Transcript Quality Basics

Quality Basics
Lecture One
Quality Control
DEFINING QUALITY
• A study that asked managers of 86 firms in the
United States to defined quality produced several
dozen different responses, including the following
• Perfection
• Consistency
• Eliminating waste
• Speed of delivery
• Compliance with polices and procedures
• Providing a good,usable product
• Do it right the first time
• Delighting or pleasing customers
• Total Customer service and satisfaction.
Defining Quality
• “Quality is a subjective term for which each
person has his or her own definition”(ASQ)
• Quality is conformance to requirements or
specifications. (Crosby 1979)
• Quality is fitness for use. (Juran 1974)
• The quality of a product or service is the fitness
of that product or service for meeting its
intended used as required by the customers.
(Hence)
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Defining Quality
• In technical usage, quality can have two
meanings:
– the characteristics of a product or service that
bear on its ability to satisfy stated or implied
needs, and
– a product or service free of deficiencies
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Defining Quality - “Gurus”
• W. Edwards Deming - “non-faulty
systems”
– Out of the Crisis
• Joseph M. Juran - “fitness for use”
– Quality Control Handbook
• Philip B. Crosby - “conformance to
requirements”
– Quality is Free
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• Armand Feigenbaum – author: Total Quality Control (1961)
– “quality is a customer determination based
on the customer’s actual experience with the
product or service, measured against his or
her requirements - stated or unstated,
conscious or merely sensed, technically
operational or entirely subjective - and
always representing a moving target in a
competitive market.”
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Defining Quality- Different Views
• Customer’s view (more subjective)
– the quality of the design (look, feel, function)
– product does what’s intended and lasts
• Producer’s view
– conformance to requirements (Crosby)
– costs of quality (prevention, scrap, warranty)
– increasing conformance raises profits
• Government’s view
– products should be safe
– not harmful to environment
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Formula for quality:
Quality =
Performance
Expectation
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Quality Characteristics
• Quality Characteristic may be one or more elements which define
the intended quality level of a product or service. Several grouping
of these characteristics can be formed in:
• Structural characteristics
include such elements as the length of a part, the weight of a can,
the strength of a beam, the viscosity of a fluid, and so on.
• Sensory characteristics
include the taste of good food, the smell of a sweet fragrance, and
the beauty of a model, among others.
• Time-oriented characteristics
include such measures as a warranty, reliability, and maintainability.
• Ethical characteristics
include honesty, courtesy, friendliness, and so on.
Variables and Attributes
• Variables - characteristics that are measurable and are
expressed on a numerical scale.
• Nonconformity - is a quality characteristic that does
not meet its stipulated specifications requirement.
• Nonconforming - unit is one that has one or more
nonconformities such that the unit is unable to meet the
intended standards and is unable to function as
required.
• Attribute a quality characteristics if it can be classified
as either conforming or nonconforming to a stipulated
specifications requirement.
Standard or Specification
•
Specification:
a set of conditions and requirements of specific and limited application,
that provide a detailed description of the procedure, process, material,
product, or service for use primarily in procurement and
manufacturing. Standards may be referenced or included in a
specification.
•
Standard:
a prescribed set of conditions and requirements, of general or broad
application, established by authority or agreement, to be satisfied by a
material, product, process, procedure, convention, test method; and/or
the physical, functional, performance, or conformance characteristics
thereof. A physical embodiment of a unit of measurement ( for
example, an object such as the standard kilogram or an apparatus
such as the cesium beam clock).
The Three Aspects of Quality
• Quality of Design
Quality of design deals with the rigid conditions that the product or
service must minimally possess in order to satisfy the requirements
of the customer. It implies that the product or service must be
signed to meet at least minimally the needs of the consumer.
• Quality of Conformance
Quality of conformance implies that the manufactured product or the
service rendered must meet the standards selected in the design
phase.
• Quality of Performance
Quality of performance is concerned with the operation of the
product when actually put to use or the service when performed and
measures the degree to which it satisfies the consumer
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• Quality control may generally be defined as a system
that is used to maintain a desired level of quality in a
product or service.
• This task may be achieved through different measured
such as:
• planning
• design
• use of proper equipment and procedures
• inspection
• taking corrective action in a case a deviation is observed
between the product, service, or process output and a
specified standard.
Benefits of Quality Control
The advantages of a quality control system, however, become obvious
in the long run.
• First, the improvement in the quality of products and services.
