ie 331 statistical quality control prepared by dr. mohamed abdel fattah sharaf king saud university...
Post on 28-Dec-2015
242 Views
Preview:
TRANSCRIPT
IE 331
Statistical Quality Control
Prepared byDr. Mohamed Abdel Fattah Sharaf
King Saud universityCollege 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
CustomerFocus
QualityAssurance
HumanFactors
QualityEngineering
ProcessAnalysis
QualityManagement
SystemsEngineering
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
• 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:Costs associated with quality:
The Value Equation
price
yFlexibilitTimelinessQualityValue
Quality
Why Quality is Critical
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 Demand Supply
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 Mouth Personal Needs Past Experience
Expected Service
Perceived Service
Service Delivery
Translate Perceptionsto Specifications
Perceptions ofCustomer Expectations
External Communications
Customer
Organization
Service Quality Gap Model
Word of Mouth Personal Needs Past Experience
Expected Service
Perceived Service
Service Delivery
Translate Perceptionsto Specifications
Perceptions ofCustomer Expectations
External Communications
Customer
Organization
Word of Mouth Personal Needs Past Experience
Expected Service
Perceived Service
Service Delivery
Translate Perceptionsto Specifications
Perceptions ofCustomer Expectations
External Communications
Customer
Organization
Gap 1
Service Quality Gap Model
Word of Mouth Personal Needs Past Experience
Expected Service
Perceived Service
Service Delivery
Translate Perceptionsto Specifications
Perceptions ofCustomer Expectations
External Communications
Customer
Organization
Gap 1
2
Service Quality Gap Model
Word of Mouth Personal Needs Past Experience
Expected Service
Perceived Service
Service Delivery
Translate Perceptionsto Specifications
Perceptions ofCustomer Expectations
External Communications
Customer
Organization
Gap 1
2
3
Service Quality Gap Model
Word of Mouth Personal Needs Past Experience
Expected Service
Perceived Service
Service Delivery
Translate Perceptionsto Specifications
Perceptions ofCustomer Expectations
External Communications
Customer
Organization
Gap 1
2
3
4
Service Quality Gap Model
Service Quality Gap Model
Word of Mouth Personal Needs Past Experience
Expected Service
Perceived Service
Service Delivery
Translate Perceptionsto Specifications
Perceptions ofCustomer Expectations
External Communications
Customer
Organization
Gap 1
2
5
3
4
Quality Pioneers
Quality Pioneers & GurusQuality 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 fear9. Break down barriers10.Eliminate slogans…11.Eliminate quotas12.Promote pride13.Education &
retraining14.Top management
commitment
Deming Improvement Cycle
Act Plan
DoCheck
Deming Improvement Cycle
Act
Plan
Do
Check
Continuous Improvement
ActPlan
Do
CheckA
ctP
lanDo
Check
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
top related