Scrap
Normal
Area
95% Bonferroni Confidence Intervals for StDevs
165
135
2520151050
Area
%Scrap
165
135
2015105
Test Statistic 0,39
P-Value 0,461
Test Statistic 0,02
P-Value 0,902
F-Test
Levene's Test
Test for Equal Variances for %Scrap
Hypothesis Test. One Way Anova.
Ingates Design Vs %Scrap
Data
Area 165Area 135
20
15
10
5
Individual Value Plot of Area 135; Area 165
Data
Area 165Area 135
20
15
10
5
Boxplot of Area 135; Area 165

20. x
One-way ANOVA: Area 135; Area 165
Source DF SS MS F P
Factor 1 124,0 124,0 7,40 0,035
Error 6 100,5 16,8
Total 7 224,5
S = 4,093 R-Sq = 55,24% R-Sq(adj) = 47,78%
Individual 95% CIs For Mean Based on
Pooled StDev
Level N Mean StDev ---------+---------+---------+---------+
Area 135 4 5,750 3,070 (----------*---------)
Area 165 4 13,625 4,907 (---------*---------)
---------+---------+---------+---------+
5,0 10,0 15,0 20,0
Pooled StDev = 4,093
Hypothesis Test. One Way Anova.
Ingates Design Vs %Scrap
Conclusion: Discard Ho, Accept Ha.

21. x
Hypothesis 2:
2.- The robot ladles alignment to pour metal into the dies, affect the
scrap rate, should be alignment respect to the pouring bush.
Y = Foundry material scrap (Foundry porosity). (Continuous)
X = Ladles alignment (Alignment and non alignment). (Discrete)
Ho = There is not relationship between ladles alignment and % scrap
Ha = There is not relationship between ladles alignment and % scrap
300 pistons per cavity
Alignment Non Alignment
69 0.00 5.43
70 0.63 5.00
71 2.03 3.60
72 1.53 3.00
69 0.70 2.12
70 2.20 3.53
71 1.25 1.22
72 0.00 0.75
Robot Ladles (%Scrap)
Cavity

22. x Hypothesis Test. One Way Anova.
Ladle Alignment Vs %Scrap
%Scrap A.
Percent
6543210-1-2
99
95
90
80
70
60
50
40
30
20
10
5
1
Mean 2,062
StDev 1,657
N 16
AD 0,422
P-Value 0,283
Probability Plot of %Scrap A.
Normal
Alineacion
95% Bonferroni Confidence Intervals for StDevs
1
0
4,03,53,02,52,01,51,00,5
Alineacion
%Scrap A.
1
0
6543210
Test Statistic 0,26
P-Value 0,096
Test Statistic 2,82
P-Value 0,115
F-Test
Levene's Test
Test for Equal Variances for %Scrap A.
Data
No AlineadoAlineado
6
5
4
3
2
1
0
Boxplot of Alineado; No Alineado
Data
No AlineadoAlineado
6
5
4
3
2
1
0
Individual Value Plot of Alineado; No Alineado

23. x
One-way ANOVA: Alineado; No Alineado
Source DF SS MS F P
Factor 1 16,63 16,63 9,48 0,008
Error 14 24,56 1,75
Total 15 41,18
S = 1,324 R-Sq = 40,37% R-Sq(adj) = 36,11%
Individual 95% CIs For Mean Based on
Pooled StDev
Level N Mean StDev +---------+---------+---------+---------
Alineado 8 1,043 0,850 (--------*-------)
No Alineado 8 3,081 1,669 (--------*-------)
+---------+---------+---------+---------
0,0 1,2 2,4 3,6
Pooled StDev = 1,324
Hypothesis Test. One Way Anova.
Ladle Alignment Vs %Scrap
Conclusion: Discard Ho, Accept Ha.

24. x
Hypothesis 3:
3.- A Top Core modification to increase the material in the crown to be
eliminated in the machining line, will be to decrease the scrap porosity around
the pockets.
Y = Foundry material scrap (Foundry porosity). (Continuous)
X = “Top Core” Design (Modified and Non modified). (Discrete)
Ho = There is not relationship between “Top Core” design and % scrap
Ha = There is relationship between “Top Core” design and %scrap
300 pistons per cavity
Modified Non Modified
1.18 3.00
0.51 1.90
4.17 1.27
1.75 1.20
1.19 1.90
2.82 4.56
5.71 5.40
Top core
Cavity (69)

