IE 331 Statistical Quality Control Prepared by Dr. Mohamed Abdel Fattah Sharaf King Saud university College of engineering Industrial engineering Department

Part 1 Concepts of Quality

The Dialectic of Quality A continuous learning cycle: thesis meets antithesis and creates synthesis. Product Standards Statistical Methods Quality Control Customer Focus Quality Assurance Human Factors Quality Engineering Process Analysis Quality Management Systems Engineering Six Sigma

Traditional Definition Quality means “fitness for use” Quality of design Size, Power, Materials Quality of conformance (meeting specs) Manufacturing process Training/supervision

A Better Definition Quality means “fulfilling customer expectation” Allows for comparison of different items Places the customer as the judge Eliminates focus on meeting specs So What Do Customers Want? PERFECT! – Defect free FREE! – Low cost NOW!

Quality Costs

Quality costs escalate as value is added to product or service: Supplier Inspection Incoming Inspection Fabrication Inspection Subproduct Test Final Product Test Field Service $3 $30 $300 Cost of finding and correcting a defective component

Quality Costs Prevention costs: process/product design, training, vendor relations; Appraisal costs: quality audits, statistical quality control; Correction costs (internal failure): yield losses, rework charges; Recovery costs (external failure): returns, repairs, lost business. Costs associated with quality:

The Value Equation Quality

Why Quality is Critical

Quality: Quality is the single most important thing you can work on to improve the effectiveness of your company. It's as simple as that. Things just cascade when you get control of your quality. John Young, CEO Hewlett Packard Micro-economic interpretation: Quantity Price DemandSupply Quality affects both!

The Competition The Japanese are headed for world quality leadership and will attain it in the next two decades because no one else is moving there at the same pace. J.M Juran, 1967 IBM decided to have some parts manufactured in Japan as a trial project. In the specifications, they set the limit of defective parts at three units per 10,000. When the shipment arrived from Japan, it included this letter: “We Japanese have hard time understanding North American business practices. But the three defective parts per 10,000 have been included and are wrapped separately. Hope this pleases.” Toronto Sun

Dimensions of Quality

Eight Dimensions of Quality 1. Performance –the primary operating characteristics of the product or service. 2. Features –the characteristics that supplement the basic functioning of the product or service. 3. Reliability –probability of the product or service failing within a specified period of time. 4. Conformance –the degree to which a product or service meets acknowledged standards

Eight Dimensions of Quality 5. Durability –a measure of product life (both technical and economic). 6. Serviceability –the speed, courtesy, competence, and ease of repair or recovery. 7. Aesthetics –how a product or service looks, feels, sounds, tastes, or smells. 8. Perceived Quality –various tangible and intangible aspects of the product from which quality is inferred.

Service Quality

Dimensions of Service Quality Tangibles –Appearance of facilities, equipment, personnel… Reliability –Promised service dependably and accurately Responsiveness –Willingness to help, prompt service Assurance –Knowledge, courtesy, trust, confidence Empathy –Caring, individualized attention

Service Quality Gap Model Five ways service quality can fail...

Service Quality Gap Model Word of MouthPersonal NeedsPast Experience Expected Service Perceived Service Service Delivery Translate Perceptions to Specifications Perceptions of Customer Expectations External Communications Customer Organization

Service Quality Gap Model Word of MouthPersonal NeedsPast Experience Expected Service Perceived Service Service Delivery Translate Perceptions to Specifications Perceptions of Customer Expectations External Communications Customer Organization

Word of MouthPersonal NeedsPast Experience Expected Service Perceived Service Service Delivery Translate Perceptions to Specifications Perceptions of Customer Expectations External Communications Customer Organization Gap 1 Service Quality Gap Model

Word of MouthPersonal NeedsPast Experience Expected Service Perceived Service Service Delivery Translate Perceptions to Specifications Perceptions of Customer Expectations External Communications Customer Organization Gap 1 2 Service Quality Gap Model

Word of MouthPersonal NeedsPast Experience Expected Service Perceived Service Service Delivery Translate Perceptions to Specifications Perceptions of Customer Expectations External Communications Customer Organization Gap Service Quality Gap Model

Word of MouthPersonal NeedsPast Experience Expected Service Perceived Service Service Delivery Translate Perceptions to Specifications Perceptions of Customer Expectations External Communications Customer Organization Gap Service Quality Gap Model

Word of MouthPersonal NeedsPast Experience Expected Service Perceived Service Service Delivery Translate Perceptions to Specifications Perceptions of Customer Expectations External Communications Customer Organization Gap

Quality Pioneers

Quality Pioneers & Gurus Early American Industry Pioneers –Walter Shewhart–Control Charts –Dodge & Romig–Acceptance Sampling –Arnold Feigenbaum–Total Quality Management Post W.W.II / Japanese Quality Gurus –W. Edwards Deming–Total Quality Management –Joseph Juran–The cost of quality –Philip B. Crosby–Quality is free –Masaaki Imai–Kaizen –Kaoru Ishikawa–TQM-Japanese style

Deming

W. Edwards Deming 1900 to 1993 Trained as a physicist Master of Science -- CU Taught SQC during World War II Went to Japan in 1946 Brought SQC to Japan Enthusiastically adopted by Japanese

Deming’s Theory of Quality & Economics Improve Quality Costs decrease because of less rework, fewer mistakes, fewer delays, snags; better use of machine-time and materials Productivity Improves Capture the market with better quality and lower price Stay in business Provide jobs and more jobs

Deming’s 14 Points 1.Constancy of purpose 2.New philosophy 3.Cease inspection 4.Move beyond price 5.Improve constantly 6.Job training 7.Modern supervision 8.Drive out fear 9.Break down barriers 10.Eliminate slogans… 11.Eliminate quotas 12.Promote pride 13.Education & retraining 14.Top management commitment

Deming Improvement Cycle ActPlan DoCheck

Deming Improvement Cycle ActPlan DoCheck Continuous Improvement ActPlan DoCheck ActPlan DoCheck

Japanese Deming Prize Established 1951 Annual prize Awarded for –development of quality tools, or –quality improvement programs Created by JUSA (Union of Japanese Scientists and Engineers