Management of Quality: Operations Management Dr. Ron Lembke
Management of Quality: Operations Management Dr. Ron Lembke
Management of Quality: Operations Management Dr. Ron Lembke
Management
Quality … you know what it is, yet you don’t know what it is.
But that’s self-contradictory. But some things are better
than others, that is, they have more quality. But when you
try to say what the quality is, apart from the things that
have it, it all goes poof! There’s nothing to talk about. ...
Robert M. Pirsig, Zen and the Art of Motorcycle
Maintenance, p. 163
WHAT IS QUALIT Y?
Dear IBM:
We don’t know why you
want 1.5% defective parts,
but for your convenience
we have packaged them
separately.
Sincerely,
© 1995 Corel Corp.
W. EDWARDS DEMING
To get certified:
Have a written set of procedures for every activity
Have your employees always follow procedures
Pay someone to come and verify that you always follow
your written procedures
If procedures are followed, your products
should be consistently, uniformly good
BASIC PREMISE
1991 1997
MALCOLM BALDRIGE DOUBLE-WINNER #1:
SOLECTRON
1991 , 1997
TWO GREAT HONORS
Oopsie!
I guess somebody’s
processes aren’t under control
6 (6 SIGMA)
3 sigma: 3
Probability outside range = (1 – 0.99865) * 2 = 0.0027
Defect rate = 2,699 defects per million opportunities
6 sigma: 6
Probability part outside range = 0.00000000198024
Defect rate = 0.00197 dpm
1.97 defects per BILLION
DEFECT RATES - 1
3 6
6 SIGMA
2.5%
2.0%
1.5%
1.0%
0.5%
0.0%
Sediment Hoppy Flat Skunky Misc
Defects
WILFREDO PARETO 1848-1923
Italian Economist
“80/20” rule: 80% of the wealth is
controlled by 20% of the people Cours
d'économie politique (1896-7)
80/20 rule believed to apply much
more widely
20% products are 80% of sales
1906- “Pareto Optimality” – not
possible to make anyone better off (in
his own estimation) without making
someone else worse off
CAUSE & EFFECT DIAGRAM EXAMPLE
Too Many
Defects
CAUSE & EFFECT DIAGRAM EXAMPLE
Method Manpower
Main Cause
Too Many
Defects
Material Machinery
Main Cause
CAUSE & EFFECT DIAGRAM EXAMPLE
Method Manpower
Drill
Tired Too Many
Defects
Wood
Steel Lathe
Material Machinery
CAUSE & EFFECT DIAGRAM EXAMPLE
Method Manpower
Over
Drill Time
Slow Tired Too Many
Defects
Wood Not
maintained
Not dried Steel Lathe
Material Machinery
CONTROL CHART EXAMPLE
X
70
60
50 UCL
40
30
20
10
LCL
0
1 2 3 4 5 6 7 8 9 10 11 12
Time
DILBERT’S VIEW
FORTUNE STORY