quality management

Module -IV

CHAPTER-17 & 24 – ASWATHAPPA (HPH)CHAPTER -3 RUSSEL AND TAYLOR (WILEY)

CH-9 AND 9A – CHASE AQUILANO AND JACOBS , SHANKAR (TMH)

Open source for Safety Management

What is quality?• Quality, simplistically, means that a product should meet its

specification.

Types of Quality

The Quality Cycle

Quality management activities• Quality assurance

– Establish organisational procedures and standards for quality.• Quality planning

– Select applicable procedures and standards for a particular project and modify these as required.

• Quality control– Ensure that procedures and standards are followed by the software

development team.• Quality management should be separate from project

management to ensure independence.

Copyright 2006 John Wiley & Sons, Inc.

3-6

Meaning of Quality Webster’s Dictionary

degree of excellence of a thing American Society for Quality

totality of features and characteristics that satisfy needs

Consumer’s and Producer’s Perspective

Copyright 2006 John Wiley & Sons, Inc. 3-7

Meaning of Quality:Consumer’s Perspective

Fitness for use how well product or service

does what it is supposed to Quality of design

designing quality characteristics into a product or service

A Mercedes and a Ford are equally “fit for use,” but with different design dimensions


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Dimensions of Quality:Manufactured Products

Performance basic operating characteristics of a product; how well

a car is handled or its gas mileage Features

“extra” items added to basic features, such as a stereo CD or a leather interior in a car

Reliability probability that a product will operate properly

within an expected time frame; that is, a TV will work without repair for about seven years


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Conformance degree to which a product meets pre–established

standards Durability

how long product lasts before replacement Serviceability

ease of getting repairs, speed of repairs, courtesy and competence of repair person

Dimensions of Quality:Manufactured Products (cont.)


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Aesthetics how a product looks, feels, sounds, smells, or

tastes Safety

assurance that customer will not suffer injury or harm from a product; an especially important consideration for automobiles

Perceptions subjective perceptions based on brand name,

advertising, and the like

Dimensions of Quality:Manufactured Products (cont.)


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Dimensions of Quality:Service

Time and Timeliness How long must a customer wait for service, and is

it completed on time? Is an overnight package delivered overnight?

Completeness: Is everything customer asked for provided? Is a mail order from a catalogue company

complete when delivered?


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Dimensions of Quality:Service (cont.)

Courtesy: How are customers treated by employees? Are catalogue phone operators nice and are their

voices pleasant? Consistency

Is the same level of service provided to each customer each time?

Is your newspaper delivered on time every morning?


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Accessibility and convenience How easy is it to obtain service? Does a service representative answer you calls quickly?

Accuracy Is the service performed right every time? Is your bank or credit card statement correct every month?

Responsiveness How well does the company react to unusual situations? How well is a telephone operator able to respond to a customer’s

questions?

Dimensions of Quality:Service (cont.)


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Meaning of Quality:Producer’s Perspective

Quality of Conformance Making sure a product or service is produced

according to design if new tires do not conform to specifications, they

wobble if a hotel room is not clean when a guest checks in,

the hotel is not functioning according to specifications of its design


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Meaning of Quality:A Final Perspective

Consumer’s and producer’s perspectives depend on each other

Consumer’s perspective: PRICE Producer’s perspective: COST Consumer’s view must dominate


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Fitness forConsumer Use

Producer’s Perspective Consumer’s Perspective

Quality of Conformance

• Conformance to specifications

• Cost

Quality of Design

• Quality characteristics• Price

MarketingProduction

Meaning of Quality

Meaning of Quality


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Total Quality Management

• Commitment to quality throughout organization

• Principles of TQM– Customer-oriented– Leadership– Strategic planning– Employee responsibility– Continuous improvement– Cooperation– Statistical methods– Training and education


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Quality Gurus

• Walter Shewart– In 1920s, developed control charts– Introduced the term “quality assurance”

• W. Edwards Deming – Developed courses during World War II to teach statistical

quality-control techniques to engineers and executives of companies that were military suppliers

– After the war, began teaching statistical quality control to Japanese companies

• Joseph M. Juran– Followed Deming to Japan in 1954– Focused on strategic quality planning


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Armand V. Feigenbaum In 1951, introduced concepts of total quality control and

continuous quality improvement Philip Crosby

In 1979, emphasized that costs of poor quality far outweigh the cost of preventing poor quality

In 1984, defined absolutes of quality management—conformance to requirements, prevention, and “zero defects”

Kaoru Ishikawa Promoted use of quality circles Developed “fishbone” diagram Emphasized importance of internal customer

Quality Gurus (cont.)

Deming’s 14 Points


1. Create constancy of purpose2. Adopt philosophy of prevention3. Cease mass inspection4. Select a few suppliers based on quality5. Constantly improve system and workers


6. Institute worker training7. Instill leadership among supervisors8. Eliminate fear among employees9. Eliminate barriers between departments10. Eliminate slogans



11. Eliminate numerical quotas12. Enhance worker pride13. Institute vigorous training and education

programs14. Develop a commitment from top

management to implement above 13 points



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Deming Wheel: PDCA Cycle

1. PlanIdentify problem and develop plan for improvement.

2. DoImplement plan on a test basis.

3. Study/CheckAssess plan; is it working?

4. ActInstitutionalize improvement; continue cycle.


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TQM and…

• … Partnering– a relationship between a company and its

supplier based on mutual quality standards• … Customers

– system must measure customer satisfaction• … Information Technology

– infrastructure of hardware, networks, and software necessary to support a quality program


Quality Improvement and Role of Employees

• Participative problem solving– employees involved in

quality management – Example : every employee

has undergone extensive training to provide quality service to Disney’s guests


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PresentationImplementationMonitoring

SolutionProblem results

Problem AnalysisCause and effectData collection and analysis

Problem IdentificationList alternativesConsensusBrainstorming

TrainingGroup processesData collectionProblem analysis

Organization8-10 membersSame areaSupervisor/moderator

Quality Circle


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Strategic Implications of TQM

• Strong leadership• Goals, vision, or mission• Operational plans and policies• Mechanism for feedback


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Six Sigma

• A process for developing and delivering near perfect products and services

• Measure of how much a process deviates from perfection

• 3.4 defects per million opportunities (DPMO)• Champion

– an executive responsible for project success


Black Belts and Green Belts

• Black Belt– project leader

• Master Black Belt– a teacher and mentor

for Black Belts• Green Belts

– project team members


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3.4 DPMO

67,000 DPMOcost = 25% of sales

DEFINE CONTROLIMPROVEANALYZEMEASURE

Six Sigma: DMAIC


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TQM in Service Companies

• Principles of TQM apply equally well to services and manufacturing

• Services and manufacturing companies have similar inputs but different processes and outputs

• Services tend to be labor intensive• Service defects are not always easy to

measure because service output is not usually a tangible item


Quality Attributes in Service

• Benchmark– “best” level of quality

achievement one company or companies seek to achieve

• Timeliness– how quickly a service is

provided“quickest, friendliest, most

accurate service available.”


