DESIGN OF A RATING SYSTEM FOR DESIGN OF A RATING SYSTEM FOR SUPPLIERS OF PRINTED WIRING SUPPLIERS OF PRINTED WIRING

BOARDS AT HAMILTON SUNDSTRANDBOARDS AT HAMILTON SUNDSTRAND

By:

Travis Bossidy, IE

And

Patrick Dabrowski, IE

Industrial Advisor: Steve Webster

Faculty Advisor: Dr. Abdul Kamal

IntroductionIntroduction

• Needs to improve the way they rate supplier quality for printed wiring boards (PWB).

• Current system uses PPM• Problem: system only takes into account

number of defective parts• Other aspects of quality have to be

considered

Problem StatementProblem Statement

A supplier quality rating system that rates all aspects of supplier quality in order to monitor and compare suppliers of PWB

Components of Supplier Components of Supplier QualityQuality

PPM

Complexity

Criticality

PAIN

PPMPPM

Number of Parts Per Million defective

(Quantity Defective/Throughput)*106 = PPM

Only takes into account quantity of defective parts

ComplexityComplexity

All PWB differSimpler parts are easier to make according

to specsSuppliers need to be rewarded for making

complex parts

CriticalityCriticality

Defects differ in how they affect the partSome defects are not as serious as others

PAINPAIN

Where in the process the defect is located

Further along in the process, the more value added

Hamilton Sundstrand's “Rule of Ten”

Rating SystemRating System

All four components will be placed into an equation

The value will be in adjusted PPM (PPMNEW)

The PPMNEW can be higher or lower than the original PPM

The EquationThe Equation

The original PPM equation will be used

Each additional component will be represented by a factor

The output of the equation will be PPMNEW

Median values for each component will be needed

Component FactorsComponent Factors

Complexity– Scale of 1-4– 4 being the most complex– Factor determined from sum of 11 different

complexity characteristics– Median value is 2.5, linear relationship– Limits for this scale created by histogram

method using Tyco's complexity data

Component Factors (continued)Component Factors (continued)

Complexity histogram– TYCO had their PWB summed and rated– Hamilton Sundstrand only wanted 11 of the

21 characteristics included.– Sum was recalculated, were redistributed in

the scale attempting to mirror the same percentages

Component Factors (continued)Component Factors (continued)TYCO and Recalculated Factors

0

20

40

60

80

100

120

140

4 3 2 1

COMPLEXITY FACRORS

NU

MB

ER

OF

PA

RT

S

Tyco Factors

HS Factors

TYCO Factors Resumed FactorsFactor Scale Amount % Scale Amount %

4 >41 11 3.36 >23 14 4.283 31 - 40 67 20.49 17 - 22 63 19.262 21 - 30 125 38.24 10. -16 119 36.391 1. - 20 124 37.92 1. - 9 131 40.06

Component Factors (continued)Component Factors (continued)

Criticality– Scale 1-10– 10 being the most critical defect– If there is more than 1 defect, then the highest

value is used– All possible defects were recorded and factor

were given– Median value is 5.5, linear relationship

Component Factors (continued)Component Factors (continued) PAIN

– Each step in the process was assigned a value from 10-1000– 10 being receiving inspection, 1000 being field failure– Steps had to be assigned numeric values

HS-Code Step in Process PAIN Numeric StepCRM Production Return 1000 3TEST FAILUREFinal ATP 100 2TEST FAILUREEss Vibe/Thermal 80 1.8TEST FAILUREPreliminary ATP 60 1.6SHOP Functional Test 40 1.4SHOP Cable Test/Genrad 30 1.3SHOP ASSY 20 1.2RI Rec Inspection 10 1

Component Factors (continued)Component Factors (continued)

PAIN (continued)– Graph was created with numeric steps and Pain– Then an equation was determined using a trend

linePAIN vs. Numeric Steps in the Process

0

200

400

600

800

1000

1200

0 1 2 3 4

Steps in Process

PA

IN

w = 1.155e2.1692 X

Where: w = PAIN associated with step x = Numeric value of step in the process

Component Factors (continued)Component Factors (continued)

w = 1.155e2.1692 X

Where: w = PAIN associated with step x = Numeric value of step in the process

PAIN vs. Numeric Steps in the Process

0

200

400

600

800

1000

1200

0 1 2 3 4

Steps in Process

PA

IN

Component Factors (continued)Component Factors (continued)

PAIN (continued)– Equation had to be normalized

– Divided by a factor of 10

– This put it on a 1-10 scale

– Except for field failure-100

Component Factors (continued)Component Factors (continued)

PAIN (continued)– Median value was found through integrating

curve– From the area under the curve, the median

PAIN and where it occurs in the process was found by locating the 50% point of the area

– Median PAIN was 528 at numeric step number 2.67.

Determining EquationDetermining Equation

D*(.0189 (.155e2.1692 X )*(0.4)y)*(0.182(z))

____________________________________ *106 = PPMNEW

T

Where: D= # of parts found defective

x= factor corresponding with step where defect is found

y= factor corresponding with how complex each board is

z= factor corresponding with how critical each defect is

T=Throughput

Final EquationFinal Equation

D*( .0029e2.1692 X )*( 0.4 y )*( 0.182 z )

___________________________________ *106 = PPMNEW

T

DATA cubeDATA cube

Once equation was finalized , will be put into a data cube

The data cube has all of TYCO’s quality information needed to produce PPMNEW.

The PPMNEW would be compared to PPM to determine overall impression of TYCO to validate equation

Future of ProjectFuture of Project

Once the equation is ran through Data Cube, the equation can be validated

Then it can be applied to all of PWB suppliers

Moving Average will monitor suppliersCorrective Action can be taken

ABET ConcernsABET Concerns

Economic ConcernsEthical ConcernsSocial ConcernsPolitical ConcernsSustainability

Any Questions ?Any Questions ?