presentation1 (vpa) tqm

8/8/2019 Presentation1 (VPA) TQM

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Total QualityManagement

Prof. V. P. Arora

Associate Professor


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Definition of Total Quality Management (TQM)Total Quality Management (TQM) is an enhancement tothe traditional way of doing business. It is a proven

technique to guarantee survival in world-classcompetition.Total Made up of the whole.Quality Degree of excellence a product or serviceprovides.

Management Act, art, or manner of handling,controlling, directing etc.


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TQM

Managing the entire organization so that it excels in all

dimensions of products & services that are important tothe customer

Philosophical Element Generic Tools Tools of Q.C Deptt.

Customer Driven quality

Leadership

Continuous improvement

Employee participation & development

Quick response

Design quality & prevention

Management by fact

Partnership development

Corporate responsibility & citizenship

SPC Tools

Process flow charts

Check sheets

Pareto analysis &histogram

Cause & effect (or fish

bone) diagrams

Run charts

Scatter diagrams

Control charts Qualityfunction deployment

SQC Methods

Sampling plans

Process capability

Taguchi Methods


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Elements of Total Quality ManagementSPC = statistical process controlBasic Approach of TQM requires six basic concepts:

1. A committed and involved management to providelong-term, top-to-bottom organizational support.

2. An unwavering focus on the customer, bothinternally and externally.

3. Effective involvement and utilization of the entirework force.

4. Continuous improvement of the business andproduction process.

5. Treating suppliers as partner.

6. Establish performance measures for the processes.These concepts outline an excellent way to run an

organization.


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The Dimensions of Quality

Dimension Meaning and Example

Performance Primary product characteristics, such as the brightnes

of the picture

Features Secondary characteristics, added features, such as

remote control

Conformance Meeting specifications or industry standards,

workmanship

Reliability Consistency of performance over time, average timefor the unit to fail

Durability Useful life, includes repair

Service Resolution of problems and complaints, ease of repair

Response Human-to-human interface, such as the courtesy of

the dealer

Aesthetics sensory characteristics, such as exterior finish

Reputation Past performance and other intangibles, such as being

ranked first


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ISO 9000 SERIESISO 9000 is a series of standards agreed upon by theinternational organization for standardization (ISO) andadopted in 1987.

More than 100 countries now recognize the 9000 seriesfor quality standards and certification for international

trade. In Europe & European common market (ECM)alone, more than 50,000 companies have certified ascomplying with these standards.All companies having international trade will have to

adopt these standards eventually.

THE ISO 9000 SERIESISO 9000 consists of five primary parts numbered

as 9000 through 9004


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ISO

9002

Design

Development Procurement Production Installation Servicing

ISO 9001

ISO9003


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QUALITY SYSTEM ISOGuide line for Use:9000 : Quality management & quality assurancestandards- guidelines for selection & use.9004 : Quality management & quality systemelements guidelinesQuality system9001 : Model for quality assurance in design,

production, installation & servicing.9002 : Model for quality assurance in production &installation.9003 : Model for quality assurance in final inspection

test.ISO certification can take from 3 to 6 months to as longas two years if top management is not fully committed.Certification involves getting the proper documents,initiating the required procedures & practices and

conducting internal audits.


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There are three forms of certification.First Party : A firm audits itself against ISO 9000

standards

Second Party : A customer audits its supplierThird Party : A Qualified national or international

standards or certifying Agencyserves as auditor

The best certification is by a third party and once passed,the firm can be registered & recorded as havingachieved ISO 9000 status.

ISO specifies the way the firm operates as well as its

quality standards, delivery times, service levels & soon. If a manufacturer wants to purchase, he can eithervisit / audit the supplier but it is always easier,cheaper, quicker & legally safer to select certified

supplier


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Benefits from ISO-9000

ISO 9000 certification has become the de-facto minimumrequirement for those wishing to compete globally

All actions in preparing for ISO certification & inmaintaining the certification would result instreamlining of quality management system which may

lead to improvements in product quality.

It can also lead to significant cost reductions throughreduction in rework, warranty work, repair, scrap, etc

ISO 9000 lays stress on customer orientation. This wouldresult in better overall results for the company inaddition to improving customer relations.

There may be an impetus to improve employee relations,

employee empowerment and


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The 20 Elements to be addressed in an ISO 9000Quality System

1.Management Responsibility2.quality system3.contract review4.design control

5.document control6.Purchasing7.Customer-Supply Material8.Product Identification and Traceability9.Process Control

10.Inspection and Testing


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11.Inspection, Measuring, and Test Equipment12.Inspection and Test Status13.Control of Nonconforming Product

14.Corrective Action15.Handling, Storage, Packaging, and Delivery16.Quality Records17.Internal Quality Audits

18.Training19.Servicing20.Statistical Techniques


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Quality Function Deployment (QFD)QFD is a systematic and organized approach of

taking customer needs and demands into considerationwhile designing new products and services or while

improving the existing products and services. Someexperts also call it as customer driven engineeringbecause the voice of the customer is diffused throughoutthe product (or service) development life cycle.