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Cost of Quality

• Cost of Achieving Good Quality– Prevention costs

• costs incurred during product design– Appraisal costs

• costs of measuring, testing, and analyzing• Cost of Poor Quality

– Internal failure costs• include scrap, rework, process failure, downtime, and

price reductions– External failure costs

• include complaints, returns, warranty claims, liability, and lost sales


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Prevention Costs• Quality planning costs

– costs of developing and implementing quality management program• Product-design costs

– costs of designing products with quality characteristics• Process costs

– costs expended to make sure productive process conforms to quality specifications

• Training costs– costs of developing and putting on quality training programs for

employees and management• Information costs

– costs of acquiring and maintaining data related to quality, and development of reports on quality performance


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Appraisal Costs

• Inspection and testing– costs of testing and inspecting materials, parts, and

product at various stages and at the end of a process• Test equipment costs

– costs of maintaining equipment used in testing quality characteristics of products

• Operator costs– costs of time spent by operators to gar data for testing

product quality, to make equipment adjustments to maintain quality, and to stop work to assess quality


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Internal Failure Costs

• Scrap costs– costs of poor-quality products

that must be discarded, including labor, material, and indirect costs

• Rework costs– costs of fixing defective

products to conform to quality specifications

• Process failure costs– costs of determining why

production process is producing poor-quality products

• Process downtime costs– costs of shutting down productive process to fix problem

• Price-downgrading costs– costs of discounting poor-quality products—that is, selling products as

“seconds”


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External Failure Costs

• Customer complaint costs– costs of investigating and

satisfactorily responding to a customer complaint resulting from a poor-quality product

• Product return costs– costs of handling and replacing

poor-quality products returned by customer

• Warranty claims costs– costs of complying with product

warranties

• Product liability costs– litigation costs resulting

from product liability and customer injury

• Lost sales costs– costs incurred because

customers are dissatisfied with poor quality products and do not make additional purchases


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Quality–Cost Relationship

• Cost of quality– Difference between price of nonconformance

and conformance– Cost of doing things wrong

• 20 to 35% of revenues– Cost of doing things right

• 3 to 4% of revenues– Profitability

• In the long run, quality is free


Quality Management and Productivity

• Productivity– ratio of output to input

• Yield: a measure of productivity

Yield=(total input)(% good units) + (total input)(1-%good units)(% reworked)

or

Y=(I)(%G)+(I)(1-%G)(%R)


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Product Cost

YRKIK rd ))(())((

Product Cost

where:Kd = direct manufacturing cost per unitI = inputKr = rework cost per unitR = reworked unitsY = yield


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Computing ProductYield for Multistage Processes

Y = (I)(%g1)(%g2) … (%gn)

where:I = input of items to the production process that will result in finished productsgi = good-quality, work-in-process products at stage i


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Quality–Productivity Ratio

QPR– productivity index that includes productivity and

quality costs

QPR =(non-defective units)

(input) (processing cost) + (defective units) (reworked cost)


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Seven Quality Control Tools

• Pareto Analysis• Flow Chart• Check Sheet• Histogram

• Scatter Diagram• SPC Chart• Cause-and-Effect

Diagram


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NUMBER OFCAUSE DEFECTS PERCENTAGE

Poor design 80 64 %Wrong part dimensions 16 13Defective parts 12 10Incorrect machine calibration 7 6Operator errors 4 3Defective material 3 2Surface abrasions 3 2

125 100 %

Pareto Analysis


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Perc

ent f

rom

eac

h ca

use

Causes of poor quality

Machine c

alibrati

ons

Defecti

ve part

s

Wro

ng dim

ensions

Poor Desig

n

Operator e

rrors

Defecti

ve m

ateria

ls

Surfa

ce ab

rasions

0

10

20

30

40

50

60

70(64)

(13)(10)

(6)(3) (2) (2)

Pareto Chart


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Flow Chart

Operation DecisionStart/ Finish

Start/ Finish

Operation

OperationOperation

Operation

Decision


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Check Sheet

COMPONENTS REPLACED BY LABTIME PERIOD: 22 Feb to 27 Feb 2002REPAIR TECHNICIAN: Bob

TV SET MODEL 1013

Integrated Circuits ||||Capacitors |||| |||| |||| |||| |||| ||Resistors ||Transformers ||||CommandsCRT |


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Histogram

0

5

10

15

20

1 2 6 13 10 16 19 17 12 16 2017 13 5 6 2 1


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Scatter DiagramY

X


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Control Chart

18

12

6

3

9

15

21

24

2 4 6 8 10 12 14 16

Sample number

Num

ber o

f def

ects

UCL = 23.35

LCL = 1.99

c = 12.67


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Cause-and-Effect Diagram

QualityProblem

Out of adjustment

Tooling problems

Old / worn

MachinesFaulty testing equipment

Incorrect specifications

Improper methods

Measurement

Poor supervision

Lack of concentration

Inadequate training

Human

Deficienciesin product design

Ineffective qualitymanagement

Poor process design

Process

Inaccuratetemperature control

Dust and Dirt

Environment

Defective from vendor

Not to specifications

Material-handling problems

Materials

Benefits of Quality ControlI. Minimum scrap or rework due to reduced defectives.II. Reduced cost of labour and material as a result of reduced

defectives.III. Uniform quality and reliability of product help in increasing

sales turn over.IV. Reduced variability resulting in-higher quality and reduced

production bottle necks.V. Reduced inspection and reduced inspection costs.VI. Reduced customer complaints.VII. Increased quality consciousness among employees.

VIII.Higher operating efficiency.XI. Better utilisation of resources.X. Better customer satisfaction and employee satisfaction

• Quality Assurance: Activity of providing adequate confidence that a product or service will satisfy given requirement for quality.

Ensuring QualityA. Control of Engineering QualityB. Control of Purchased Material QualityC. Control of Manufacturing Quality D. Actions Supporting the Product After Delivery

Statistical Quality Control (SQC)

• Statistical Quality Control: Application of statistical techniques to accept or reject products already produced or to control the process while it is being carried out.

• Statistical Process Control (SPC): Statistical evaluation of the output of a process during production.

Acceptance Sampling• Acceptance Sampling: A statistical technique

used to take a decision regarding acceptance or rejection of a lot without having to examine the entire lot.

Types of Control ChartsControl charts for variables.Control charts for attributes.

• Control Chart: A graphic comparison of process performance and data with control limits drawn as limit lines on a chart. Helps to determine whether the on-going process is under statistical control or not.

Acceptance Sampling Technique• Acceptance sampling inspection can be either sampling by

attributes or sampling by variables. Accepting sample inspection can be either sampling attributes or sampling by variables.

• Acceptance sampling plans have two important concepts as background when the characteristic being measured are attributes. They are.

A. Average outgoing quality curvesB. operating characteristic curves. Which are described below.

An Average Outgoing Quality (AOQ) Curve

Operating Characteristic (OC) Curve• An operating characteristics curve shows how well an

acceptance sampling plan discriminates between good and bad lots.

