Tutorial 1: intro
LEAN PRINCIPLES
,DEADLY WASTES (TIMWOODS)
HISTORY
1978 At a Motorola officer’s meeting Art Sundry, Motorola VP, stood up and stated that
Motorola’s quality stunk.
1981 Motorola’s chairman, Bob Galvin, decided that after meeting with customers and studying
Motorola’s quality effort that the company would now be focused on reducing manufacturing
defects by 10 fold within a 5 year period.
1987 Motorola met its goal of a 10 fold reduction in defects. Unfortunately, some major
competitors had improved faster in that time period. The goal of 10 fold improvement was a good
goal but 5 years was not fast enough.
1987 Motorola top management raised the “bar” to a 10 fold improvement every 2 years, and a
target of 3.4 defects per million was set for 5 years. The name Six Sigma was given to this target.
SIX SIGMA PRINCIPLES
Statistical concept that represents the amount of variation present in a process relative to customer
requirements or specifications
Business philosophy of focussing on continuous improvement by understanding customers’needs,
analyzing business processes, and instituting proper measurement methods
FLOUR MILL EXERCISE
,A flour mill produces bags of flour with a target weight of 50 kg
Customers allow for a tolerance of 1% = 0.5 kg, so weights in between 49.5 kg and 50.5 kg are within
customer specifications
A sample of n=10 bags showed the following weights:
49.3 50.1 50.6 49.9 50.0
49.6 49.8 50.7 50.1 49.9
How capable is the bag filling process?
Obs. (i ¿ Value ( x i) x i−x́ 2
( x i−x́ )
1 49.3 -0.7 0.49
2 50.1 0.1 0.01
3 50.6 0.6 0.36
4 49.9 -0.1 0.01
5 50.0 0.0 0.00
6 49.6 -0.4 0.16
7 49.8 -0.2 0.04
8 50.7 0.7 0.49
9 50.1 0.1 0.01
10 49.9 -0.1 0.01
P. 1-26 OF THE JOGGER
, Tutorial 2: Lean
IDEAL LEAN SYSTEM LAY- OUT
Line flow
A single product flows from workstation to workstation
All workstations use same amount of time
Lead time = processing time
LEAN BUILDING BLOCKS – CREATE FLOW
Pull trigger of flow – pull and Kanban
Ensure quality in flow – 5S, error proofing, total productive maintenance, visual controls
KAIZEN
Kai means change
Zen means good (for the better)
Gradual continuous improvement
Involving everyone
Kaizen event/blitz
Total focus on a defined process to create radical improvement in a short period of time
Typically five days (one week) long
VALUE STREAM MAPPING
“Follow a product’s production path from customer to supplier, and carefully draw a visual
representation of every process in the material and information flow.” (Learning to see, Rother and
Shook)
LEAN PRINCIPLES
,DEADLY WASTES (TIMWOODS)
HISTORY
1978 At a Motorola officer’s meeting Art Sundry, Motorola VP, stood up and stated that
Motorola’s quality stunk.
1981 Motorola’s chairman, Bob Galvin, decided that after meeting with customers and studying
Motorola’s quality effort that the company would now be focused on reducing manufacturing
defects by 10 fold within a 5 year period.
1987 Motorola met its goal of a 10 fold reduction in defects. Unfortunately, some major
competitors had improved faster in that time period. The goal of 10 fold improvement was a good
goal but 5 years was not fast enough.
1987 Motorola top management raised the “bar” to a 10 fold improvement every 2 years, and a
target of 3.4 defects per million was set for 5 years. The name Six Sigma was given to this target.
SIX SIGMA PRINCIPLES
Statistical concept that represents the amount of variation present in a process relative to customer
requirements or specifications
Business philosophy of focussing on continuous improvement by understanding customers’needs,
analyzing business processes, and instituting proper measurement methods
FLOUR MILL EXERCISE
,A flour mill produces bags of flour with a target weight of 50 kg
Customers allow for a tolerance of 1% = 0.5 kg, so weights in between 49.5 kg and 50.5 kg are within
customer specifications
A sample of n=10 bags showed the following weights:
49.3 50.1 50.6 49.9 50.0
49.6 49.8 50.7 50.1 49.9
How capable is the bag filling process?
Obs. (i ¿ Value ( x i) x i−x́ 2
( x i−x́ )
1 49.3 -0.7 0.49
2 50.1 0.1 0.01
3 50.6 0.6 0.36
4 49.9 -0.1 0.01
5 50.0 0.0 0.00
6 49.6 -0.4 0.16
7 49.8 -0.2 0.04
8 50.7 0.7 0.49
9 50.1 0.1 0.01
10 49.9 -0.1 0.01
P. 1-26 OF THE JOGGER
, Tutorial 2: Lean
IDEAL LEAN SYSTEM LAY- OUT
Line flow
A single product flows from workstation to workstation
All workstations use same amount of time
Lead time = processing time
LEAN BUILDING BLOCKS – CREATE FLOW
Pull trigger of flow – pull and Kanban
Ensure quality in flow – 5S, error proofing, total productive maintenance, visual controls
KAIZEN
Kai means change
Zen means good (for the better)
Gradual continuous improvement
Involving everyone
Kaizen event/blitz
Total focus on a defined process to create radical improvement in a short period of time
Typically five days (one week) long
VALUE STREAM MAPPING
“Follow a product’s production path from customer to supplier, and carefully draw a visual
representation of every process in the material and information flow.” (Learning to see, Rother and
Shook)