These needs are deployed into design requirementsand subsequently through the manufacturing chain ofcritical part characteristics and key process requirements.Finally, these needs are deployed in operationalspecifications.


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Benefits of QFDThe major benefits of QFD are meeting and exceeding

customer satisfaction and thus obtaining higher marketshare and profits.

1.QFD minimizes the later engineering changes andresults in better quality

2.Customer complaints about and dissatisfaction withnew products decrease with passage of time.

3.QFD applies a cross-functional approach breakingcommunication walls amongst departments of acompany.

4.Develop a deeper understanding of customer needs and

have the customers voice into the business for makingtrade-offs, resulting in superior decisions for theorganization.

5.Streamlining of processes helps in elimination of many

internal processes that do not add value.


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6. QFD helps in evaluating customer needs with respectto competitive products and services.

7.It provides opportunities for introducing new products.8.QFD provides an excellent framework for cross-

functional deployment of quality, cost and delivery.

9.QFD by collecting and analyzing latest information on acontinuous basis allows for quick changes in productdevelopment process.

QFD provides a much needed horizontal weave across the

organization which in turn helps in smooth propagation ofTQM. In the most Indian companies, this horizontalweave is missing in the current traditional managementhierarchy because these organizations are managed

vertically. The shorter product/service development cycleand hi her roductivit are the main merits of FD.


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TQM GURUSA TQM Guru is an expert thinker who communicates histhoughts through verbal and written expressions and thuscontributes to the field of TQM. Starting just after World

War II a number of philosophers and thinkers have madetheir contributions to the movement of Total QualityManagement. In the summer of 1985 the name TotalQuality Management was first suggested by Nancy

Warren, a behavioural scientist in the US Navy,thereafter, a number of TQM Gurus have made theirsignificant contributions. Many of the TQM Gurus areAmericans and a very few of them have their origin inJapan. Some of the major contributors towards thethought of TQM are:


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PHILOSOPHIES OF QUALITY GURUS


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PHILOSOPHIES OF QUALITY GURUSThe customers of today are very different compared toyester years. Today the customer is demanding quality inproduct, in services, in life, in everything. Only those

companies that upgrade to global standards will survive.There are many theories propagated by quality experts.

Demings approach to TQM

Deming is among the pioneers of the TQM concept. Hisviews on improving quality contains fourteen pointsapproach as given below:

1 Ai t ti i t f f i i


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1.Aim at creating consistency of purpose for improvingservices and products

2.Aim at adopting the new philosophy for making theaccepted levels of defects, delays, or mistakes

unwanted.3.Aim to stop reliance on mass inspection as it neither

improves nor guarantees quality (The team workbetween the firm and its supplies is the way for the

process of improvement.)4.Try to stop awarding business with respect to the price.5.Aim to discover problems. Management must work

continually to improve the system6.Aim to take advantage of modern methods used for

training. In developing a training program, take intoconsideration such items as


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7 Ai t i tit t d i i h


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7.Aim to institute modern supervision approaches.8.Aim to eradicate fear so that everyone involved may

work to his or her full capacity.9.Aim to tear down department barriers so that everyone

can work as a team member10.Try to eliminate items such as goals, posters, and

slogans that call for new productivity levels without theimprovement of methods.

11.Aim to make your organization free of work standardsprescribing numeric quotas.

12.Aim to eliminate factors that inhibit employeeworkmanship pride.

13.Aim to establish an effective education and trainingprogram.

14.Establish ways to develop a program that will push theabove 13 points every day for new endingimprovement.

PhilipB Crosby


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PhilipB. CrosbyQuality is free declares Philip Crosby. He continues to believe that

quality means getting it right the first time, rather than merelylaying down acceptable levels of quality. The 14 steps of qualityimprovement declared by Crosby are:

1.Make it clear that management is committed to quality.[Key: management Commitment.]

2.Form quality improvement teams with representativesfrom each department [Key: Quality improvement]

3.Determine where current and potential qualityproblems lie [Key: Quality measurement]

4.Evaluate the cost of quality and explain its use a s amanagement tool. [Key: Cost of Quality]

5.Raise the quality awareness and personal concern of allemployees. [Key: Quality awareness]6.Take actions to correct problems identified through

previous steps [Key: Corrective action]

7 Establish a committee fo the e o defects p og amme


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7.Establish a committee for the zero defects programme.[Key: Zero Defect Planning]

8.Train supervisors to actively carry out their part of thequality improvement programme. [Key: Supervisor

training]9.Hold a zero defects day to let all employees realize

that there has been a change. [Key: ZD day]10.Encourage individuals to establish improvement goals

for themselves and their groups [Key: Goal setting]11.Encourage employees to communicate to management

the obstacles they face in attaining their. [Key: Error-cause removal]

Joseph M Juran


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Joseph M, JuranJuran advocated ten steps to quality improvement1.Start with building awareness of the need and

opportunity for improvement.