Operating Characteristic Curve

Types of Acceptance Sampling Plans

Three types of acceptance sampling plans are:• Single sampling• Double sampling • Sequential sampling

Total Quality ManagementNew Thinking About QualityOld Quality is “small q” New Quality is “Big Q”• About products About organisations• Technical Strategic• For inspectors For everyone• Led by experts Led by Management• High grade The appropriate grade• About control About improvement

Customer–Driven Definitions of Quality

1. Conformance to specifications (requirements).+2. Value for money3. Fitness for use.4. Support provided by seller (customer services)5. Psychological impression (image, aesthetics)

Three Levels of Quality

1. Organisation level – Meeting external customer requirements

2. .Process level – Meeting the needs of internal customers

3. Performer level (job level – Meeting the requirements of or task design level) accuracy, completeness innovation,

timeliness and cost.

Nowadays Total Quality Management (TQM) means1. Top Management Commitment to quality2. Customer involvement and focus3. Employee involvement and focus4. Leadership and strategic planning for quality5. Company-wide quality culture6. Continuous improvement7. Customer satisfaction and delight

What is Quality Control?

1. Setting quality standards (objectives or targets)2. Appraisal of conformance (quality

measurement)3. Taking corrective actions to reduce deviations4. Planning for quality improvement

Principles of Total Quality1. Focus on the customer (Both internal & external2. Participation and Team work3. Employee involvement and empowerment4. Continuous improvement and learning.

What is Total Quality Management (TQM)?

A philosophy that involves everyone in an organisation in a continual effort to improve quality and achieve customer satisfaction.

Six Basic Concepts in TQM• Top management commitment and support.• Focus on both internal and external customers.• Employee involvement and empowerment.• Continuous improvement (KAIZEN)• Partnership with suppliers • Establishing performance measures for processes.

Scope of TQM

1. Are integrated organisational infrastructure2. A set of management practices3. A wide variety of tools and techniques

Modern Quality Management1. Quality Gurus and their PhilosophiesW. Edwards Deming (USA) [U.S. statistician &

consultant known as father of quality control]Deming’s 14 Points for Quality ManagementDeming’s Seven Deadly Diseases and Sins

Deming’s Triangle (3 Axioms)

Deming Wheel/Deming Cycle/P–D–C–A Cycle

2. Joseph Juran (USA) Defined quality as “fitness for use”.a. Top management commitmentb. Costs of qualityc. Quality triology d. 10 steps for quality improvement e. Universal breakthrough sequence.

Costs of Quality1. Prevention costs2. Appraisal cost3. Internal failure costs4. External failure costs Quality Triologyi. Quality planningii. Quality control andiii. Quality improvement

Quality Habit

Philip B Crosby (USA): (Management consultant and director of Crosby’s Quality College. Wrote a book titled “Quality is free” of which 1 million copies sold)

Quality Philosophiesi. Quality is freeii. Goal of zero defects iii.6 ‘C’s – Comprehension, Commitment, Competence,

Correction, Communication, Continuance.iv. Four absolutes of Qualityv. 14 steps for quality improvement vi. Quality Vaccine/Crosby Triangle.

Armand V. Feigenbaum (USA)a. Concept of TQC (Total Quality Control)b. Quality at the sourcec. Three steps to quality – Quality leadership, Modern

quality technology, Organisational Commitment.d. SQC and CWQC (Company-Wide Quality Control)

Kaoru Ishikawa (Japan) (Japanese Quality Authority– Quality circles– Ishikawa diagram for problem solving– Quality training– Root cause elimination– Total employee involvement– Customer focus – Elimination of inspection– C.W.Q.C.– Japanese quality strategy.

Genichi Taguchi (Japan)– Quality Engineering – Taguchi Methods – Taguchi’s quality loss function (L = cd2) [L=Loss–C =

Constant d = deviation i.e., x – T]

Masaki Imai (Management Consultant of Japan) – (Continuous improvement)

Shigeo Shingo (Japan)“Poka Yoke” – means “Fail proofing” or “Fool-proofing” to reduce defects to zero (Handle errors as they occur)

Dr. Walter Shewhart (USA) : (Statistician at Bell Laboratories)Statistical Quality Control : (a) SPC control charts (b) Acceptance sampling (with Dodge & Romig)

Total Quality Management Program

1. Top management commitment and involvement2. Customer involvement3. Designing products for quality4. Designing and controlling production processes 5. Developing supplier partnerships6. Customer service, distribution, installation7. Building teams of empowered employees8. Benchmarking and continuous improvement (Kaizen)

Process ManagementProcess management involves design, control and

improvement of key business process.4 category of business processes are:1. Design processes – product design (or service

design) and design of production/delivery processes that create and deliver products

2. Process design (conversion processes)3. Support processes (purchase, stores, quality control,

marketing, maintenance, finance etc)4. Supplier processes/partnering process (vendor

development)

5 W 2 H Approach to Process Improvement

1. What is being done? 2. Why is this necessary?3. Where is it being done? 4. When is it done?5. Who is doing it? 6. How is it being done?7. How much does it cost now?

Process Improvement Methods

1. Work simplification2. Planned methods changeKaizen enhances quality through:3. Improvement in supplier relations4. New product planning and development5. Improvement in employee safety6. Reduction in cost7. Meeting delivery schedules8. Employer skill development

Activities Falling Under Kaizen Umbrella1. Customer orientation 2. Total quality control 3. Robotics 4. Advanced technology (NC, CNC machines) 5. Quality circles Automation 6. Automation Discipline in workforce 7. Discipline in workforce8. Total productive maintenance 9. Kanban (JIT) 10. Quality improvement 11. Zero defect program 12. Quality improvement teams 13. Co-operation (labour – management relation) 14. New product development15. Productivity improvement

Benchmarking Bench marketing : Measuring a company’s

performance against that of best-in-class companies, determining how the best-in-class achieve those performance levels and using the information as a basis for the company’s targets, strategies and implementation.

3 Types of Benchmarking1. Performance benchmarking2. Process benchmarking3. Strategic benchmarking

Business Process Reengineering (BPR)

Business Process Reengineering: The fundamental rethinking and radical redesign of business processes to achieve dramatic improvements in critical contemporary measures of performance such as cost, quality, service and speed.

Kaizen• Kaizen Japanese word for “ improvement" or "change for the

best", refers to philosophy or practices that focus upon continuous improvement of processes in manufacturing, engineering, and business management.

• When used in the business sense and applied to the workplace, kaizen refers to activities that continually improve all functions, and involves all employees from the CEO to the assembly line workers.

• It also applies to processes, such as purchasing and logistics, that cross organizational boundaries into the supply chain.

• It has been applied in healthcare, psychotherapy, life-coaching, government, banking, and other industries.

• The Toyota Production System is known for kaizen, where all line personnel are expected to stop their moving production line in case of any abnormality and, along with their supervisor, suggest an improvement to resolve the abnormality which may initiate a kaizen.

• The cycle of kaizen activity can be defined as: PDCA• There are five primary 5 “S” phases: They are known as • Sort, • Systematize,• Sweep, • Standardize, • Self-Discipline

1.Seiri<Sort>

• Remove unnecessary items and dispose them properly .

• Make work easy by eliminating obstacles .• Provide no chance of being disturbed with

unnecessary items .• Prevent accumulation of unnecessary items.

2.Seiton<Systematize>

• Arrange necessary items in good order so that they can be easily picked for use .