25. x Hypothesis Test. One Way Anova.
Top Core Design Vs %Scrap
%Scrap top
Percent
76543210-1-2
99
95
90
80
70
60
50
40
30
20
10
5
1
Mean 2,611
StDev 1,706
N 14
AD 0,684
P-Value 0,058
Probability Plot of %Scrap top
Normal
Topcore
95% Bonferroni Confidence Intervals for StDevs
1
-1
54321
Topcore
%Scrap top
1
-1
6543210
Test Statistic 0,77
P-Value 0,764
Test Statistic 0,06
P-Value 0,812
F-Test
Levene's Test
Test for Equal Variances for %Scrap top
Data
%Scrap top_2%Scrap top_1
6
5
4
3
2
1
0
Individual Value Plot of %Scrap top_1; %Scrap top_2
Data
%Scrap top_2%Scrap top_1
6
5
4
3
2
1
0
Boxplot of %Scrap top_1; %Scrap top_2

26. x
One-way ANOVA: %Scrap top_1; %Scrap top_2
Source DF SS MS F P
Factor 1 0,26 0,26 0,08 0,779
Error 12 37,57 3,13
Total 13 37,83
S = 1,769 R-Sq = 0,68% R-Sq(adj) = 0,00%
Individual 95% CIs For Mean Based on
Pooled StDev
Level N Mean StDev -------+---------+---------+---------+--
%Scrap top_1 7 2,747 1,653 (-----------------*------------------)
%Scrap top_2 7 2,476 1,878 (-----------------*-----------------)
-------+---------+---------+---------+--
1,60 2,40 3,20 4,00
Pooled StDev = 1,769
Hypothesis Test. One Way Anova.
Top Core Design Vs %Scrap
Conclusion: Accept Ho, Discard Ha.

27. x
Levels
Response
Variables
Constants Noise Variables
Equipments and
measurement
instruments
Experimental
Unit
DOE Type
30 & 45
3,5 & 4,0
Factorial
Experiment
2x2x2x2 = 24
16 pouring. 4
repetitions
Die Coating
Ladel coating
Ceramic inserts in
good conditions
Water Cooling Time in
Center Core (seg)
Factors
3.
Piston 3,9L Part
Number 81124Cycle Time = 83
seg.
Chemicla Analysis
(same furnace)
Water cooling
connections
Visual Inspection.
Visual Aid FAC-003-
001 Rev. 4Pouring speed (seg)
4.
DOE
Same foundry cell
Degassing (ID =
1,5 máx.)
1. Metal Temperature (°C)
2. Water Cooling Temp. (°C)
2% Scrap max.
18 & 30
770 y 790

28. x
Interactions
(A) Center Core water
Cooling Time (°C)
(B) Pouring
Speed (seg)
(C) Water Cooling
Temperature (°C)
(D) Metal
Temperature
(°C)
(1) 30 3.5 18 770
a 45 3.5 18 770
b 30 4.0 18 770
ab 45 4.0 18 770
c 30 3.5 30 770
ac 45 3.5 30 770
bc 30 4.0 30 770
abc 45 4.0 30 770
d 30 3.5 18 790
ad 45 3.5 18 790
bd 30 4.0 18 790
abd 45 4.0 18 790
cd 30 3.5 30 790
acd 45 3.5 30 790
bcd 30 4.0 30 790
abcd 45 4.0 30 790
DOE
Same DOE for both series:
65 – 68 Choke Section &
77 – 80 Permanent Filter

29. x
Trials Results &
Savings
Víctor Espejo

30. x
Cell #: 4 Station #: 8 Machining Line #: 1
Shift: Mach. Date:
Die Cavity Qty m/ced No. Scrap %Scrap
Die Cavity
Pairing
Total Qty
m/ced
Total No
Scrap
Total Pair
% Scrap
3 Blow Holes
1 Oxide Inc.
1 Shrinkage
9 Blow Holes
2 Oxide Inc.
0 Shrinkage
7 Blow Holes
2 Oxide Inc.
0 Shrinkage
10 Blow Holes
0 Oxide Inc.
0 Shrinkage
Total Trial 5104 35 0.69%
870
9
10
0.95%
1.15%
FM Puebla Foundry
3,9L Piston 81124 Scrap Results
Basket #:
"Casting Trials" Choke Section. New Downsprue:
dd/mm/yy
Cav 67 0.80%1129
16
67 & 68 1999 19
11 0.74%
Cav 68
Scrap Defects
0.52%
Cav 65 1615 5 0.31%
65 & 66 3105
Cav 66 1490
In-Gate trials Results. Current Process Conditions