2.set realistic goals for improvement3.Organize to reach the goals (by methods to establish a

quality council, identify problems, select Projects,appoint teams, designate facilitators).

4.Emphasis on training5.Solve problems by carrying out projects6.Progress must be reported7.Give recognition to any body who achieves8.Communicate results with all concerned9.Keep score by being quantitative10.Maintain a regular momentum by making annual

improvement part of the systems and processes of thecompany

Evolutionary Phases of Quality Activity Focus


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Phase

Inspection Detection and segregation of defectives

Sampling schemes Economy and efficiency

Quality control Prevention of sub-standard and economic manufacture

SPC Use of statistical concepts

SQC Methods for efficiency and economy

QC Teams Investigation and resolution of quality problems

Quality Assurance Customer satisfaction using systems approach, quality policy,objectives planning and audit jointly in the case oforganized/dominant customers

Vender Quality Assurance Ensuring manufacture and supply of required quality product

Evolutionary Phases of Quality Activity Focus

Quality Engineering Robust products at commensurate cost through product design and process


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y g g p g p g pengineering

TQC Coordination to make all functional groups of an organization to dischargetheir responsibilities towards product quality

Self-control Integration of quality related tasks with the jobs

QC education & training Performance of the job right the first time and every time

CWQC Consumer oriented quality control participation by employees at all levels of improvements

Quality circles and Self-directed Teams Participation of employee teams in improvement of quality, cost,productivity, work life, etc. in their work areas

TQM Continuous improvement all around including environment, work life,quality, cost schedules, etc.

Steering Council Top managers leadership and participation

Policy management/and deployment Regular activities to reflect policies

QFS, Taguchi methods, and Design ofExperiments

Customer delight to add value over and above consumer needs

HRD Enable employees perform their roles well in spite of swift changes takingplace all around-technology, organization, environment, society, etc.

Quality Audits Top management to gain first-hand knowledge of practices


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CONCEPT OF KAIZENImai has brought together various management theories,philosophies and tools that have been popular in Japanover the years, as a single concept, Kaizen. There aremany quality experts, whose principles formed the basisof the Kaizen concept. Kaizen means continuousimprovement involving everybody. The philosophyadvocates on-going improvement, not only in ones

working life, but also in personal life, home life and sociallife. The term Kaizen originates from the Japanese words,Kai that means change, whereas, zen means for thebetter, therefore, it means change for the better. It

signifies constant and gradual improvement, no matterhow small it is. It should be taking place all the time inevery process, involving everyone from all the ranks ofmanagement and the workforce. In brief, the systemincludes:


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Total employee involvement starting from topmanagement;

Empowering people;

Listening to them; Promoting zero investment improvements; and Focus on efforts rather than results in Kaizen

evaluation and performance appraisal.

The four phases ofKaizen are: Motivation management; Human resource development; Improvement; and Institutionalization.

The Kaizen umbrella, as shown in Figure is quitecomprehensive. It is not any one technique rather aphilosophy of continuous quality improvement.


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KAIZEN

Kanban

Quality

improvement

Just in

time

Zero-

Defect

Small Group

Activities

Cooperative

Labour -

Management

Relation

ProductivityImprovement

Customer

orientation

TQM

Robotics

Quality Circles

Suggestion

schemes -

T PM

ISO: 9000 Standards

TPM=Total Preventive Maintenance

COST OF QUALITY


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COST OF QUALITYThe cost of quality (COQ) is defined as the sum of the

costs of everything that would not have beennecessary if everything else was done right the first

time.Types of quality costsThe cost of quality (COQ) can be classified into three

major categories as given below:

1.Cost of conformance,2.Cost of non-conformance,3.Basic operational costs.

Cost of Conformance (COC)


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Cost of Conformance (COC)Cost of conformance (COC) is the cost which anorganization incurs in meeting the requirements of itscustomers. A strong element of this cost is the money

that a company spends on the product for preventing itform going wrong or checking the product right before itreaches the customer.Cost of Non-conformance (CONC)

The cost of non-conformance (CONC) to customerrequirements are the failure costs. These costs areincurred by a company in repairing what has gone wrongduring manufacturing.Basic Operational costs (BOC)The basic operational costs (BOC) are those costs whichan organization cannot avoid encountering during thenormal performance of its business.

H i ht dBasic


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Heightened

Efficiency

Improved Customer

Satisfaction

Lower

Operating Cost

Cost of

Non-

Conformance

(CONC)

Cost of

Conformance

(COC)

Cost of

Qualify

(COQ)

Cost of

Quality

Reduced

Operating

Cost (BOC)

Benefits of Reducing the Cost ofQuality

If all the three categories of costs are systematically reduced, several

benefits can accrue to the company.

