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QUALITY MANAGEMENT. EVOLUTION OF QUALITY MANAGEMENT . INSPECTION QUALITY CONTROL QUALITY ASSURANCE TOTAL QUALITY MANAGEMENT. Definition of Quality. As per ISO:9001-2000 : “Quality is the degree to which a set of inherent characteristics fulfils requirements .”
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QUALITY MANAGEMENT EVOLUTION OF QUALITY MANAGEMENT. • INSPECTION • QUALITY CONTROL • QUALITY ASSURANCE • TOTAL QUALITY MANAGEMENT
Definition of Quality As per ISO:9001-2000 : “Quality is the degree to which a set of inherent characteristics fulfils requirements.” • Characteristics may be – physical, sensory, behavioural, temporal, ergonomic, functional,etc. • Requirements may be – for organizations, for customers, for interested parties, etc.
Defining Quality The quality of a product or service is the fitness of that product or service for meeting or exceeding its intended use as required by the customer.
Quality Control Quality Control is essentially the activities and techniques employed to achieve & maintain the quality of a product, process or service. It involves the monitoring activity, but also concerns finding & eliminating causes of quality problems so that requirements of customers are continuously met.
Quality control & Inspection • Inspection is concerned with ‘sentencing’ the product asgood or bad, by comparison with the standard. • Quality Control is concerned with feedback of the comparative information in order to regulate the process. ‘Sentencing’ may also be involved, but ideally the limits are set so that the process can be adjusted before product from the process reaches the limit where it has to be rejected.
Quality control & Inspection Pass Process Acceptance Process Comparison With standard (Inspection) Fail Rejection (Scrap or Rework Inspection Continue Process Comparison with standard for QC FEEDBACK to regulate process Quality control
Quality control Aim of quality control is to produce better quality; QC determines the causes of variations; QC determines what, when & how much to inspect. Inspection Inspection is a tool to achieve this; Inspection determines acceptability comparing with limits of variability; Inspection actually conducts examination of goods for quality characteristics. Quality Control vs Inspection
Inspection Planning • Consists of six basic elements : • What to inspect – specifications are the tools of inspection ; • When to inspect – stages ofinspection like, ‘First off inspection’, ‘Pilot piece inspection’, ‘Patrolling inspection’, ‘critical operation inspection’, ‘appraisal inspection’, ‘salvage inspection’ ,etc., • Where to inspect – includes : • Receiving inspn – to ensure that incoming product is inspected or otherwise verified as conforming to specified requirements; • In-process inspn. – to inspect product, as required by quality plan or documented procedures, by use of process monitoring & control methods; • Final inspn. – to carry out all final inspection in accordance with quality plan or documented procedures to complete the evidence of conformance of finished product.
Quality Assurance Quality assurance is broadly the prevention of quality problems through planned and systematic activities including documentation. This will Include : • Establishment of a good quality management system and the assessment of its adequacy audit of the operation of the system and review of the system itself.
Total Quality Management (TQM) TQM is an approach to improve the effectiveness and flexibility of businesses as a whole. It is essentially a way of organizing & involving the whole organization, every department , every activity, every single person at every level. For an organization to be effective, each part of it must work properly together, recognizing that every Person and every activity affects, & in turn, is affected by others.
Quality in Manufacturing operations • Manufacturing operations thru’ ‘chemical’ or ‘physical’ process transform inputs into ‘tangible’ products; • ‘Quality’ for products is ‘conformance to requirements’ or ‘conformance to specifications’ ; • Manufacturing should be done in accordance with ‘drawings / specifications’’ to have ‘acceptance/rejection criteria’ and under ‘controlled conditions’ ; • Quality controls should be applied to • - Process, • - Procedure, • - System, • - Inspection; • ‘Standards’ for comparison & corrective action.
