Title: ?????? (Statistical Process Control)
1????
- ??????
- ?????? (Statistical Process Control)
- ???? (Process Design)
- ???? (Acceptance Sampling)
2????
3Dimensions of Quality(David Garvin, 1987)1
- Performance
- Will the product do the intended job?
- ??????????
- Durability
- How long does the product last?
- Aesthetics
- What does the product look like?
- Conformance to standards
- Is the product made exactly as the designer
intended?
4Dimensions of Quality(David Garvin, 1987)2
- Features
- What does the product do?
- ??????,????????,??????????
- Serviceability
- How easy is it to repair the product?
- Perceived Quality
- What is the reputation of the company or its
product? - Reliability
- How often does the product fail?
5Definitions of Quality1
- Quality means fitness for use (Quality is
customer satisfaction.) (Joseph M. Juran) - - quality of design
- - quality of conformance
- Quality is inversely proportional to variability.
6Definitions of Quality2
- Quality is conformance to requirements. (Crosby)
- Quality should be aimed at the needs of the
consumer, present and future. (Deming) - Quality is the total composite product and
service characteristics of marketing,
engineering, manufacture, and maintenance through
which the product and service in use will meet
the expectations of the customer. (Feigenbaum)
7Definitions of Quality3
- Quality is the loss (from function variation and
harmful effects) a product causes to society
after being shipped, other than any losses caused
by its intrinsic functions. (Taguchi) - Quality is the totality of features and
characteristics of a product or service that bear
on its ability to satisfy stated or implied
needs. (ISO 9000)
8Definitions of Quality4
9Quality Improvement
- Quality improvement is the reduction of
variability in processes and products. - Alternatively, quality improvement is also seen
as waste reduction.
10Transmission Example
11Quality Engineering Terminology1
- Quality Characteristics (critical-to-quality,CTQ)
- Physical - length, weight, voltage, viscosity
- Sensory - taste, appearance, color
- Time Orientation - reliability, durability,
serviceability
12Quality Engineering Terminology2
- 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.
13Quality Engineering Terminology3
- Two types of data
- Attributes Data - discrete data, often in the
form of counts. - Variables Data - continuous measurements such as
length, weight.
14Quality Engineering Terminology4
- Specifications
- Quality characteristics being measured are
often compared to standards or specifications. - Nominal or target value
- Upper Specification Limit (USL)
- Lower Specification Limit (LSL)
15Quality Engineering Terminology5
- When a component or product does not meet one or
more of its 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.
16Quality Engineering Terminology6
- Concurrent Engineering (vs. over-the-wall)
- Team approach to design. Specialists from
manufacturing, quality engineering, management,
etc. work together for product or process
improvement.
17A Brief History of Quality Control and
Improvement1
- 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
18A Brief History of Quality Control and
Improvement2
- 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.
19A Brief History of Quality Control and
Improvement3
- Malcolm Baldridge National Quality Award is
established in 1988. - ISO 9000 certification activities increase in
U.S. industry in the 1990s. - Motorolas Six-Sigma initiative begins in the
1990s.
20?????
- ????(quality control, QC)
- ????(quality assurance, QA)
- ????(quality management, QM)
21????1
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- ???????????????????????,??????????????????????????
,???????????,?????????????? - Statistical quality control (SQC) refers to the
use of statistical methods of production
monitoring and parts inspection, wherein
statistical data are collected, analyzed, and
interpreted to solve quality problems.
22????2
- ??????(Deming Cycle) (P-D-C-A????)
- Plan(??)
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- Do(??)
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- Check(??)
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- Action(??)
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???????????,????????,?????????????????,???????????
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?????????,???????????????,???????,????????????????
25Statistical Methods for Quality Control and
Improvement
- Three major areas
- Statistical process control (SPC)
- Design of experiments (DOE)
- Acceptance sampling
26Statistical ProcessControl (SPC)
- Control charts are used for process monitoring
and variability reduction. - SPC is an on-line quality control tool.
27Design 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.
28???????????
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- ????(controllable factors)
- ??????????
- ????(noise factors)
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29Acceptance 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
30Quality Philosophy and Management
Strategies
- Three Important Leaders
- W. Edwards Deming
- - Emphasis on statistical methods in quality
improvement (see Demings 14 points) - Joseph M. Juran
- - Emphasis on managerial role in quality
implementation - Armand V. Feigenbaum
- - Emphasis on organizational structure
31W. Edwards Deming
- Taught engineering, physics in the 1920s,
finished PhD in 1928 - Met Walter Shewhart at Western Electric
- Long career in government statistics, USDA,
Bureau of the Census - During WWII, he worked with US defense
contractors, deploying statistical methods - Sent to Japan after WWII to work on the census
32???14?????(Demings 14 points)
- ?????????????????,?????????????
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- ???? vs. ????
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33??