ANOTHER METHOD TO MEASURE COST OF QUALITY:


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ANOTHER METHOD TO MEASURE COST OF QUALITY:This analysis is based on following assumptions:

i. That failures are causedii. That prevention is cheaper

iii.That performance can be measured

Four Types of costs:1. Appraisal costsThe costs of inspection, testing & other tasks to ensure

that the product or process is acceptable.2. Prevention costs

The sum of all costs to prevent defects such as:

a. Identify cause of defectb.Implement corrective action to eliminate the

causec. To train personneld.To re-design product or system.e.New equipment or modifications.


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3)Internal failure costsThe cost of defects incurred within the system:

a.Scrap

b.Re-workc. Repair

4.External failure costsThe costs of defects that pass through the system:

a.Customer warranty replacementsb.Loss of customer or goodwillc. Handling complaintsd.Product repair


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The rule of thumb says that for every rupee spent in


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The rule of thumb says that for every rupee spent inprevention, we can save ten rupees in failure & appraisalcosts.Often, increases in productivity occur as a by product of

efforts to reduce the cost of quality.

BENCH MARKINGIf you know your enemy and know yourself, you need

not fear the result of a hundred battles.According to Kehoe (1996) benchmarking can be definedas measuring the performance of processes within yourorganization, comparing these performance levels with

the best in class companies and where deficiencies exist,using the information on the best practices to improveyour organisations own business processes.

David Kearns defines benchmarking as the continuous


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David Kearns defines benchmarking as the continuousprocess of measuring products, services and practicesagainst the toughest competitors or those companiesrecognized as industry leaders.

There are several considerations in this definition

i. Continuous process.ii. Measuring.iii.Products, services and practices.iv.Companies renowned as industry leaders

Benefits of Benchmarking


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Benefits of Benchmarking1.Best practices from any industry to be creatively

incorporated into the processes of the benchmarkedfunction.

2.Identify a technological breakthrough3.It permits the individuals to broaden their background

and experience.4.It helps in meeting more effectively the end-user or

customer requirements.5.It supports in establishing goals (target setting) basedon a concerted view of external conditions.

6.It helps in determining true measures of productivityand effectiveness.

7.It assists in attaining a competitive position.8.It helps in becoming aware of and searching for

industrys best practices.9.Benchmarking allows individuals to see outside the

box. It provides for accelerating change and managing

Pitfalls of Benchmarking


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Pitfalls of BenchmarkingStatistics show that 70 percent of all processimprovement initiatives fail. The most common reasons ofthese failures are:

i. Lack of focus and priority;ii. Lack of strategic relevance;iii.Lack of leadership;iv.Lack of perseverance; and

v. Lack of planning.

Obstacles to Benchmarking


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Obstacles to BenchmarkingThe following are the most typical causes and obstacles

preventing the smooth and fast implementation ofbenchmarking practices:

1. Management not buying into the idea.2. No clear owner of the programme.3. Failure to consider customer-requirements.4. Change of sponsor before completion of the

programme.5. Programme taking too long and leading to loss ofinterest.

6. Not involving right staff in the programme.7. Team not measuring issues it agreed to address.

8. Programme causing too much disruption of work andnot seen relevant to work.

9. Conflicting objectives of the organization and those ofits benchmarking partners.


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Continuous Improvement (CI)Continuous improvement (CI) is a managementphilosophy that approaches the challenge of product and

process improvement as a never-ending process ofachieving small wins. It is an integral part of a totalquality management system.Continuous improvement seeks continual improvement ofmachinery, materials, labor utilization, and production

methods through application of suggestions and ideas ofteam members. Though pioneered by U.S. firms, thisphilosophy has become the cornerstone of the Japaneseapproach to operations.

Although management in both Japan and the Westhistorically have implemented CI in manufacturing plants,it has become quite common in services as well.

h f f


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The Key features of continuous improvement strategiesare:

Accountability is built in.

Incorporation of systematic learning (e.g., plan, do,check, act). Decisions based on facts. Diagnostic and remedial journey. Involvement of everyone within an organization.

Linkage of improvement activity with organizationalgoal.

Processes are divided into clear deliverables. Consideration of several solutions before

implementing the best.

oo s roce ures o1 V i f i l ti t


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1.Varies from simple suggestion systembased on brain storming to structuredprogrammes utilizing statistical process

control tools (SPC Tools)2.Deming wheel (PDCA) cycle3.Zero defect concept4.Bench Marking5.Six sigma

SPC Tools (Also known as Tools of TQC)StratificationCheck SheetProcess flow chart

Pareto analysisRun chartHistogramScatter diagramCauses & effect diagram (Fish Bone /Ishikawa

Diagram)

Deming wheel (PDCA cycle)


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g ( y )Another Tool is PDCA cycle:P= PlanD=Do

C=CheckA=ActIt is often called Deming wheel

Implement

Flow Chart

Cause & effect


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Pareto diagramsScatter diagrams