31. x
In-Gate trials Results. Current Process Conditions
Cell #: 4 Station #: 8 Machining Line #: 1
Shift: Mach. Date:
Die Cavity Qty m/ced No. Scrap %Scrap
Die Cavity
Pairing
Total Qty
m/ced
Total No
Scrap
Total Pair
% Scrap
7 Blow Holes
0 Oxide Inc.
0 Shrinkage
8 Blow Holes
0 Oxide Inc.
1 Shrinkage
7 Blow Holes
1 Oxide Inc.
0 Shrinkage
16 Blow Holes
0 Oxide Inc.
0 Shrinkage
Total Trial 5574 40 0.72%
1937
8
16
0.76%
0.83%
FM Puebla Foundry
3,9L Piston 81124 Scrap Results
Basket #:
"Casting Trials" Permanent Filter Ingate:
dd/mm/yy
Cav 79 0.66%1215
16
63A & 64A 3152 24
9 0.75%
Cav 80
Scrap Defects
0.66%
Cav 77 1214 7 0.58%
61A & 62A 2422
Cav 78 1208

32. x
September October November December January February March April May June July August September Octubre
140087 150165 147450 172582 184578 70171 127678 143730
9806 10512 10322 12081 12920 4912 8937 10061
$16,082 $17,239 $16,927 $19,812 $18,605 $7,073 $12,870 $14,488
6404 4457 7076 5379 5804 1932 1912 4108
$10,503 $7,309 $11,605 $8,822 $8,358 $2,782 $2,753 $5,916
$5,579 $9,929 $5,323 $10,991 $10,248 $4,291 $10,117 $8,572
$65,050
* % Scrap average (7%)
Scrap parts after improvement
Scrap Cost = 1.64 USD / piece
SAVINGS TABLE
SIX SIGMA - FOUNDRY MATERIAL SCRAP REDUCTION. PISTON 3.9L
Accumulated Total Savings (USD)
Scrap costs after improvement (USD)
Totales Savings (USD)
Period 2006 - 2007
Machined Parts
*Scrap pieces before improvement (7%)
Scrap costs before improvement (USD)
Material Scrap 81124 (3,9L) After Machining, 2006 - 2007
5.4
1.7
2.3
0.4
1.2
2.7
5.3
5.9
2.1
5.4
8.0
7.1
8.3
6.7
6.2
5.6
8.2
10.710.6
9.7
14.0
14.3
11.3
10.5
7.3
9.8
8.3
2.7
3.23.0
3.3
2.72.6
3.53.5
4.5
4.84.74.6
3.2
2.5
3.63.5
2.4
2.0
4.5
3.8
3.2
2.5
2.12.2
1.5
1.0
1.51.5
2.82.72.92.7
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16-Ago-05
26-Ago-05
05-Sep-05
15-Sep-05
25-Sep-05
05-Oct-05
15-Oct-05
25-Oct-05
04-Nov-05
14-Nov-05
24-Nov-05
04-Dic-05
14-Dic-05
24-Dic-05
03-Ene-06
13-Ene-06
23-Ene-06
02-Feb-06
12-Feb-06
22-Feb-06
04-Mar-06
14-Mar-06
24-Mar-06
03-Abr-06
13-Abr-06
23-Abr-06
03-May-06
13-May-06
23-May-06
02-Jun-06
12-Jun-06
22-Jun-06
02-Jul-06
12-Jul-06
22-Jul-06
01-Ago-06
11-Ago-06
21-Ago-06
31-Ago-06
10-Sep-06
20-Sep-06
30-Sep-06
10-Oct-06
20-Oct-06
30-Oct-06
09-Nov-06
19-Nov-06
29-Nov-06
09-Dic-06
19-Dic-06
29-Dic-06
08-Ene-07
18-Ene-07
28-Ene-07
07-Feb-07
17-Feb-07
27-Feb-07
09-Mar-07
19-Mar-07
29-Mar-07
08-Abr-07
18-Abr-07
28-Abr-07
08-May-07
18-May-07
28-May-07
07-Jun-07
17-Jun-07
27-Jun-07
07-Jul-07
17-Jul-07
27-Jul-07
06-Ago-07
16-Ago-07
26-Ago-07
05-Sep-07
15-Sep-07
25-Sep-07
05-Oct-07
15-Oct-07
25-Oct-07
04-Nov-07
14-Nov-07
24-Nov-07
04-Dic-07
14-Dic-07
24-Dic-07
03-Ene-08
Week
%Scrap
Choke section
improvement in the
current ingate desing
New ingate design, choke
section & permanent filter
firts trials (only 2 series)
New ingate design, choke
section & permanent filter out
of service (maintenance)
New ingate design, choke
section & permanent filter
second trials
Final test & decided to
modify all the ingates with
the choke section
Dacmac quotation on
track, anvilloy insert and
final modification.
Planned time one serie
per month.
Goal = 2.0%

