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IENG 486 - Lecture 03. Introduction to Statistical Process Control. Assignment:. Print off Review Data from link on Materials pg. Bring the data and your exam calculator to next class Reading: Chapter 1: (1.1, 1.3 – 1.4.5)
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IENG 486 - Lecture 03 Introduction to Statistical Process Control IENG 486: Statistical Quality & Process Control
Assignment: • Print off ReviewData from link on Materials pg. • Bring the data and your exam calculator to next class • Reading: • Chapter 1: (1.1, 1.3 – 1.4.5) • Cursory – get Fig. 1.12., p.34; Deming Management,1.4.4 Liability • Chapter 2: (2.2 – 2.7) • Cursory – Define, Measure, Analyze, Improve, Control • Chapter 3: (3.1, 3.3.1, 3.4.1) • HW 1: Chapter 3 Exercises: • 1, 3, 4 – using exam calculator • 10 (use Normal Plots spreadsheet from Materials page) • 43, 46, 47 (use Exam Tables from Materials page – Normal Dist.) IENG 486: Statistical Quality & Process Control
Meaning of Quality and Quality Improvement • Quality – one of most important consumer decision factors in selecting products and services • Understanding / improving quality is key factor for success, growth, and competitive position • Substantial return on investment comes from: • Improved quality • Successful implementation of quality techniques as overall business strategy IENG 486: Statistical Quality & Process Control
Review the Red Bead Experiment • Managemement Actions: • Training: (operationally required) • Goal Setting: Zero Defects! (visible, group) • Marketing Slogan : Quality is Job #1 (all on message) • Employee of the Week Parking Spot: (Single Reward / Equity Theory) • Incentive Pay: (Herzberg Motivator/Demotivator) • Personal Stretch Goals: X Defects or Less! / Expectancy Thry • Firing the Weakest Links: (Negative Reinforcement) • Outside Consultant: (Benchmarking / Best Practices) • Self-Managed Teams: (two weeks – not true self-mgt) • MBA-style Productivity Improvement: (Fire ½, 2X shifts / 50% improvement) • Move Offshore: (Portable MBA / golden parachute) • Why didn’t these work? • Science of Quality (systems) was not addressed! IENG 486: Statistical Quality & Process Control
Dimensions of Quality • Performance – Will the product do the intended job? • Reliability – How often does the product fail? • Durability - How long does the product last? • Serviceability – How easy is it to repair the product? • Aesthetics – What does the product look like? • Features – What does the product do? • Perceived quality – What is the reputation of the company or product? • Conformance to standards – Is the product made exactly as the designer intended? IENG 486: Statistical Quality & Process Control
Quality is a multifaceted entity. • Traditional (OLD) definition of Quality: • Fitness of use(i.e., products must meet requirements of those who use them.) IENG 486: Statistical Quality & Process Control
Two Aspects of “Fitness for Use” • Quality of design – • all products intentionally made in various grades of quality. (e.g., Autos differ with respect to size, options, speed, etc.) • Quality of conformance – • how well the product conforms to specifications. (e.g., If diameter of a drilled hole is within specifications then it has good quality.) IENG 486: Statistical Quality & Process Control
What's Wrong with "Fitness for Use" Definition of Quality? • Unfortunately, quality as “Fitness for Use” has become associated with the "conformance to specifications" regardless if product is "fit for use" by customer. • Misconception: • Quality can be dealt with solely in manufacturing - that is, by "gold plating" the product IENG 486: Statistical Quality & Process Control
Modern Definition of Quality:Quality is inversely proportional to variability • If variability of product decreases quality of product increases • Quality Improvement – • Reduction of variability in processes and products • Quality Engineering – • Set of operational, managerial, and engineering activities that a company uses to ensure that quality characteristics of a product are at nominal levels IENG 486: Statistical Quality & Process Control
Statistical Methods for Quality Improvement • Relative Savings from $1 invested in: • Acceptance Sampling ($1) • On-Line Process Control ($10) • Off-Line Process Improvement ($100) IENG 486: Statistical Quality & Process Control
Acceptance Sampling • Reduces bad product sent to consumer • Dodge & Romig 1930s • Sample from lot to determine acceptance • More effective than 100% inspection • No feedback, prevention or improvement IENG 486: Statistical Quality & Process Control