Runcharts

Control charts

Implement

recommendations Define process

& problems

Group

&

Value

Collect Data

2. Do

3.Check

4.Act

1. Plan

Cause & e ect

Define Problem

Suggest possible

causes

Deming Wheel


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PLAN PHASE (Also Known As Theme)In this Phase, specific problem is identified and

analysis is done using 5W2H Method

5W = - WHAT- WHY- WHERE- WHEN- WHO

2H = - HOW- HOW MUCH

DO PHASE: Is implementing the change- Should be done in a small scale first

CHECK PHASE: Deals with evaluating data collectedduring the implementation

Compare original goal vs. actual resultsACT PHASE: Improvement is codified as the new

standard procedure & replicated in similar processes

Bench Marking For CI


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Bench Marking is to find out what industry competitors &excellent performers are doing; find out the best practices thatlead to superior performance & see how it can be implemented

The Shin go system Fail safe design

Two aspects:i. Single minute exchange of die (SMED)-procedures to accomplish

drastic cut in set-up timesii. Use of source inspection and the poka-yoke system to achieve

zero defects.

(poka-yoke = fail safe procedures)Shingo argued that SQC methods do not prevent defects. The way to

prevent defects from coming out at the end of the process is tointroduce controls within the process. Inspection should be on100% items of three types.

a. Successive check inspectionBy next person or group leaderb. Self - CheckBy individual worker who produces the product.c. Source InspectionWorker checks for the errors that will cause defects.

POKA-YOKE (Fail Safe Procedures)


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( )All three types of inspections described above rely oncontrols consisting of Fail Safe Procedures of devicescalled POKA-YOKE.

POKA-YOKE includes such things as Chick Lists or special tooling that

i. Prevents the worker from making an error that

leads to a defect before starting a process.ii. Gives rapid Feed Back of abnormalities in the

process to the worker in time to correct it.

QUALITY CIRCLES


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A quality circle is a group of employees from the samework area and doing similar type of work voluntarily meetfor an hour periodically either every week or fortnightly to

identify and analyze

a.Quality of work they performb.Working conditions

The common number of employees for a quality circlegroup is about 8-10 individuals.

Pre-Requisites for successful quality circles

Members of Quality circles must have prior training inproblem solvingTop management support/attitudeActual implementation to be pre-ceded by carefully

developed plan for maximum returns.


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Problem solving cycle of a


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Quality circleoperation cycle

(c2) Data from

specialist if needed

(f) Review of recommendation

approval by management (g)Implementation

(a) Problem

Identification

(e)Presentation to

management

(c1) Problem analysis and

discuss alternatives

(d) Arrive at best

solution

(b) Problem

selection by

members

Quality circle

Structure of Quality Circle


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Every quality circle will have a leader and a deputyleader. For three or four quality circles there will be afacilitator, whose job is to co-ordinate the functioning of

the quality circles. In an organization, there will be a highlevel committee consisting of the CEO and two othersenior members to monitor the quality circle activities andformulate guidelines for effective functioning including

rewarding system. Each quality circle will have membersranging from 8 to 10 in number. All must havevolunteered to join this movement. The structure ofquality circle is shown in Fig. below

Executive committee


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Steering committee

Facilitator Facilitator Facilitator

Quality circle Quality circle Quality circle

Leader

Dy. Leadear

Manager

Member

Member

Structure of QualityCircle

The benefits of quality circle1 Develop mutual trust and cooperation between management and


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1. Develop mutual trust and cooperation between management andworkers as well as involve the workers in the decision makingprocess in their work area.

2. Improvement in productivity.

3. Changes the total attitude to a constant, self renovation force ofbusiness enterprise.

4. Develops the knowledge management culture in the organizationat the workers level.

5. Improves the quality of the products and services

6. Leads to increase in sales and reduction in the cost of production.7. Focus on higher safety and reduction in accidents.8. Ensures better housekeeping.9. Increases profitability by reduction in waste.10.Creates better motivation and involvement of the employees

leading to reduced absenteeism & Grievances11.Leads to enriched quality of work life.12.Creates an atmosphere of positive and proactive work force with

harmony and mutual trust.13.Creates better human relations and participative culture.14.Promotes job knowledge.

15.Creates a greater sense of belonging.

RE ENGINEERING


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The fundamental rethinking and radical re-design ofbusiness processes to achieve dramatic improvementsof performance in cost, quality, service & speed

Re engineering not for incremental increase inimprovements but for making Quantum LeapsVisualizing and stream-lining any or all Businessprocesses through combining, eliminating or

restructuringIt is a top down programme since lower down;perspective to visualize changes may not be there.It is different from OD, particularly with respect tominimal participation of employees at various levels.