• Prevent loss and waste of time .• Easy to find and pick up necessary items .• Ensure first-come-first-serve basis .• Make work flow smooth and easy

3.Seiso<Sweep>

• Clean your work place completely .• Easy to check abnormality .• Prevent machinery and equipment

deterioration .• Keep workplace safe and easy to work

4.Seiketsu<Standardize>

• Maintain high standards of house keeping and workplace organization at all times .

• Maintain cleanliness and orderliness

5.Shitsuke<Self-Discipline>

• Do things spontaneously without being told or ordered.

• Standardize good practice.

Kaizen Movement or Japanese 5 ‘S’ Approach

1. Seiri – Straighten-up – Avoid unnecessary materials, tools, machinery, documents etc.

2. Seiton – putting things in order – Everything should be in its place and there should be place for everything (good house keeping)

3. Seiso – clean-up – Every individual should clean-up his work place everyday after the work.

4. Seiketsu – (Personal cleanliness) – Healthy body – healthy mind.

5. Shitsuke (discipline) – Every worker & manager has to follow rules and procedures in the work place.

3 ‘MU’s Check List (of Kaizen)

1. Muda (Waste)2. Muri (Strain)3. Mura (Discrepancy)

Quality Circles (QC)

Quality circle: A small group of employees who meet regularly to undertake work-related projects designed to improve working conditions, spur mutual self-development and to advance the company, all by using quality control concepts.

Quality Standards

Quality Certification Quality Systems• A quality system is defined as "The collective plans,

activities and events that are provided to ensure that a product, process or service will satisfy given needs".

ISO 9000

ISO 9000: A set of international standards on quality management and quality assurance, critical to international business

ISO 14000: A set of international standards for assessing a company’s environmental performance.

ISO 9001 : 2000 The Indian standard (second revision) which is identical with

ISO 9001 : 2000 "Quality Management Systems – Requirements" issued by International organisation for standardisation (ISO) was adopted by the Bureau of Indian Standards (BIS) on the recommendation of the Quality Management Sectional Committee and approval of the Management and Systems Division Council.

Process Approach ISO 9001 : 2000 promotes the adoption of a process approach

when developing, implementing and improving the effectiveness of a quality management system, to enhance customer satisfaction by meeting customer requirements.


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ISO 9000

• A set of procedures and policies for international quality certification of suppliers

• Standards– ISO 9000:2000

• Quality Management Systems—Fundamentals and Vocabulary

• defines fundamental terms and definitions used in ISO 9000 family

• ISO 9001:2000– Quality Management Systems—

Requirements– standard to assess ability to

achieve customer satisfaction• ISO 9004:2000

– Quality Management Systems—Guidelines for Performance Improvements

– guidance to a company for continual improvement of its quality-management system


Implications of ISO 9000 for U.S. Companies

• Many overseas companies will not do business with a supplier unless it has ISO 9000 certification

• ISO 9000 accreditation• ISO registrars• A total commitment to quality

is required throughout an organization

• Encapsulation of best practice- avoids repetition of past mistakes.

• They are a framework for quality assurance processes - they involve checking compliance to standards.

• They provide continuity - new staff can understand the organisation by understanding the standards that are used.

Importance of standards

Product and process standards

Product standards Process standards

Design review form Design review conduct

Requirements document structure Submission of documents to CM

Method header format Version release process

Java programming style Project plan approval process

Project plan format Change control process

Change request form Test recording process

Problems with standards

• They may not be seen as relevant and up-to-date by software engineers.

• They often involve too much bureaucratic form filling.

• If they are unsupported by software tools, tedious manual work is often involved to maintain the documentation associated with the standards.

• Involve practitioners in development. Engineers should understand the rationale underlying a standard.

• Review standards and their usage regularly. Standards can quickly become outdated and this reduces their credibility amongst practitioners.

• Detailed standards should have associated tool support. Excessive clerical work is the most significant complaint against standards.

Standards development

ISO 9000

• An international set of standards for quality management.

• Applicable to a range of organisations from manufacturing to service industries.

• ISO 9001 applicable to organisations which design, develop and maintain products.

• ISO 9001 is a generic model of the quality process that must be instantiated for each organisation using the standard.

ISO 9001

Management responsibility Quality system

Control of non-conforming products Design control

Handling, storage, packaging anddelivery

Purchasing

Purchaser-supplied products Product identification and traceability

Process control Inspection and testing

Inspection and test equipment Inspection and test status

Contract review Corrective action

Document control Quality records

Internal quality audits Training

Servicing Statistical techniques

ISO 9000 certification

• Quality standards and procedures should be documented in an organisational quality manual.

• An external body may certify that an organisation’s quality manual conforms to ISO 9000 standards.

• Some customers require suppliers to be ISO 9000 certified although the need for flexibility here is increasingly recognised.

ISO 9000 and quality management

Project 1quality plan



Project qualitymanagement

Organisationquality manual

ISO 9000quality models

Organisationquality process

is used to develop instantiated as

instantiated as

documents

Supports

Documentation standards• Particularly important - documents are the tangible

manifestation of the software.• Documentation process standards

– Concerned with how documents should be developed, validated and maintained.

• Document standards– Concerned with document contents, structure, and appearance.

• Document interchange standards– Concerned with the compatibility of electronic documents.

Documentation process

Createinitial draft

Reviewdraft

Incorporatereview

commentsRe-draft

document

Proofreadtext

Producefinal draft

Checkfinal draft

Layouttext

Reviewlayout

Produceprint masters

Printcopies

Stage 1:Creation

Stage 2:Polishing

Stage 3:Production

Approved document

Approved document

Chase et. al .

Quality management

•

Tata McGrawCH

APT

ER 9

Six

-Sig

ma

Qua

lity

Chapter 9

Six-Sigma Quality

• Total Quality Management Defined• Quality Specifications and Costs• Six Sigma Quality and Tools• External Benchmarking• ISO 9000• Service Quality Measurement

OBJECTIVES

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Total Quality Management (TQM)

• Total quality management is defined as managing the entire organization so that it excels on all dimensions of products and services that are important to the customer

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Quality Specifications

• Design quality: Inherent value of the product in the marketplace

– Dimensions include: Performance, Features, Reliability/Durability, Serviceability, Aesthetics, and Perceived Quality.

• Conformance quality: Degree to which the product or service design specifications are met

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Costs of Quality

External Failure Costs

Appraisal Costs

Prevention Costs

Internal FailureCosts

Costs ofQuality

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Six Sigma Quality

• A philosophy and set of methods companies use to eliminate defects in their products and processes

• Seeks to reduce variation in the processes that lead to product defects

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Six Sigma Quality (Continued)

• Six Sigma allows managers to readily describe process performance using a common metric: Defects Per Million Opportunities (DPMO)

1,000,000 x

units of No. x unit

per error for iesopportunit ofNumber

defects ofNumber

DPMO

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Six Sigma Quality (Continued)

Example of Defects Per Million Opportunities (DPMO) calculation. Suppose we observe 200 letters delivered incorrectly to the wrong addresses in a small city during a single day when a total of 200,000 letters were delivered. What is the DPMO in this situation?

000,1 1,000,000 x

200,000 x 1

200DPMO

So, for every one million letters delivered this city’s postal managers can expect to have 1,000 letters incorrectly sent to the wrong address.

Cost of Quality: What might that DPMO mean in terms of over-time employment to correct the errors?