• Second, the system is continually evaluated and modified to meet
the changing needs of the customer.
• Third, a quality control system improves productivity, which is one
of the goals of all organizations.
• Fourth, such a system reduces costs in the long run.
• Fifth, with improved productivity, the lead time on the production of
parts and subassemblies is reduced, which may result in an
improvement in meeting customer due dates
• Keeping the customers satisfied is a fundamental goal.
• A company that adopts this philosophy and uses a quality control
system to help in meeting this objective is one that will be
competitive for a long time.
Quality Assurance:
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Quality assurance is the process of verifying or determining whether
products or services meet or exceed customer expectations. Quality
assurance is a process-driven approach with specific steps to help define
and attain goals. This process considers design, development, production,
and service.
The most popular tool used to determine quality assurance is the Shewhart
Cycle, developed by Dr. W. Edwards Deming. This cycle for quality
assurance consists of four steps: Plan, Do, Check, and Act. These steps
are commonly abbreviated as PDCA.
The four quality assurance steps within the PDCA model stand for:
Plan: Establish objectives and processes required to deliver the desired
results.
Do: Implement the process developed.
Check: Monitor and evaluate the implemented process by testing the
results against the predetermined objectives
Act: Apply actions necessary for improvement if the results require
changes.
– Reliability, Responsiveness, Assurance, Empathy, Tangibles
Difference between QC & QA
• Often, quality control is confused with quality assurance. Though
the two are very similar, there are some basic differences.
• Quality control is concerned with the product, while quality
assurance is process–oriented.
• Even with such a clear-cut difference defined, identifying the
differences between the two can be hard. Basically, quality control
involves evaluating a product, activity, process, or service. By
contrast, quality assurance is designed to make sure processes are
sufficient to meet objectives. Simply put, quality assurance ensures
a product or service is manufactured, implemented, created, or
produced in the right way; while quality control evaluates whether
or not the end result is satisfactory.
Value-based Approach
• Manufacturing dimensions
– Performance: based on primary characteristic of a product
– Features: Features of the product are those secondary characteristic that
supplement product’s basic functioning
– Reliability: Refers to the probability of product’s
malfunctioning or failing
within the specific period of time
– Conformance:
Refers to degree or extent to which product's design or
operating characteristic meet pre established standards)
– Durability: Means length of time a product will last or product life)
– Serviceability: Refer to the speed, courtesy competence and ease of
repair of a product)
– Aesthetics: Refer to how a product looks ,feel, sounds, tastes or smells.
– Perceived quality: Refers to what customer perceived to be the quality
of a product based on image, advertising and brand name reputation.
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Value-based Approach
• Service dimensions
– Reliability
Ability to perform the promised service dependably and accurately.
– Responsiveness
Willingness to help customers and provide prompt service.
– Assurance
Knowledge and courtesy of employees and their ability to inspire trust
and confidence.
– Empathy
Caring, individualized attention the firm provides its customers.
– Tangibles
Appearance of physical facilities, equipment, personnel, and
communication materials.
Shift to Quality
Isolated
Economies
Focus on
quantity
Pre-World War II
Period of
change from
quantity to
quality
1945
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Global
Economy
Focus on
quality
1990’s
History of Quality Paradigms
• Customer-craft quality paradigm:
– – design and build each product for a particular customer.
– – producer knows the customer directly.
• Mass production and inspection quality paradigm:
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focus on designing and building products for mass consumption.
larger volumes will reduce costs and increases profits.
push products on the customer (limit choices).
quality is maintained by inspecting and detecting bad products.
• TQM or “Customer Driven Quality” paradigm:
– potential customers determine what to design and build.
– higher quality will be obtained by preventing problems
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Need for a New Strategy
• Foreign markets have grown
– Import barriers and protection are not the
answer.
• Consumers are offered more choices
– They have become more discriminating.
• Consumers are more sophisticated
– They demand new and better products.
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Why Quality Improvement?
• Global Competition
– Economic and political boundaries are slowly
vanishing
• It pays
– Less rework, fewer mistakes, fewer delays,
and better use of time and materials
– In United States today, 15 to 20% of the
production costs are incurred in finding and
correcting mistakes.
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How Do Organizations
Compete?
• Most common competitive measures:
– Quality (both real and perceived)
– Cost
– Delivery (lead time and accuracy)
• Other measures
– safety,
– employee morale,
– product development (time-to-market,
innovative products)
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