HOW TO MAKE RE-ENGINEERING & OD CONGRUENT


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A. Making process as humane as possible through

RetrainingTransfer

Retirement incentivesAvoiding layoffs

A. Those who look for OD-Type values and processes canlook for avenues for meaningful involvement of

employeesB. People with OD skills can help emerging new teams to be

more effective for successful implementation of re-engineering (Re-Engg. Teams, steering committee,Process teams to replace functional deptts.)

C.OD. knowledge about how to design parallel structures isrelevant to re-engineering.

D.When large scale systems changes affecting number oforganizational units, number of people affected, the numberof org systems altered and /or depth of cultural changes areinvolved, multiple types or O.D. interventions are utilized.

i. Reduction in hierarchical levels from say eight to fourh f l d h l ld


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ii. Shifting to a more participative leadership style wouldeffect responsibilities of employees at every level &would require changes in work flow, reporting relation

ships, jobs description & training programmesAdvantages Of Re-Engineering (Positive Impact)

1.Improvement in entire org. as a whole.2.Better systems & mgt. improvement in areas of

i. Products & servicesii. Designing & operationsiii.Improved system operations

1.Takes advantage of improved technology

2.Improved application of industrial engg. in areas ofi. Organizational strategiesii. Management functionsiii. Plant utilizationiv. Quality improvement

v. Creativity & innovation

5. Improvement in customer satisfaction


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Negative Impact of Re-Engineering

Does not pay much attention to the social system of

organizations relative to change processes & re-design of work. No consensus approach & noinvolvement of people lower down in the org.Strained industrial relations because re-engg. Would

result in large lay-offs & dislocation of people.Impact of layoffs & thus resistance to re-engg. canbe minimized through

oRe-training & re-deployment

oReduction through attritionoTransfer to other locations, comprehensive &carefully designed out-placements programmesoEarly retirement inducements

oAdequate notice period to employees before- HISTORICAL EVOLUTION OF TQM

C titi i t d d b tt lit f


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Competitive environment demands a better quality ofproduct or service at lower rates. The impact of poorquality on any organization leads to:

i. Low customer satisfaction and low market shareii. Low productivity, revenue and profitiii.Low morale of workforceiv.More rework material and labour costsv. Poor quality of goods and servicevi.High inspection costvii.Higher process bottlenecks and delay in product

shipment

viii.Higher work-in-progress inventoryix.High repair costsx. High material wastage and scrap

Evolutions of QualityTotal quality is not a revolutionary but an evolutionary concept It


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Total quality is not a revolutionary but an evolutionary concept. Ithas evolved over the years as shown

1975 1980 19851990 1995 2000

OPERATIONS CUSTOMERS INNOVATIONS

Quality of

Work life

Quality

Circle

Productivity

Employees

Involvement

Quality Total

Quality

Self-

Directed

Teams

Total Quality

Control /

Management

Self-Directed & self-

Managed Teams

The Evolution of Quality Means and

Evoluation


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900 1920 1940 1960 1980 1990 2000

Years

Operato

r

Forem

an

Inspecti

on

Statisti

cal

Quality

Control

Total

Quality

Control

(TQC)

Total Quality

Control

Company wideControl

Total Quality

Management

TQM

The Evolution of Quality over the

The focus has also undergone a shift form operations tot t i ti I f t i


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customers to innovation. In any manufacturing company,three management concerns-quality, cost andproductivity-must be evaluated in relation to the

customer.

Definition of QualityA b f d fi iti f lit h b d d


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A number of definitions of quality have been propoundedby experts.

1. Quality is fitness for use or purpose.

- Joseph M. Juran2. Quality is conformance to requirements.

- Philip B. Crosby3. A predictable degree of uniformity and dependability at

low cost and suited to market.W. Edwards Deming4.. . . development, manufacture, administration and

distribution of consistently low cost products andservices that customers need and want. - Bill

Conway5. Total composite of product and service characteristics

of marketing, engineering, manufacturing andmaintenance through which the product and service in

use will meet the expectations of the customer.-

6.Quality is the degree of excellence at an acceptablep ice and cont ol of a iabilit at an acceptable cost


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price and control of variability at an acceptable cost.7.The totality of features and characteristics of a product

or service that bear on its ability to satisfy stated or

implied needs of customers. - ISO 840:Quality Vocabulary

In brief Quality is one which satisfies customers needsand continuously keeps on performing its functions as

desired by the customers as per specified standards.

New Definition of QualityQuality is about organizations, quality is strategic, quality

is for everyone, quality is led by management, quality isappropriate grade and quality is \aboutimprovement-Big Q.A good quality process changes the way things are doneby:


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What is total Quality?


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What is total Quality?Total quality is defined as the mobilisation of the wholeorganization to achieve quality continuously, economically

and in entirety. Total quality not only satisfies butdelights the customers by offering attractive features inproducts and services.Total Quality control (TQC)TQC, TQM and Total Quality are synonymous terms and

used interchangeably in the field of quality.Total quality Control is an effective system forintegrating the quality development and improvementefforts of various groups in an organization so as to

enable marketing, engineering, production and service atthe most economical levels which allow for full customersatisfaction.