On-Line Process Control • Monitoring of manufacturing process with control charts • Shewhart 1920s • Sample & stop process if necessary • No improvement, but maintains current process quality level IENG 486: Statistical Quality & Process Control
Off-Line Improvement • 7 Tools of Ishikawa • DMAIC process • Designed experiments • Taguchi & Classical Statistics 1980s • If it's not broke, improve it! • Continuous improvement of product designs and manufacturing processes IENG 486: Statistical Quality & Process Control
Total Cost Failure Cost $ Quality Cost Defect Rate Quality Myth:Higher Quality Higher Cost IENG 486: Statistical Quality & Process Control
Manufacturing Process $20 / part 100 parts 75% Conform (75 good parts) 25% Non-conforming: (10 scrap parts) Re-work Process $4 / part (15 good parts) Very Often:Higher Quality Lower Cost • Textbook ex: Manufacture of Copier Part (25 parts) (40% Scrap, 60% Re-workable) IENG 486: Statistical Quality & Process Control
Study finds excessive process variability responsible for high nonconformity rate • New SQC procedure implemented • NOW: manufacturing non-conformity = 5% • SAVINGS: $22.89 – $20.53 = $2.36 / good part • PRODUCTIVITY: 9% improvement IENG 486: Statistical Quality & Process Control
Tactical less inspection less scrap and rework more capacity easier scheduling & shorter lead time less inventory less warranty cost Strategic more flexibility to make new products customer satisfaction easier to spot and solve problems employee involvement in continuous improvement How Quality Engineering Makes a Company More Competitive IENG 486: Statistical Quality & Process Control
Taguchi (1980) and Robust Design • New Goal: consistently good performance in a variety of operating conditions • Minimize variation in processes and products • Use Designed Experiments to achieve robustness IENG 486: Statistical Quality & Process Control
Prod Y Taguchi's Example:Elasticity of Caramel • Product X conforms to elasticity spec at 72o • Product Y performs well in a wide variety of operating conditions Prod X Elasticity Spec 72o Temp IENG 486: Statistical Quality & Process Control
Total Quality Management – TQM • Although statistical techniques are critical for quality improvement: • the management system must direct quality improvement philosophy and ensure its implementation in all aspects of business • TQM must be implemented within a management system that is scientifically quality driven IENG 486: Statistical Quality & Process Control
International Standards Organization ISO 9000 (1990s) • An ISO 9000 certified company • examined by a registered official • has an effective management system, capable of consistent performance • Examples: • System in place to correctly identify customer needs • Staff have correct versions of documentation • Preferred suppliers selected; consistent communication system • System to document and correct errors IENG 486: Statistical Quality & Process Control
Six Sigma - Motorola • Six Sigma = 2 defects per billion opportunities! • Motorola 6 sigma*: 3.4 defects per billion, with 1.5 σ shift* • Every employee must show bottom line results of quality project – finance, mail room, manufacturing, etc. • identify problem; • develop measurement; • set goal; • close gap • Long term process – 5 years to fully implement IENG 486: Statistical Quality & Process Control
Malcolm Baldridge National Quality Award • Established by congress in 1987, for excellence in organizations • Applicant receives intense investigation • NIST (National Institute of Standards and Technology) study shows Baldrige Award recipients outperformed the Standard & Poor’s 500 by nearly 2.5 to 1. IENG 486: Statistical Quality & Process Control
The Baldridge Award examines quality of organization in seven categories • Leadership • Information and Analysis • Strategic Planning • Human Resource Development and Management • Process Management • Business Results • Customer Focus and Satisfaction IENG 486: Statistical Quality & Process Control
DMAIC Process • Define – Performance of System • Project Charter / Suppliers, Inputs, Process, Outputs, Customers (SIPOC) • Measure – Critical-to-Quality variables (CTQs) • KPIV / KPOV – and measurement system’s capability • Analyze – Data-driven vs Attribution Theory • Tools from this course – and track the project, too! • Identify Common Causes and Assignable Causes of variation • Improve – Documented (Engineering) Solution • Pilot / Confirmation testing • Control – Incorporate the good / eliminate the bad • Sustain the improvement – track this! • Project-Basis– Management Control • Value Opportunity • Dashboard Variables IENG 486: Statistical Quality & Process Control