6西格玛.pdf

6西格玛.pdfSix Sigma Overview
@
Shanghai Lambda
Schedule
¾ What is Sixsigma
¾ Why Sixsigma
¾ Process and Variation
¾ Sixsigma Roadmap
WhatWhat isis SixSix SigmaSigma
What is Six Sigma
σ: greek letter for standard deviation
B
A C
thethe widerwider thethe spread,spread, thethe biggerbigger thethe variationvariation
What is Six Sigma
Every Human Activity Has Variability...
Target
X
X
XXX
X XX1XσX
defects XXXXXXX X defects
XXXXXXXXXX
X XXXXXXXXXXXXXX
Customer
Specification
ReducingReducing VariabilityVariability IsIs TheThe EssenceEssence ofof SixSix SigmaSigma
What is Six Sigma
Defect and Opportunity
Defect Any event that does not meet a customer
specification.
For example: to process a purchasing order,
defect could be : wrong quantity, wrong item,
wrong price, too long time…
Defect A measurable chance for a defect to occur
Opportunity For example, in one purchasing order
Quantity, item, price, delivery date, vendor,
payment term,processing time
What is Six Sigma
Normal distribution and probability
% %
% %
% % % %
–3S –2S –1S Mean+1S +2S +3S
%
%
%
What is Six Sigma
Normal distribution and sigma level
LSL Target USL
6σ 6σ
σσσσσσσσσσσσ
6σ Process=
Note: + shift
What is Six Sigma
„ A methodology to identify Process
DPMO
measure ,analyze and improve Sigma
business processes to meet
customer requirement with 308,537 2
reduced cost
66,807 3
„ A measure of process capability 6,210 4
to meet customer specification.
A six sigma process only result 233 5
in defects-per-million- 6
opportunity
Defects per Process
Million Capability
„ A strategy to run business in Opportunities
panies (distribution shifted ± s)
What is Six Sigma
Six Sigma - Practical Meaning
99% Good ( Sigma) % Good (6 Sigma)
20,000 lost articles of mail per hour Seven articles lost per