Quality in Manufacturing operations • Product attributes represent ‘what’ is delivered & can be measured after the output has been delivered. • David Gavin defined 8 dimensions that can be used at a strategic level to analyze product quality: • a). Performance, g). Aesthetics, • b). Features, h). Perceived quality • c). Reliability, (Reputation) • d). Conformance, • e). Durability, • f). Serviceability,
Quality in Service operations • ‘Service quality’ is variously defined, but essentially, is to do with meeting customer needs and requirements and how well the service level delivered, matches customers’ expectations. • Two types of services : • a). ‘Material’ services – related to with ‘things’, such • as, distributing & delivering goods; e.g. postal service. • b). ‘Personal’ service - Related to human interface & • interaction ; e.g. health care, etc. • ‘Material’ content of a service : on one end, heavily product-oriented; on the other end, material-content less, service more; and in-between, though material involved to a large extent, service determines repeatability.
Quality in Service operations • ‘Personal’ content of service – where ‘service’ is directly delivered by a person to a person. • Ten determinants of ‘Service’ quality: • 1). Reliability, 7). Credibility, • 2). Responsiveness, 8). Security, • 3). Competence, 9). Understanding, • 4). Accessibility, 10). Tangibles. • 5). Courtesy, • 6). Communication,
Quality in Service operations • Measurement of Service quality : comparison between consumers’ expectation with their perceptions of actual service delivered ; • Monitoring Service quality : systems to measure & monitor success using : • - focus groups, • - discussion, • - survey, • - interviews, • - mystery shoppers, etc. • To achieve ‘zero-defects’ with sophisticated techniques & personnel policies ; • Links between ‘customer retention’ & ‘profitability’ and ‘lifetime value’ of retained customers.
Measures of Quality Product & Quality Process : Cost Of Quality • The language of money serves as the basic medium for assessing economic achievement. Organizations communicate results in monetary terms. • The basis of the interest and value of COQ measures is a manager’s desire to understand what the delivery of the product or Service costs. • COQ is critical in guiding the organization toward profitability. • The traditional COQ model states that costs can be divided into two broad categories : Conformance & Non-conformance costs.
COQ (PAF Model) • Conformance costs are those costs incurred to ensure that the manufactured products or delivered services conform to specifications. These costs are of two types : • Prevention Costs – associated with all activities • designed to prevent defects in products or service. • Appraisal Costs – associated with measuring and • evaluating the product or service quality to ensure conformance. • Non-conformance costs are associated with products or services that do not conform to the customers’ requirements. They are referred to as Failure costs: • Internal Failure costs – incurred prior to shipment of the product or delivery of service. • External Failure costs – of discovered defects after delivery of products or service.
Causes of Process Variability • Variation exists in the characteristics of all materials, articles, services and people. • Inherent variability in every transformation process, causes output to vary over a period of time. • Certain variations belong to the category of Chance or random variations about which little may be done. • When random variation alone exists, it may not be possible to trace to a single cause. • When only random variations are present in a process, the process is said to be under statistical control.
Contd. • Causes of variations, which are relatively large in magnitude and identifiable, are classified as ‘assignable or specific causes’. • These consist of differences among plant,processes, equipment, operators,information,materials and other miscellaneous factors. • When ‘assignable’ causes of variations are present, process variability becomes excessive and the process is classified as ‘out of control’.
Contd. • The above leads to two questions: • Is the process stable or out of control ? It means – the process variability is due to ‘chance’ or ‘assignable’ variations. • What is the extent of process variability ? It means – to assess natural capability of the process when only random causes of variations are present.
Statistical Quality Control • Statistics is called as the science of variations. • SQC is to devise methods/ techniques for separating allowable variations from preventable variations. • Statistical techniques are applied to three major types of applications in the field of quality control : • Statistical process control (SPC) to monitor critical parameters of process with the objective of keeping them within the desired levels.
Contd. • Statistics may be applied in acceptance sampling with the objectives of screening batches of items that contain an ‘unacceptable’ number of defective items from ‘acceptable’ batches. • Statistical techniques can be used to analyze and improve Quality levels e.g. - Histograms, - Correlation / Regression, - Design of experiments, etc.
Contd. • Statistical process control (SPC) relies on control Charts & limits to indicate the adequate performance of the processes that produced the measured characteristics. • Control charts are : • X-R chart for mean and range; • P – chart for fraction defectives; • C – chart for defects per unit.