Factors Affecting TQCThe scope of total quality control (TQC) encompasses all


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The scope of total quality control (TQC) encompasses allactivities and stages of industrial life cycle, viz.

1. Marketing evaluates the level of quality which customers want

and for which they are willing to pay.2. Engineering reduces this marketing evaluation to exactspecifications.

3. Purchasing chooses, contracts with, and retains vendors forparts and materials.

4. Manufacturing (engineering) selects the jigs, tools, andprocesses for production.

5. Manufacturing supervisions and shop operators exert a majorquality influence during parts making, sub-assembly and finalassembly.

6. Mechanical inspection and functional tests check conformance

to specifications.7. Shipping influences the caliber of the packaging and

transportation.8. Installation and product service help ensure proper operation

by installing the product according to proper instructions and

maintaining it through service.

Q FactorManagers must appreciate the broader meaning of


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Managers must appreciate the broader meaning ofquality. They should know the difference between big Qquality and little quality. Big Q quality is important

because it encompasses cost, delivery and safety as wellas the traditional view of conformance quality. Big Qfactor is commonly used in various terms of Total qualityManagement, for example, TQM, TQC, SQC, QA, etc.Dimensions of Quality (Kanos Model)Noriaki Kano and others have proposed the concept oftwo dimensions of product quality:

Must be (expected and performance) quality and

Attractive (excitement) quality. Kano gives thefollowing three features of quality.

Expected Features


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Expected Features Fundamental functions must be present. Absence of these features dissatisfies,

Performance Features These features create satisfaction if customersexpectations are exceeded.

There will be dissatisfaction if they fall short ofexpectations.

Excitement Features Innovations beyond customers awareness. Even minor items, if perceived by customers as of

superior value, can enhance market share.

They must be based on intimate knowledge ofcustomer perception, product function and usageconditions to be successful.

CUSTOMER SATISFACTION


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CUSTOMER FOCUSIt is said that in an organization quality begins and ends withcustomers. The most coveted Baldrige Quality Award also stresses

on customer related issues. Out of 1000 pts, about 300 pts areattributed to customers,Customer WindowCustomers decisions are mostly controlled by perception. Therecan be a gap between what is perceived to be good and what is

important to the customer. The customer window highlights therelationship between the perception of the customer about theproduct attributes and the importance of those attributes fromtechnical point of view. The priority of focus is indicated in thecustomer window. Many a times survey among the customers

reveal that factors in the top left quadrant of the customerwindow are significant. Organizations attempt to focus on this,without realizing that these attributes can only have short termdividends. Attributes in the top right quadrant needs to befocused first. Some important factors will have very poor

perception among customers. These are critical ones.

Very good


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III I

IV II

Very good

Customer

Perception

Poor

Not at all Very much

Importance to customer

Customer Satisfaction ModelCustomer satisfaction model relates customers


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Customer satisfaction model relates customer ssatisfaction and value addition. It is schematicallyrepresented in Fig. The value addition in the product or

service is plotted along the x -axis and the satisfactionalong the y axis.


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Type B CustomersCustomer

Without expectations

Value addition not

available

Type A customersCustomer

With expectations

Value addition

available

Delighted

Customers

Dissatisfied customers

Points for customer satisfaction


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1. Customer satisfaction should be the primary driving force of TQM.2. As a first step, analyse who the customers are and assess what

problems they experience.

3. The company should cooperate with the customer to resolve theproblems experienced by them.4. One-to-one relationships should be established between the

company and its customers.5. Analysis of the sales process should be undertaken to enhance

customer satisfaction, and also to increase sales volume andreduce costs inherent in the process.

6. The concept of customer satisfaction should be internalisedwithin the integral part of employee care rather than stand alonein the form of behavioural training for customer contact staff.

7. An organization should encourage customer complaints as an

opportunity for quality improvement.8. Customer relations are of great importance. Relationships between

the company customers and suppliers should carry equal weight.9. Active partnerships between the business and its suppliers should

be established. Customers should be delighted by offering total

quality products for meeting and exceeding their expectations.

Techniques for measuring customer value customer perception of quality


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customer perception of qualityPersonal Interviews: Ask them in personal interviews,one on-one, in on /site meetings, telephone calls, or

teleconference. Discussion should be guided by astructured set of questions.Protocol Analysis: called content analysis, can be usedto make sense of verbal data gathered through open-ended interviews or discussions.Focus Groups: Uses an unstructured interview toencourage a group of customers to discuss their feelings,attitudes and perceptions about a particular topic.Laddering: Laddering provides a method for identifying

the needs, desires, wants or values of customers, and theproduct attributes instrumental in serving them.Laddering is most often used in individual interviews, butcan be used in focus groups.

Trade-off Analysis: Once a set of attributes has beenidentified as potential components of product or service


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identified as potential components of product or servicevalue, managers need to determine the relativeimportance of each.