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Six Sigma Quality: DMAIC Cycle

• Define, Measure, Analyze, Improve, and Control (DMAIC)

• Developed by General Electric as a means of focusing effort on quality using a methodological approach

• Overall focus of the methodology is to understand and achieve what the customer wants

• A 6-sigma program seeks to reduce the variation in the processes that lead to these defects

• DMAIC consists of five steps….

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Six Sigma Quality: DMAIC Cycle (Continued)

1. Define (D)

2. Measure (M)

3. Analyze (A)

4. Improve (I)

5. Control (C)

Customers and their priorities

Process and its performance

Causes of defects

Remove causes of defects

Maintain quality

9-119

Example to illustrate the process…• We are the maker of this cereal.

Consumer reports has just published an article that shows that we frequently have less than 16 ounces of cereal in a box.

• What should we do?

9-120

Step 1 - Define

• What is the critical-to-quality characteristic?

• The CTQ (critical-to-quality) characteristic in this case is the weight of the cereal in the box.

9-121

2 - Measure

• How would we measure to evaluate the extent of the problem?

• What are acceptable limits on this measure?

9-122

2 – Measure (continued)

• Let’s assume that the government says that we must be within ± 5 percent of the weight advertised on the box.

• Upper Tolerance Limit = 16 + .05(16) = 16.8 ounces

• Lower Tolerance Limit = 16 – .05(16) = 15.2 ounces

9-123

2 – Measure (continued)

• We go out and buy 1,000 boxes of cereal and find that they weight an average of 15.875 ounces with a standard deviation of .529 ounces.

• What percentage of boxes are outside the tolerance limits?

9-124

Upper Tolerance = 16.8

Lower Tolerance = 15.2

ProcessMean = 15.875Std. Dev. = .529

What percentage of boxes are defective (i.e. less than 15.2 oz)?

Z = (x – Mean)/Std. Dev. = (15.2 – 15.875)/.529 = -1.276

NORMSDIST(Z) = NORMSDIST(-1.276) = .100978

Approximately, 10 percent of the boxes have less than 15.2 Ounces of cereal in them!

9-125

Step 3 - Analyze - How can we improve the

capability of our cereal box filling process?

–Decrease Variation–Center Process–Increase Specifications

9-126

Step 4 – Improve – How good is good

enough? Motorola’s “Six Sigma”– 6s minimum from process

center to nearest spec

1 23 1 02 3

12s

6s

9-127

Motorola’s “Six Sigma”

• Implies 2 ppB “bad” with no process shift.

• With 1.5s shift in either direction from center (process will move), implies 3.4 ppm “bad”.

1 23 1 02 3

12s

9-128

Step 5 – Control• Statistical Process Control

(SPC)– Use data from the actual

process– Estimate distributions– Look at capability - is good

quality possible– Statistically monitor the

process over time

9-129

Analytical Tools for Six Sigma and Continuous Improvement: Flow

Chart No, Continue…

Material Received from Supplier Inspect

Material for Defects

Defects found?

Return to Supplier for Credit

Yes

Can be used to find quality problems

9-130

Analytical Tools for Six Sigma and Continuous Improvement: Run Chart

Can be used to identify when equipment or processes are not behaving according to specifications

0.440.460.48

0.50.520.540.560.58

1 2 3 4 5 6 7 8 9 10 11 12Time (Hours)

Diam

eter

9-131

Analytical Tools for Six Sigma and Continuous Improvement: Pareto Analysis

Can be used to find when 80% of the problems may be attributed to 20% of thecauses

Assy.Instruct.

Freq

uenc

y

Design Purch. Training

80%

9-132

Analytical Tools for Six Sigma and Continuous Improvement: Checksheet

Billing Errors

Wrong Account

Wrong Amount

A/R Errors

Wrong Account

Wrong Amount

Monday

Can be used to keep track of defects or used to make sure people collect data in a correct manner

9-133

Analytical Tools for Six Sigma and Continuous Improvement: Histogram

Num

ber o

f Lot

s

Data RangesDefectsin lot

0 1 2 3 4

Can be used to identify the frequency of quality defect occurrence and display quality performance

9-134

Analytical Tools for Six Sigma and Continuous Improvement: Cause & Effect Diagram

Effect

ManMachine

MaterialMethod

Environment

Possible causes: The results or effect

Can be used to systematically track backwards to find a possible cause of a quality problem (or effect)

9-135

Analytical Tools for Six Sigma and Continuous Improvement: Control Charts

Can be used to monitor ongoing production process quality and quality conformance to stated standards of quality

970

980

990

1000

1010

1020

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

LCL

UCL

9-136

Other Six Sigma Tools

• Failure Mode and Effect Analysis (DMEA) is a structured approach to identify, estimate, prioritize, and evaluate risk of possible failures at each stage in the process

• Design of Experiments (DOE) a statistical test to determine cause-and-effect relationships between process variables and output

9-137

Six Sigma Roles and Responsibilities

1. Executive leaders must champion the process of improvement

2. Corporation-wide training in Six Sigma concepts and tools

3. Setting stretch objectives for improvement

4. Continuous reinforcement and rewards

9-138

The Shingo System: Fail-Safe Design

• Shingo’s argument:– SQC methods do not prevent defects– Defects arise when people make errors– Defects can be prevented by providing

workers with feedback on errors

• Poka-Yoke includes:– Checklists– Special tooling that prevents workers from

making errors

9-139

ISO 9000 and ISO 14000

• Series of standards agreed upon by the International Organization for Standardization (ISO)

• Adopted in 1987

• More than 160 countries

• A prerequisite for global competition?

• ISO 9000 an international reference for quality, ISO 14000 is primarily concerned with environmental management

9-140

Three Forms of ISO Certification

1. First party: A firm audits itself against ISO 9000 standards

2. Second party: A customer audits its supplier

3. Third party: A "qualified" national or international standards or certifying agency serves as auditor

9-141

External Benchmarking Steps

1. Identify those processes needing improvement

2. Identify a firm that is the world leader in performing the process

3. Contact the managers of that company and make a personal visit to interview managers and workers

4. Analyze data

9-142

Question Bowl

Approximately what percentage of every sales dollar is allocated to the “cost of quality”?

a. Less than 5%b. About 10%c. Between 15 and 20 %d. More than 30%e. None of the above

Answer: c. Between 15 and 20 % (for cost of reworking, scrapping, repeated service, etc.)

9-143

Question Bowl

Which of the following are classifications of the “cost of quality”?

a. Appraisal costsb. Prevention costsc. Internal failure costsd. External failure costse. All of the above

Answer: e. All of the above

9-144

Question Bowl

Which of the following are functions of a quality control department?

a. Testing product designs for reliabilityb. Gathering product performance datac. Planning and budgeting the QC

programd. All of the abovee. None of the above

Answer: d. All of the above

9-145

Question Bowl

Which of the following is a Critical Customer Requirement (CCR) in the context of a Six Sigma program?

a. DMAICb. DPMOc. PCDAd. DOEe. None of the above

Answer: e. None of the above (The CCR is the criteria that is used to define desired quality. Processing a loan in 10 days is an example of a CCR.)

