Six Sigma Overview

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Six Sigma Overview
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The Classical View of Performance

• Six-Sigma is a philosophy
• Why isnt 99 acceptable good enough...??
• 20,000 lost articles of mail every hour.
• 15 minutes each day of unsafe drinking water.
• 5,000 incorrect surgical procedures per week.
• 4 or more accidents per day at major airports.
• 200,000 wrong drug prescriptions each year.
• 7 hours each month without electricity.

4 Sigma Process Capability 99.38
Current Standard
6 Sigma Process Capability 99.99966
World-Class
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History of 6 Sigma

• 6 Sigma manufacturing philosophy came from
  Motorola
• They recognised that sufficient process
  improvement would not occur using a conventional
  approach to quality. It was developed to help
  them reduce variation within a process by
  focusing effort on improving inputs to a process
  rather than reacting to outputs.
• The process was failing the customer expectations
• Traditionally, processes aimed for process
  capability of 3 to 4 sigma (Cpk1.0 to 1.33 or
  93 to 99.3 acceptable)
• The customer received 6200 defective product per
  million at best
• Processes now aim for 6 sigma (Cpk2)
• The customer would receive 3.4 defective product
  per million

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6 sigma Process Capability What is it (CPK)

• 3 Sigma ( Process capability of 1 CPK )
• if the process (lorry) slightly varies then the
  scrap or damage will occur
• 6 Sigma ( Process capability of 2 CPK )
• if the process (lorry) varies, there will be no
  scrap or damage

Curbs required process tolerances
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Understanding Variability

• Variation exists in everything. Even the best
  machine cannot make every unit exactly the same.
• Improved capability, becomes a necessity, due to
  the need of
• improved designs
• lower costs
• better performance
• All of this leads to the need of tighter
  tolerances
• This means that the ability to operate to a tight
  tolerance, without producing defects becomes a
  major advantage

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Improvement methodology
KPIV Key Process Input Variables
Controllable Inputs
X1
X2
X3
Quality Characteristics Outputs
Inputs Raw materials, components, etc.
The Process
Y1, Y2, etc.
N1
N2
N3
Uncontrollable Inputs
On target, minimum process variation
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Improvement methodology
D M A I C
Define
Measure
Analyze
Improve
Control
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Improvement methodology
Define

• Define terms of reference (Charter the project)
• Team / customer / project charter
• Brain storming
• Mind maps
• Affinity diagrams
• High level Process Maps
• Systematic diagrams / Fault tree
• Business Process Mapping
• Define customer requirements (Voice of the
  customer)
• QFD Quality Function Deployment

• To develop a team charter.
• To define the customers and their requirements
  (CTQ Critical to Quality).
• To map the business process to be improved

Characteristics
Product / customers
Importance out of 10
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Define

• Define terms of reference (charting a project)
• What you can deliver to the customer and the
  support you need from the customer to facilitate
  a successful improvement (contract of engagement)
• Brain storming, Mind maps, Affinity diagrams,
  High level Process Maps, Systematic diagrams /
  Fault tree, Business Process Mapping
• Tools to explore a problem, project or current
  thinking.
• Tools to group those ideas logically.
• Then define a route map to improvement, the risk
  involved and how to mitigate that risk.
• Define customer requirements (Voice of the
  customer)
• QFD Quality Function Deployment, is a method of
  defining what the customer needs, what is
  critical to there business success prioritise
  objectives to meet the customer need.

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Improvement methodology

• Voice of the process
• Data Collection - 7 quality tools
• Tally charts
• Bar charts
• Pareto
• Run charts
• Control charts
• Cause effect
• Check sheets
• Evaluate measurement systems
• Gauge RR
• Select measures of performance
• Quality Function Deployment

Measure

• To measure and understand baseline performance
  for the current process

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Measure

• Voice of the process (7 quality tools)
• Tally charts, Bar charts, Pareto, Run charts,
  Control charts, Cause effect, Check sheets.
• Evaluate measurement systems Gauge RR
• Every process has variation and measurement
  system, tools cmm are no exception.
• Typical your measurement process needs to be
  ACCURATE, REPEATABLE REPRODUCIBLE to less than
  10 of the tolerance you are trying to measure to
  proven to be so.
• Select measures of performance
• QFD Quality Function Deployment is a method of
  defining what the customer needs and what is
  critical to there business success and
  prioritising performance measures to support the
  customers need.

