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Introduction to Statistical Quality Control, 4th Edition Introduction to Statistical Quality Control, 4 th Edition Douglas C. Montgomery Arizona State University

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  • Introduction to Statistical Quality Control,

    4th Edition

    Introduction to Statistical

    Quality Control, 4th Edition

    Douglas C. Montgomery

    Arizona State University

  • Introduction to Statistical Quality Control,

    4th Edition

    Chapter 1

    Quality Improvement in the

    Modern Business Environment

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1. The Meaning of Quality and

    Quality Improvement

    1-1.1 Dimensions of Quality

    1-1.2 Quality Engineering Technology

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.1 Dimensions of Quality

    • Performance

    • Reliability

    • Durability

    • Serviceability

    • Aesthetics

    • Features

    • Perceived Quality

    • Conformance to

    standards

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.1 Dimensions of Quality

    • Definitions of Quality

    Quality means fitness for use

    - quality of design

    - quality of conformance

    Quality is inversely proportional to

    variability.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.1 Dimensions of Quality

    • Quality Improvement

    Quality improvement is the reduction of

    variability in processes and products.

    Alternatively, quality improvement is also

    seen as “waste reduction”.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.1 Dimensions of Quality –

    Transmission Example

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.2 Quality Engineering

    Terminology

    Quality Characteristics

    • Physical - length, weight, voltage, viscosity

    • Sensory - taste, appearance, color

    • Time Orientation - reliability, durability,

    serviceability

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.2 Quality Engineering

    Terminology

    Quality engineering is the set of operational,

    managerial, and engineering activities that a

    company uses to ensure that the quality

    characteristics of a product are at the

    nominal or required levels.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.2 Quality Engineering

    Terminology

    Two types of data

    • Attributes Data - discrete data, often in the

    form of counts.

    • Variables Data - continuous measurements

    such as length, weight.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.2 Quality Engineering

    Terminology

    Specifications

    Quality characteristics being measured are

    often compared to standards or

    specifications.

    • Nominal or target value

    • Upper Specification Limit (USL)

    • Lower Specification Limit (LSL)

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.2 Quality Engineering

    Terminology

    • When a component or product does not meet specifications, they are considered to be nonconforming.

    • A nonconforming product is considered defective if it has one or more defects.

    • Defects are nonconformities that may seriously affect the safe or effective use of the product.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-1.2 Quality Engineering

    Terminology

    • Concurrent Engineering

    Team approach to design. Specialists from

    manufacturing, quality engineering,

    management, etc. work together for product

    or process improvement.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-2. A Brief History of Quality

    Control and Improvement

    (Refer to Table 1-1)

    • Walter Shewhart (1924) introduced statistical control chart concepts.

    • The American Society for Quality Control formed in 1946 (now known as the American Society for Quality (ASQ)).

    • 1950s and 1960s saw an increase in reliability engineering, experimental design, and statistical quality control

  • Introduction to Statistical Quality Control,

    4th Edition

    1-2. A Brief History of Quality

    Control and Improvement

    (Refer to Table 1-1)

    • Competition from foreign industries (Japan)

    increases during the 1970s and 1980s.

    • Statistical methods for quality improvement use

    increases in the United States during the 1980s

    • Total Quality Management (TQM) emerges

    during 1970s and into the 1980s as an important

    management tool to implement statistical methods.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-2. A Brief History of Quality

    Control and Improvement

    • Malcolm Baldridge National Quality Award is

    established in 1988.

    • ISO 9000 certification activities increase in U.S.

    industry in the 1990s.

    • Motorola’s Six-Sigma initiative begins in the

    1990s.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-3. Statistical Methods for

    Quality Control and Improvement

    Three major areas:

    • Statistical process control (SPC)

    • Design of experiments (DOX)

    • Acceptance sampling

  • Introduction to Statistical Quality Control,

    4th Edition

    1-3. Statistical Methods for

    Quality Control and Improvement

    Statistical ProcessControl (SPC)

    • Control charts are

    used for process

    monitoring and

    variability reduction.

    • SPC is an on-line

    quality control tool.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-3. Statistical Methods for

    Quality Control and Improvement

    Design of Experiments

    • Experimental design is an approach to

    systematically varying the controllable input

    factors in the process and determine the effect

    these factors have on the output responses.

    • Experimental designs are off-line quality tools.

    • Crucial for variability reduction.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-3. Statistical Methods for

    Quality Control and Improvement

    Acceptance Sampling

    • Acceptance sampling is the inspection and classification of a sample of the product selected at random from a larger batch or lot and the ultimate decision about disposition of the lot.

    • Two types:

    1. Outgoing inspection - follows production

    2. Incoming inspection - before use in production

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4. Other Aspects of Quality

    Control and Improvement

    Total Quality Management (TQM)

    • TQM is a managerial framework to accomplish quality improvement.

    • Other names and related approaches:

    – Company-Wide Quality Control (CWQC)

    – Total Quality Assurance (TQA)

    – Six-Sigma

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4. Other Aspects of Quality

    Control and Improvement

    1-4.1 Quality Philosophy and Management

    Strategies

    1-4.2 The Link Between Quality and

    Productivity

    1-4.3 Quality Costs

    1-4.4 Legal Aspects of Quality

    1-4.5 Implementing Quality Improvement

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4.1 Quality Philosophy and

    Management Strategies

    Three Important Leaders

    • W. Edwards Deming

    - Emphasis on statistical methods in quality improvement (see Deming’s 14 points)

    • Joseph Juran

    - Emphasis on managerial role in quality implementation

    • Armand V. Feigenbaum

    - Emphasis on organizational structure

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4.1 Quality Philosophy and

    Management Strategies

    • Total Quality Management (TQM)

    • Quality Standards and Registration

    – ISO 9000

    • Six Sigma

    • Just-In-Time, Lean Manufacturing,

    Poka-Yoke, etc.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4.2 The Link Between Quality

    and Productivity

    • Effective quality improvement can be

    instrumental in increasing productivity and

    reducing cost.

    • The cost of achieving quality improvements

    and increased productivity is often

    negligible.

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4.3 Quality Costs

    Quality Costs are those categories of costs that are

    associated with producing, identifying, avoiding,

    or repairing products that do not meet

    requirements. These costs are:

    • Prevention Costs

    • Appraisal Costs

    • Internal Failure Costs

    • External Failure Costs

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4.4 Legal Aspects of Quality

    The re-emergence of quality assurance as

    an important business strategy is in

    part a result of

    1. Consumerism

    2. Product Liability

  • Introduction to Statistical Quality Control,

    4th Edition

    1-4.5 Implementing Quality

    Improvement

    • Strategic Management of Quality

    • Almost all successful efforts have been

    management-driven.

    • Too much emphasis on registration and

    certification programs (ISO, QS)

    – Insufficient focus on quality planning and design,

    quality improvement, overemphasis on quality

    assurance

    – Poor use of available resources