9-146

Question Bowl

The DMAIC cycle of Six Sigma is similar to which of the following quality management topics?

a. Continuous improvementb. Servqualc. ISO 9000d. External benchmarking e. None of the above

Answer: a. Continuous improvement

9-147

Question Bowl

The “A” in DMAIC stands for which of the following?

a. Alwaysb. Accessibilityc. Analyzed. Acte. None of the above

Answer: d. Analyze (Define, Measure, Analyze, Improve and Control)

9-148

Question Bowl

Which of the following analytical tools depict trends in quality data over time?

a. Flowchartsb. Run chartsc. Pareto chartsd. Checksheetse. Cause and effect diagrams

Answer: b. Run charts

9-149

End of Chapter 9

9-150

•

Tata McGrawCHAP

TER

9A

Proc

ess C

apab

ility

and

SPC

Chapter 9A

Process Capability and SPC

• Process Variation• Process Capability• Process Control Procedures

– Variable data– Attribute data

• Acceptance Sampling– Operating Characteristic Curve

OBJECTIVES

9A-153

Basic Forms of Variation

Assignable variation is caused by factors that can be clearly identified and possibly managed

Common variation is inherent in the production process

Example: A poorly trained employee that creates variation in finished product output.

Example: A molding process that always leaves “burrs” or flaws on a molded item.

9A-154

Taguchi’s View of Variation

IncrementalCost of Variability

High

Zero

LowerSpec

TargetSpec

UpperSpec

Traditional View

IncrementalCost of Variability

High

Zero

LowerSpec

TargetSpec

UpperSpec

Taguchi’s View

Traditional view is that quality within the LS and US is good and that the cost of quality outside this range is constant, where Taguchi views costs as increasing as variability increases, so seek to achieve zero defects and that will truly minimize quality costs.

9A-155

Process Capability Index, Cpk

ss 3

X-UTLor 3

LTLXmin=C pk

Shifts in Process Mean

Capability Index shows how well parts being produced fit into design limit specifications.

As a production process produces items small shifts in equipment or systems can cause differences in production performance from differing samples.

9A-156

A simple ratio: Specification Width

_________________________________________________________

Actual “Process Width”

Generally, the bigger the better.

Process Capability – A Standard Measure of How Good a Process Is.

9A-157

Process Capability

This is a “one-sided” Capability IndexConcentration on the side which is closest to the

specification - closest to being “bad”

ss 3

;3

XUTLLTLXMinC pk

9A-158

The Cereal Box Example

• We are the maker of this cereal. Consumer reports has just published an article that shows that we frequently have less than 16 ounces of cereal in a box.

• Let’s assume that the government says that we must be within ± 5 percent of the weight advertised on the box.

• Upper Tolerance Limit = 16 + .05(16) = 16.8 ounces• Lower Tolerance Limit = 16 – .05(16) = 15.2 ounces• We go out and buy 1,000 boxes of cereal and find that they weight

an average of 15.875 ounces with a standard deviation of .529 ounces.

9A-159

Cereal Box Process Capability

• Specification or Tolerance Limits– Upper Spec = 16.8 oz– Lower Spec = 15.2 oz

• Observed Weight– Mean = 15.875 oz– Std Dev = .529 oz

ss 3

;3

XUTLLTLXMinC pk

)529(.3875.158.16;

)529(.32.15875.15MinC pk

5829.;4253.MinC pk

4253.pkC

9A-160

What does a Cpk of .4253 mean?

• An index that shows how well the units being produced fit within the specification limits.

• This is a process that will produce a relatively high number of defects.

• Many companies look for a Cpk of 1.3 or better… 6-Sigma company wants 2.0!

9A-161

Types of Statistical Sampling

• Attribute (Go or no-go information)– Defectives refers to the acceptability of

product across a range of characteristics.– Defects refers to the number of defects

per unit which may be higher than the number of defectives.

– p-chart application

• Variable (Continuous)– Usually measured by the mean and the

standard deviation.– X-bar and R chart applications

9A-162

Statistical Process Control (SPC) Charts

UCL

LCL

Samples over time

1 2 3 4 5 6

UCL

LCL

Samples over time

1 2 3 4 5 6

UCL

LCL

Samples over time

1 2 3 4 5 6

Normal Behavior

Possible problem, investigate

Possible problem, investigate

9A-163

Control Limits are based on the Normal Curve

x

0 1 2 3-3 -2 -1z

m

Standard deviation units or “z” units.

9A-164

Control Limits

We establish the Upper Control Limits (UCL) and the Lower Control Limits (LCL) with plus or minus 3 standard deviations from some x-bar or mean value. Based on this we can expect 99.7% of our sample observations to fall within these limits.

xLCL UCL

99.7%

9A-165

Example of Constructing a p-Chart: Required Data

1 100 42 100 23 100 54 100 35 100 66 100 47 100 38 100 79 100 1

10 100 211 100 312 100 213 100 214 100 815 100 3

Sample

No.

No. of

Samples

Number of defects found in each sample

9A-166

Statistical Process Control Formulas:Attribute Measurements (p-Chart)

p =Total Number of Defectives

Total Number of Observations

ns )p-(1 p = p

p

p

z - p = LCL

z + p = UCL

s

s

Given:

Compute control limits:

9A-167

1. Calculate the sample proportions, p (these are what can be plotted on the p-chart) for each sample

Sample n Defectives p1 100 4 0.042 100 2 0.023 100 5 0.054 100 3 0.035 100 6 0.066 100 4 0.047 100 3 0.038 100 7 0.079 100 1 0.01

10 100 2 0.0211 100 3 0.0312 100 2 0.0213 100 2 0.0214 100 8 0.0815 100 3 0.03

Example of Constructing a p-chart: Step 1

9A-168

2. Calculate the average of the sample proportions

0.036=1500

55 = p

3. Calculate the standard deviation of the sample proportion

.0188= 100

.036)-.036(1=)p-(1 p = p ns

Example of Constructing a p-chart: Steps 2&3

9A-169

4. Calculate the control limits

3(.0188) .036

UCL = 0.0924LCL = -0.0204 (or 0)

p

p

z - p = LCL

z + p = UCL

s

s

Example of Constructing a p-chart: Step 4

9A-170

Example of Constructing a p-Chart: Step 5

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

p

Observation

UCL

LCL

5. Plot the individual sample proportions, the average of the proportions, and the control limits

9A-171

Example of x-bar and R Charts: Required Data

Sample Obs 1 Obs 2 Obs 3 Obs 4 Obs 51 10.68 10.689 10.776 10.798 10.7142 10.79 10.86 10.601 10.746 10.7793 10.78 10.667 10.838 10.785 10.7234 10.59 10.727 10.812 10.775 10.735 10.69 10.708 10.79 10.758 10.6716 10.75 10.714 10.738 10.719 10.6067 10.79 10.713 10.689 10.877 10.6038 10.74 10.779 10.11 10.737 10.759 10.77 10.773 10.641 10.644 10.72510 10.72 10.671 10.708 10.85 10.71211 10.79 10.821 10.764 10.658 10.70812 10.62 10.802 10.818 10.872 10.72713 10.66 10.822 10.893 10.544 10.7514 10.81 10.749 10.859 10.801 10.70115 10.66 10.681 10.644 10.747 10.728

9A-172

Example of x-bar and R charts: Step 1. Calculate sample means, sample ranges, mean of means, and mean of ranges.

