Quality - M2

• Quality


  • Judgments by an individual, organization or other entity
  • Fitness for purpose
  • The ability of a product to satisfy the users
  • Acceptable performance
  • The product meets its requirements (a systems engineer's perspective)
  • Whatever the customer says it is (An American restaurant perspective)
• Perception of Quality


  • Some people will pay a premium for high-end brands, based on their own criteria (Individual Quality Experience)
• Factors that producers and customers consider for quality

  • Innate excellence
  • Fitness for intended use
  • Performance, reliability and/or durability
  • Level of technology
  • Convenience of use
  • Attractive appearance and style
  • Value, or the ratio of performance to cost
  • Customer service before and during sales
  • On-time deliveries
  • After-sales service
• Quality Doctrine


  • Quality is the responsibility of everyone involved
  • Quality requires continuous improvement in all areas
  • Quality comes from prevention at the earliest possible stage in the system
  • Prioritise improvements for maximum system benefit
• Statistical Process Control


  The key parameters of a process are measured & monitored to evaluate the process in terms of capability and trend
• Six-Sigma


  A quality methodology that brings together statistical process control, a focused, customer-oriented culture, organized staff training, and leading management methods
• Six-Sigma (Statistical Perspective)


  • At 6 standard deviations from the mean, there are only 3.4 rejects per million samples
• Six-Sigma Training Levels


  • Black Belt
  • Green Belt
  • Yellow Belt (basic training)
• The Six-Sigma Framework (DMAIC)


  1. Define

  2. Measure

  3. Analyse

  4. Improve

  5. Control
• SMART Problem Statements


  • Specific
  • Measurable
  • Achievable
  • Relevant
  • Timely
• Six-Sigma Team


  • Six Sigma Champion
  • Project Sponsor
  • Project Leader (Black Belt)
  • Team Members (Green Belt or process specialists)
• Key Performance Indicators (KPIs)

  Essential parameters that define the process, covering customer perspective, supplier perspective, effectiveness, and efficiency
• KPIs for a Courier Service

  • Speed of delivery
  • Cost of delivery
  • Reliability (lost or damaged parcels)
  • Customer service
  • Location of collection centre
  • Number of parcels
  • Staffing levels
  • Number of delivery vehicles
  • Number of collection centres
  • Average delivery cost target
• Caution should be applied when using parts per million (ppm) as a statistic, as it may not be suitable for all processes
• Analysis Tools


  • Value Stream Mapping
  • Root Cause Analysis
  • FMEA
  • Brainstorming
  • Fishbone diagrams
  • Fault Trees
  • Pareto Analysis
• Design of Experiments (DoE) is a statistically-based method for designing experiments to test the significance of process variables
• Quality Management Tools


  • Value Stream Mapping
  • Root Cause Analysis
  • FMEA
  • Brainstorming
  • Fishbone diagrams
  • Fault Trees
  • Pareto Analysis
• The Analyse Stage


  The Quality Team will come up with ideas and theories as to how the process may be improved. These must be tested somehow to see why we have unacceptable variation in final thickness.
• How do we test the significance of each variable?

  • Change one variable at a time
  • Design of Experiments (DoE) which is a statistically base method for designing experiments
• The Improve Stage


  1. Generate potential solutions

  2. Select the best solutions

  3. Assess the risks

  4. Pilot and Implement
• Solution Screening


  • Will the solutions eliminate the root cause of the problem?
  • Are the solutions likely to be effective?
  • Will the customer accept the solutions?
  • Will business accept the solutions?
  • Can the solutions be standardised?
• Comparison to 'World's Best Practice'

  Comparison could be with another process within their own organisation, other organisations in a similar sector, or organisations in unrelated sectors, but who share the basic problem.
• Why do we need control?

  From a scientific perspective, ordered systems left to their own devices will become disordered. Entropy or the second law of thermodynamics
• The Control Stage


  1. Establish control

  2. Establish a monitoring system

  3. Establish continuous improvement system
• Robust Design


  Quality starts in the design phase. This is where many of the features that are likely to cause failure originate.
• System Design


  The functional level - what makes it work? This includes sub systems, components, materials, and production and process technologies.
• Parameter Design


  The parameters and values which must be incorporated in the design. The product must be robust and reliable, but not over-engineered to the point that the cost will be excessive or the quality will be difficult to manage.
• Tolerance Design


  The engineering design of any part will involve dimensional tolerances. It is important that tolerances should not be either over or under specified.
• Supplier involvement


  Current Lean thinking acknowledges the abilities of the best suppliers and integrates them fully into the design and development stage.
• Poka-Yoke


  A technique developed by Shigeo Shingo to eliminate human error, as far as is possible, by design.
• Examples of Poka-Yoke


  • Parts that can only fit in one place
  • Assemblies in which components can only fit in one orientation
  • Parts delivered in sectored trays so that any parts not used in the assembly are easily seen
  • Kitting
• Zero Defects


  A concept originated by the Martin Marietta company in the 1960s as a response to the requirements of the early space industry.
• Four Principles of Zero Defects

  • The definition of quality is conformance to requirements

  2. Defect Prevention is preferable to Quality Inspection and Correction

  3. The Quality Standard is Zero Defects

  4. Money is the unit of quality
• Zero Defects was different from six-sigma which needs some failure statistics
• All failures represent a cost to the organisation, including inspection time, labour, rework, scrap, lost sales revenue, and cost of loss of customer confidence
• Zero defects was popularised from 1961-1964, but crew rated spacecraft losses continued to occur, including Apollo 1, Soyuz 1, Soyuz 11, Challenger, and Columbia