- Slides: 27
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) Quality Control
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 Quality Control
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 Quality Control 5
• 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. ” Quality Control
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 Quality Control 7
Formula for quality: Quality = Performance Expectation Quality Control
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
Quality Control • 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: • • 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. Quality Control
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 Quality Control 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: – – 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 Quality Control
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. Quality Control
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. Quality Control
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) Quality Control