Sample Obs 1 Obs 2 Obs 3 Obs 4 Obs 5 Avg1 10.68 10.689 10.776 10.798 10.714 10.7322 10.79 10.86 10.601 10.746 10.779 10.7553 10.78 10.667 10.838 10.785 10.723 10.7594 10.59 10.727 10.812 10.775 10.73 10.7275 10.69 10.708 10.79 10.758 10.671 10.7246 10.75 10.714 10.738 10.719 10.606 10.7057 10.79 10.713 10.689 10.877 10.603 10.7358 10.74 10.779 10.11 10.737 10.75 10.6249 10.77 10.773 10.641 10.644 10.725 10.71010 10.72 10.671 10.708 10.85 10.712 10.73211 10.79 10.821 10.764 10.658 10.708 10.74812 10.62 10.802 10.818 10.872 10.727 10.76813 10.66 10.822 10.893 10.544 10.75 10.73314 10.81 10.749 10.859 10.801 10.701 10.783

9A-173

Example of x-bar and R charts: Step 2. Determine Control Limit Formulas and Necessary Tabled Values

x Chart Control Limits

UCL = x + A R

LCL = x - A R2

2

R Chart Control Limits

UCL = D R

LCL = D R4

3

From Exhibit TN8.7

n A2 D3 D42 1.88 0 3.273 1.02 0 2.574 0.73 0 2.285 0.58 0 2.116 0.48 0 2.007 0.42 0.08 1.928 0.37 0.14 1.869 0.34 0.18 1.82

10 0.31 0.22 1.7811 0.29 0.26 1.74

9A-174

Example of x-bar and R charts: Steps 3&4. Calculate x-bar Chart and Plot Values

10.601

10.856

=).58(0.2204-10.728RA - x = LCL

=).58(0.2204-10.728RA + x = UCL

2

2

10.550

10.600

10.650

10.700

10.750

10.800

10.850

10.900

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Sample

Mea

ns

UCL

LCL

9A-175

Example of x-bar and R charts: Steps 5&6. Calculate R-chart and Plot Values

0

0.46504

)2204.0)(0(R D= LCL

)2204.0)(11.2(R D= UCL

3

4

0.000

0.100

0.200

0.300

0.400

0.500

0.600

0.700

0.800

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Sample

RUCL

LCL

9A-176

Basic Forms of Statistical Sampling for Quality Control

• Acceptance Sampling is sampling to accept or reject the immediate lot of product at hand

• Statistical Process Control is sampling to determine if the process is within acceptable limits

9A-177

Acceptance Sampling

• Purposes– Determine quality level– Ensure quality is within predetermined level

• Advantages– Economy– Less handling damage– Fewer inspectors– Upgrading of the inspection job– Applicability to destructive testing– Entire lot rejection (motivation for improvement)

9A-178

Acceptance Sampling (Continued)

• Disadvantages– Risks of accepting “bad” lots and rejecting

“good” lots– Added planning and documentation– Sample provides less information than 100-

percent inspection

9A-179

Acceptance Sampling: Single Sampling Plan

A simple goal

Determine (1) how many units, n, to sample from a lot, and (2) the maximum number of defective items, c, that can be found in the sample before the lot is rejected

9A-180

Risk

• Acceptable Quality Level (AQL)– Max. acceptable percentage of defectives

defined by producer• The a (Producer’s risk)

– The probability of rejecting a good lot• Lot Tolerance Percent Defective (LTPD)

– Percentage of defectives that defines consumer’s rejection point

• The (Consumer’s risk)– The probability of accepting a bad lot

9A-181

Operating Characteristic Curve

n = 99c = 4

AQL LTPD

00.10.20.30.40.50.60.70.80.9

1

1 2 3 4 5 6 7 8 9 10 11 12

Percent defective

Prob

abili

ty o

f acc

epta

nce

=.10(consumer’s risk)

a = .05 (producer’s risk)

The OCC brings the concepts of producer’s risk, consumer’s risk, sample size, and maximum defects allowed together

The shape or slope of the curve is dependent on a particular combination of the four parameters

9A-182

Example: Acceptance Sampling Problem

Zypercom, a manufacturer of video interfaces, purchases printed wiring boards from an outside vender, Procard. Procard has set an acceptable quality level of 1% and accepts a 5% risk of rejecting lots at or below this level. Zypercom considers lots with 3% defectives to be unacceptable and will assume a 10% risk of accepting a defective lot.

Develop a sampling plan for Zypercom and determine a rule to be followed by the receiving inspection personnel.

9A-183

Example: Step 1. What is given and what is not?

In this problem, AQL is given to be 0.01 and LTDP is given to be 0.03. We are also given an alpha of 0.05 and a beta of 0.10.

What you need to determine is your sampling plan is “c” and “n.”

9A-184

Example: Step 2. Determine “c”

First divide LTPD by AQL.LTPDAQL

= .03.01

= 3

Then find the value for “c” by selecting the value in the TN7.10 “n(AQL)”column that is equal to or just greater than the ratio above.

Exhibit TN 8.10

c LTPD/AQL n AQL c LTPD/AQL n AQL0 44.890 0.052 5 3.549 2.6131 10.946 0.355 6 3.206 3.2862 6.509 0.818 7 2.957 3.9813 4.890 1.366 8 2.768 4.6954 4.057 1.970 9 2.618 5.426

So, c = 6.

9A-185

Question Bowl

A methodology that is used to show how well parts being produced fit into a range specified by design limits is which of the following?

a. Capability indexb. Producer’s riskc. Consumer’s riskd. AQLe. None of the above

Answer: a. Capability index

9A-186

Question Bowl

On a quality control chart if one of the values plotted falls outside a boundary it should signal to the production manager to do which of the following?

a. System is out of control, should be stopped and fixed

b. System is out of control, but can still be operated without any concern

c. System is only out of control if the number of observations falling outside the boundary exceeds statistical expectations

d. System is OK as ise. None of the above

Answer: c. System is only out of control if the number of observations falling outside the boundary exceeds statistical expectations

9A-187

Question Bowl

You want to prepare a p chart and you observe 200 samples with 10 in each, and find 5 defective units. What is the resulting “fraction defective”?

a. 25b. 2.5c. 0.0025d. 0.00025e. Can not be computed on data

above

Answer: c. 0.0025 (5/(2000x10)=0.0025)

9A-188

Question Bowl

You want to prepare an x-bar chart. If the number of observations in a “subgroup” is 10, what is the appropriate “factor” used in the computation of the UCL and LCL?

a. 1.88b. 0.31c. 0.22d. 1.78e. None of the above

Answer: b. 0.31

9A-189

Question Bowl

You want to prepare an R chart. If the number of observations in a “subgroup” is 5, what is the appropriate “factor” used in the computation of the LCL?

a. 0b. 0.88c. 1.88d. 2.11e. None of the aboveAnswer: a. 0

9A-190

Question Bowl

You want to prepare an R chart. If the number of observations in a “subgroup” is 3, what is the appropriate “factor” used in the computation of the UCL?

a. 0.87b. 1.00c. 1.88d. 2.11e. None of the above

Answer: e. None of the above

9A-191

Question Bowl

The maximum number of defectives that can be found in a sample before the lot is rejected is denoted in acceptance sampling as which of the following?

a. Alphab. Betac. AQLd. ce. None of the above

Answer: d. c

9A-192

End of Chapter 9A

9A-193

What is a “Just-in-time System”?