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Improvement methodology

• Investigate source of variation
• (Special cause / Common causes)
• Stratification of data to get information
• Cause effect
• CP CPK
• Fault tree
• Contingence analysis
• FMEA (Failure Mode Effect Analysis)
• Design of experiments (DOE)
• Detailed process maps

Analyze
Seek to- Prioritise Understand Clues Causes
Monitor improvements Look for signals
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FMEA (failure mode effect analysis)
Why Battles are Lost
Lost Shoe
Lost Nail
Lost Horse
Lost Soldier
Lost Battle

• FMEA
• Identifies the ways in which a product or process
  can fail
• Estimates the risk of specific causes with regard
  to these failures
• Prioritizes the actions that should be taken to
  reduce the chance of failure

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DOE - (design of experiments)will help us
identify...

• factors which shift the average
• factors which affect variation
• factors which shift the average and affect
  variation
• factors which have no effect

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DOE - (design of experiments) Measure the Process
Establish the performance baseline
Controllable Inputs
X1
X2
X3
Quality Characteristics Outputs
Inputs Raw Materials, components, etc.
The Process
Y1, Y2, etc.
N1
N2
N3
Uncontrollable Inputs
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DOE - (design of experiments) Analyse the Process
Controllable Inputs
Quality Characteristics Outputs
The Process
Inputs Raw Materials, components, etc.
Y1, Y2, etc.
Uncontrollable Inputs
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DOE - (design of experiments) Improve the Process
Controllable Inputs
X
Quality Characteristics Outputs
X
Inputs Raw Materials, components, etc.
The Process
Y1, Y2, etc.
X
Uncontrollable Inputs
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DOE - (design of experiments) Control the Process
Error Proofing
Quality Characteristics Outputs
LSL
USL
Inputs Raw Materials, components, etc.
Y1, Y2, etc.
The Process
Work Instructions 5 Cs
Check Lists
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Analyze

• Investigate source of variation (Special cause /
  Common causes)
• Special cause variation are the one off,
  occasional and obvious cause of a process /
  quality problems.
• Common cause variation are the day in day out
  causes of process problems, because the process
  is not stable enough, they are hidden (these form
  80 of process problems)
• Conventional non-conformance management systems
  seek to solve special cause variation (e.g.
  concessions) - but these only represent 15 - 20
  of the total variation.
• 6 Sigma addresses all variation.

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Improvement methodology

• Prioritise improvements
• Impact Vs Effort
• Brainstorming
• Affinity diagrams
• Solution selection matrix
• Tactical implementation plans
• Deliver improvements (reduce variation
  systematically)

Improve
Customer protection Get control Improve process
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Improve

• Prioritise improvements
• Tool commonly in uses are, Impact Vs Effort,
  Brainstorming, Affinity diagrams, Solution
  selection matrix.
• These tools help define the best method to meet
  the customer need (as defined in the QFD)
• Tactical implementation plans
• Deliver improvements to reduce variation
  systematically i.e. make a change, note the
  improvement and make the next improvement.
• Critical we need to establish that any change is
  a change for the good.

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Improvement methodology

• Control the process
• Recover
• Control plans
• Escalation process
• Prevent
• Poke yoke (mistake/ error proof)
• Monitor
• Control charts
• Checksheets
• Documentation and Standardisation

Control
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Control

• Control the process
• Recover, Control plans, Escalation process.
• Prevent by Poke yoke (fool proof the process) to
  fundamentally remove the rood causes of process
  variation.
• Monitor, Control charts, Checksheets,
  Documentation and Standardisation, to ensure that
  stable process is maintained and that the process
  does not degrade.
• The objective is to remove the root causes of
  process variation, management are only left with
  a few critical input variables in the process
  that need controlling and not all inputs as
  before.

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Where does 6 Sigma fit with Lean

• Lean and 6 Sigma both seek to deliver business
  improvement
• They are different in the methods used and tools
  employed
• Lean typically address the total manufacturing
  environment
• 6 sigma typical address the root cause of process
  variation
• There is significant benefit from using the most
  appropriate tools and improvement methodology to
  meet the customer requirements

6 Sigma improvements
Lean improvements