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34Joseph M. Juran
- Born in Romania (1904), immigrated to the US
- Worked at Western Electric, influenced by Walter
Shewhart - Emphasizes a more strategic and planning oriented
approach to quality than does Deming - Juran Institute is still an active organization
promoting the Juran philosophy and quality
improvement practices
35Quality Trilogy (Joseph M. Juran)
- Quality Control
- Evaluate actual product performance
- Compare actual performance to product goals
- Act on the difference
- Quality Improvement
- Establish the infrastructure
- Identify the improvement projects
- Establish project teams
- Provide the teams with resources, training and
motivation to diagnose the causes stimulate
remedies establish controls to hold the gains
- Quality Planning
- Determine who the customers are
- Determine the needs of the customers
- Develop product features that respond to
customers needs - Develop processes able to produce the product
features - Transfer the plans to the operating forces
36Total 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
37Implementation of Total Quality Management
- Management commitment and involvement
- Motivation and change
- Responsibility and authority
- Training and Education
- Communication
- Quality in all aspects of the company
38ISO 90002000
39ISO 90012000
- Scope
- Normative References
- Definitions
- Quality management systems
- Management responsibility
- Resource management
- Product (or Service) realization
- Measurement, analysis, and improvement
40ISO 9000????
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41ISO 9000????
42The Malcolm Baldrige National Quality Award,MBNQA
- 1987?8?20???
- ??? The National Bureau of Standards and
Technology,NIST) - ??
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- ?????
- ?????????????
- ????????????
43The Malcolm Baldrige National Quality Award,MBNQA
cont.
- ??????
- ???
- ???
- ????
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- ???
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44MBNQA ??????
45MBNQA ????/???????
1. ???? 120
1.1 ?????? 80
1.2 ?????????? 40
2. ???? 85
2.1 ?????? 40
2.2 ???? 45
3. ??????? 85
3.1 ??????? 40
3.2 ??????????? 45
46MBNQA ????/??????? count.
4. ????? 90
4.1 ?????????? 50
4.2 ???? 40
5. ?????? 80
5.1 ???? 35
5.2 ?????????? 25
5.3 ???????? 25
47MBNQA ????/??????? count.
6. ???? 85
6.1 ?????????? 45
6.2 ??????? 25
6.3 ??????? 15
7. ???? 450
7.1 ?????? 125
7.2 ??????? 125
7.3 ?????? 80
7.4 ???? 120
?? 1000
48Six Sigma (Motorola,1980)
- Meaning3.4ppm defective
- 99???
- ??????????
- ???????????
- ???????????
- ???????(DMAIC)
- ??(Define)
- ??(Measure)
- ??(Analyze)
- ??(Improve)
- ??(Control)
49The Process Improvement Triad DFSS, Lean, and
DMAIC
OVERALL PROGRAMS
Lean
DMAIC
DFSS
ELIMINATE WASTE, IMPROVE CYCLE TIME
DESIGN PREDICTIVE QUALITY INTO PRODUCTS
ELIMINATE DEFECTS, REDUCE VARIABILITY
Lead-time
Capable
Robust
Design for Six Sigma
LEAN
Variation Reduction
- Predictability
- Feasibility
- Efficiency
- Capability
- Accuracy
- Flow Mapping
- Waste Elimination
- Cycle Time
- WIP Reduction
- Operations and Design
- Requirements allocation
- Capability assessment
- Robust Design
- Predictable Product Quality
The I in DMAIC may become DFSS
50Six Sigma
- DMAIC is closely related to the Shewhart cycle
(variously called the Deming cycle, or the PDCA
cycle)
51Quality versus Productivity
- Productivity
- Do things right. (efficiency)
- Quality
- Do the right things. (effectiveness)
52??
- ???????25?? vs. ????????33??
53The 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.
54Quality 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
55Quality Costs
56Legal Aspects of Quality
- The re-emergence of quality assurance as an
important business strategy is in part a result
of - Consumerism
- Product Liability
57??
58Legal Aspects of QualityConsumerism
- The explosion in the number of products.
- Consumer tolerance for minor defects and
aesthetic problems has decreased considerably.
59??
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60Legal Aspects of Quality Product Liability
- The legal obligation of manufacturers and sellers
to compensate for injury or damage caused by
defective products.
61??
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- ???????????
62Principles of Strict Liability
- A strong responsibility for both manufacturer and
merchandiser, requiring immediate responsiveness
to unsatisfactory quality through product
service, repair, or replacement of defective
product. - All advertising statements must be supportable by
valid company quality of certification data.
63??
- ???????? vs. ???????
- ??????????????,??????????
64Implementing Quality Improvement
- Recognition of the dimensions of quality by
management and the selection of dimensions along
which the business will compete - Selection of suppliers based on quality,
schedule, and cost, rather than on cost alone - Quality improvement must be a total, company-wide
activity - Top management commitment
- All the individuals in the organization have an
understanding of the basic tools of quality
improvement