• “Just-in-time”: A philosophy of manufacturing based on planned elimination of all waste and continuous improvement of productivity.

Concepts of JIT

The three fundamental concepts of JIT are :1. Elimination of waste and variability2. “Pull” versus “Push” system and3. Manufacturing cycle time (or “throughput”

time).

Overview of JIT manufacturing

Inventory reduction Quality improvement Lead time reduction Lead time reduction Continuous Improvement Total Preventive Maintenance Strategic Gain

Characteristics of Just-in-Time System

1. Pull method of material flow2. Constantly high quality3. Mall lot sizes4. Uniform workstation loads5. Standardised components and work methods6. Close supplier ties7. Flexible workforce8. Line flow strategy9. Automated production10. Preventive maintenance

JIT Manufacturing Versus JIT Purchasing

JIT manufacturing: An Organisation- wide approach to produce output with in the minimum possible lead time and at the lowest possible total cost by continuously identifying and eliminating all forms of waste and variance.

JIT purchasing: Same pull type approach used in JIT manufacturing applied to purchasing shipments of parts and components from suppliers.

Pre-requisites for JIT Manufacturing

1. Stabilise production schedules.2. Make the factories focussed.3. Increase production characteristics of manufacturing work

centers.4. Improve product quality.5. Cross-train workers so that they are multi-skilled and

competent in several jobs.6. Reduce equipment break downs through preventive

maintenance.7. Develop long-term supplier relationships that avoid

interruptions in material flows.

Elements of JIT Manufacturing System

1. Eliminate waste2. Enforced problem solving3. Continuous improvement4. Involvement of people5. TQM6. Parallel processing

Benefits of JIT System

1. Low inventory levels2. Shorter production cycle time3. Improved product quality4. Reduced WIP Inventory5. Better labour utilisation.

Major Tools and Techniques of JIT Manufacturing

Shop-floor JIT or little JIT has nine tactical tools.The tactical tools of little JIT are :i. Kanban system or Pull schedulingii. Set up reduction (SMED)iii. Lean productioniv. Poka- Yoke (Fool proofing)v. Quality at the source

vi. Standardisation and simplificationvii. Supplier partnershipsviii. Reduced transaction processing andix. Kaizen (continuous improvement).

Kanban system: A physical control system consisting of cards and containers. The system is used to signal the need for more parts and to ensure that those parts are produced in time to support subsequent fabrication or assembly.

Benefits of Kanban

Kanban systems have resulted in significant benefits :1. Reduced inventory level2. Less confusion over sequence of activities3. Less obsolescence of inventories while in storage4. Smaller floor space requirements for storing inventory

The focus of JIT systems is on improving the process, therefore, some of the JIT concepts useful for the manufacturer are also useful to service providers. These concepts include the following :

1. Consistently high quality2. Uniform facility loads3. Standardised work methods4. Close supplier ties5. Flexible workforce 6. Automation7. Preventive maintenance8. Pull method of material flow9. Line flow strategy

Safety Management

Safety management system (SMS)

• (SMS) is a term used to refer to a comprehensive business management system designed to manage safety elements in the workplace.

• A SMS provides a systematic way:• to identify hazards and• control risks • while maintaining assurance that • these risk controls are effective.

SMS can be defined as:• ...a businesslike approach to safety.• It is a systematic, explicit and comprehensive process

for managing safety risks. • As with all management systems, a SMS provides for :• goal setting, • planning, and • measuring performance. • A SMS is woven into the fabric of an organization. • It becomes part of the culture, the way people do their

jobs.

Defining safety

• For the purposes of defining safety management, safety can be defined as:

• ... the reduction of risk to a level that is as low as is reasonably practicable.

Industry

• Chemical industry• Manufacturing plants• Cement manufacturing plant• Textile industry • Diamond industry • Steel plant• Foundry ( Metal Casting Plant)• Power Production plant ( Coal based , nuclear based ,

water based power plant , gas based power plant )

Hazard • A hazard is a situation that poses a level of threat

to life, health, property, or environment. Most hazards are dormant or potential, with only a theoretical risk of harm; however, once a hazard becomes "active", it can create an emergency situation.

• A hazardous situation that has come to pass is called an incident.• Hazard and possibility interact together to create risk.• Identification of hazard risks is the first step in performing a risk

assessment.• One key concept in identifying a hazard is the presence of stored

energy that, when released, can cause damage.

Types of energy

• Heat energy• Mechanical energy • Chemical energy• Electrical energy• High Pressure energy • Energy due to speed

Types of hazards

• Due to Heat – high temperature work area hazards

• Coal ash – dust • Due to Speed – moving fast at work place with

material and without material• Due to machine tool or equipment failure • Fire hazards• Hazard due to Chemical leakage or gas leakage

Risk• Risk can be defined as the likelihood or probability of a

given hazard of a given level causing a particular level of loss of damage (Alexander, Confronting catastrophe, 2000).

• Risk can be equated with a simple equation, although it is not mathematical but artificial equation .

• The total risk according to UNDRO 1982 is the "sum of predictable deaths, injuries, destruction, damage, disruption, and costs of repair and mitigation caused by a disaster of a particular level in a given area or areas.

• Mathematically it can be written as• Total risk = (Sum of the elements at risk) x (hazard x

vulnerability)

Risk, vulnerability and hazard

• This is simplified into an equation:• R (Risk) = H (hazard) x V (vulnerability)• These are the three factors or elements which we are

considering here in this artificial mathematical equation.

• Vulnerability refers to the inability to withstand the effects of a hostile environment.

• A window of vulnerability (WoV) is a time frame within which defensive measures are reduced, compromised or lacking.

Losses

• Health• Life• Material• Time • Machinery• Plant • Ultimately adds costs (waste of money) and

increases idle time .

• There are three imperatives for adopting a safety management system for a business – these are ethical, legal and financial.

• There is an implied moral obligation placed on an employer to ensure that work activities and the place of work to be safe, there are legislative requirements defined in just about every jurisdiction on how this is to be achieved and there is a substantial body of research which shows that effective safety management (which is the reduction of risk in the workplace) can reduce the financial exposure of an organisation by reducing direct and indirect costs associated with accident and incidents.

• To address these three important elements, an effective SMS should:

• Define how the organisation is set up to manage risk.• Identify workplace risk and implement suitable controls.• Implement effective communications across all levels of the

organisation.• Implement a process to identify and correct non-conformities.• Implement a continual improvement process.• A safety management system can be created to fit any

business type and/or industry sector.

Terminologies used in Safety management

Developing a Proactive Safety Program

• 1. Conduct a thorough risk assessment• 2. Reduce Potential Hazards through Design• 3. Consider Machine Guarding• 4. Add Advanced Controls• 5. Promote Awareness• 6. Provide Training• 7. Conduct Follow-up Assessments• 8. Seek Experience and Expertise

quality management

Documents