33. x
Capability Study
Automatic Sigma Calculator
Attribute Data
Total Defects 2768
# of opportunities 3
Total units 26255
These are your defects
(dpmo) 35143
These are the DPU 0,1054 232,6
Zbench 3,3101 This is the value of sigma in your process
Entitlement (defects) 18
Color code Not capable
Borderline
Capable
Automatic Sigma Calculator
Attribute Data
Total Defects 4457
# of opportunities 3
Total units 150165
These are your defects
(dpmo) 9893.6
These are the DPU 0.0297 232.6
Zbench 3.8304 This is the value of sigma in your process
Entitlement (defects) 104
Color code Not capable
Borderline
Capable
Z Original Z Improved

34. x
Conclusions:
-The new in-gates design (both choke section and
permanent filter), reduce and stabilize the scrap trend by air
bubbles.
-The additional benefit is the misruns reduction due to high
pouring speed.
Project Status:
-4 set of dies are already modified (total 7 dies set)
-Process control should be improved, die coating, pouring
conditions and ladle cleaning (oxide problems increase).

35. x
Defect Characterization
& Magma Simulation
Mel Jones

36. x
Current In-Gate System.
Proposal In-Gate System.

37. x
PERMANENT FILTER IN-GATE TRIALS
Background
• New in-gate design needed to reduce turbulence during die filling
• More quiescent fill of the die leads to less fine oxide generation during piston casting and should
give better low temperature fatigue properties for the piston alloy – particularly important for
gasoline pistons
New in-gate design now in production at FM Nürnberg

38. x
Filter pins on both sides of the block to help stripping of casting
Permanent filter is designed for global standard twin cavity gasoline piston die

39. x
11Data classification: Internal mm/dd/yyyyFunction / BU name
Permanent filter
Verlauf KP - 9044
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
Jan Feb Mrz Apr Mai Jun Jul Aug
Monat
Auschußin%
0

40. x
CONTROL PLAN
PUEBLA PISTONS
Apr. del CliProducción (Si es necesario):
Prototipo Pre-Lanzamiento Producción Contacto/Telefono Fecha (Orig.) Fecha (Rev.) No. de Revisión
Plan de Control Número: WBGM-FD01 26-Abr-06 4
Número de Parte Nivel de Ingeniería Nombre de la Parte/Descripcion Miembros del Equipo:
No.
Size Frec.
FD50 Start up cell Foundry cell Cell conditions
See
FFD-02
Visual 1 Daily
Quality and Production
check list
FFD-02
Set up parameters.
DPS-6
Foundry cell
Pouring height (ladle
adjustment)
1.0 a 2.0 cm
from the pouring
bush
Rule 1
Every ladle
change
Maintenance check list
Stop production and fix
the height
Foundry cell Ladle alignment
Straight respect
to pouring bush
squadron guide 1
Every ladle
change
Maintenance check list
Stop production and
align the ladles
FD60 Pouring Casting station Metal temperature 780°C ± 10°C
Handle pyrometer /
Control panel
PI-D-FD-xx
1 Every 2 hrs
FFD-01
Production
Stop cell and fix
parameters, separate
product
Robot Motoman Pouring speed 4.0 sec. Max. Cronometer 1
Daily or every
cell start up
Quality and Production
check list
FFD-02
Robot program
adjustment
Casting cell Water cooling system 20 - 29 °C Temperature sensor 1 Every 4 hrs
Production check list
FFD-02
Stop cell and fix
parameters
Water flow Visual 1
Daily or every
cell start up
Quality and Production
check list
FFD-02
Stop cell and fix
parameters
Characteristic
EqupmentProcess decription
Part
number /
Operation
Spec.
Special
Charact.
ProcessProduct
Reaction Plan
Control method
Sample
Evaluation tchnique
or method
Method
14-Jul-02ERIC MIRANDA (01)(222) 404-3100
PC81030C, PC81064G (AFA06072),
PC81063C (AFA06122), PC81124C (AHS29361),
PC81094C (AHS13044)
B2/R005
R005 / R001
R003
PISTÓN FUNDIDO 5.3L & 5.3L FLOTANTE
PISTÓN FUNDIDO 3.5L, PISTÓN FUNDIDO 3.9L
PISTÓN FUNDIDO 4.8L
A. TORIJA, O RODRIGUEZ, V ESPEJO,
S LOPEZ, M HERNANADEZ

41. x
Measurement System Validation (X’s)
X´s (Variables) Controlled by Validation Restreability Location
PI-D-FD-22 Cell 1
PI-D-FD-23 Cell 2
PI-D-FD-24 Cell 3
PI-D-FD-29 Cell 4
Handle Pyrometer Calibration PI-D-FD-07
Control Panel Pyrometer Calibration PI-D-FD-XX 12 Control Panels
Water Cooling Time Casting Stations Timers 8 Casting Stations
Water Cooling Temperature
Fix Thermocouple and
Pyrometer
Calibration
Metal Temperature