Market Test: A market test always involves havingtarget customers try the product, usually under the samecircumstances in which they would use similar products.Direct Observation: Managers can often improve theirunderstanding of value by directly observing thecustomers at each stage of decision making and use ofthe product or service.Other Sources of Data on customer: Traditionally usedby managers collect details of complaints, returns,

warranty date etc.After Sale Feedback


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The value analysis team is a cross-functional team. If thebj i f l l i i h f h k l


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objective of value analysis is enhancement of the market value,then the value analysis team leader will be the head of themarketing department. If the objective of value analysis is to

reduce the cost or the product innovation, then the value analysisteam leader will be the head of the manufacturing.Cost of valueThe value is of two types, namely the use value and the esteemvalue.

Use value: The product quality is fundamentally defined asfitness for use. Value analysis is primarily concerned with the usevalue. This is also known as the primary or the basic value of theproduct.Esteem value

The esteem value is the enhanced value associated with a brandor a product created by smart marketers. This is a notional orsnob value for which the customer is ready to pay higher. This isalso known as the secondary value associated with the product.

Steps in Value Analysis


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The following steps are to be followed for the valueanalysis.

1. Collect data about cost function, customer needs, historyand likely future developments related to the productand its use. Determine the function of the product.

2. Develop alternative designs. The selected alternativesshould be able to fulfill the functional requirement of theproduct.

3. Ascertain the cost of the alternatives.4. Evaluate the alternatives in all respect. The alternative

which fulfills all the basic or primary value considerationsand maximum number of secondary value considerationsis the ideal alternative subject to the cost considerationwhich should be minimum.

5. Recommend and implement the best solution. Identifythe control point and devise a plan for periodicmeasurement of the performance and correct thedeviations if any.

Value Analysis - Areas of ImprovementIn value analysis, the areas of improvements are basically


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In value analysis, the areas of improvements are basicallyidentified in four areas. They are:

a.The functional aspect of the product and services,b.The intrinsic cost of the materials,c. Manufacturing andd.Specification.

AIMS OF VALUE ENGINEERING

Simplify the productUse cheaper & better materialsModify & improve product design.Use efficient processes

Reduce product cost.Increase utility of product by economical meansSave money or increase profits

Steps / Procedure in Value Engineering


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Identify the productCollect the relevant informationDefine different functionsDefine / create different alternativesCritically evaluate the alternativesDevelop the best alternativeImplement the alternative

Step I: Identify the Product

Any design change should add valueValue can be applied to a product as a whole or to

its subunits

Step II: Collect relevant information


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Technical specifications with drawingsProduction processes, machines, layout, instructionsheet, etc.Time study details & manufacturing capacityComplete cost data & marketing detailsLatest developments in related products

Step III: Define different functionsDefine primary, secondary and tertiary functionsSpecify value content of each function & identifyhigh cost areas.

Step IV: Create different alternatives


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Through brainstorming sessions based on detailsavailable from above, create different alternativesAll feasible and non-feasible suggestions arerecorded without any criticism rather participantsare encouraged to express their views freely

Step V: Critically Evaluate the Alternatives

Compare, evaluate, critically assess for theirsuitability & feasibility as regards their financial &technical requirements. Ideas technically sound andhaving lesser costs are further developed

Step VI: Develop the best alternative

Development plans comprising of drawingsketches, building of models, conducting

discussions with purchase section, finance section

Step VII: Implement the Alternative


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The best alternative is converted into a proto-typemanufacturing model which ultimately alternatelygoes into operation and its results are recorded.

Advantages o Value Engineering

It is a much faster cost reduction technique.

It is less expensive technique.Reduces production costs and adds value to salesincome of the product

Applications of value engineering

Machine tool Industries.Auto IndustriesImport substitutes, etc

CREATING QUALITY CULTURESeven S Framework for Change


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gMckinseys 7-s framework comprises elements such asstrategy, structures, systems, staff, skills, styles and

shared values. Strategy, structures and systems arecalled 3-hard Ss viz., strategy, structure and systems fordoing things. It is a good start but not enough.Organizations which are truly excellent and strive toimprove quality in everything include: IBM, Motorola,

Corning, 3M, Down Chemicals, Toyota, Matsushita,Mitsubishi, Hitachi, ICI, Pedigree, Pet Foods, Hewlet-Packard, etc. All these use the 3-hard Ss approach andsupplement it with the 4-soft Ss viz., staff, skills, styles

and shared values.The soft Ss approach relate to people, their actions

and the roles they play. Improvement does not comeform strategy, structure and system. It comes from thesoft Ss per se. Improvement in quality, movement in


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Structure

SystemsStrategy

Structure

Values

Skills Styles

Staff

Resistance to cultural change


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People are afraid that the change will affect their way offunctioning.People perceive that they will lose their control overthings.There is a personal uncertainty that they will not be ableto live up to the expectations of others.The change may mean more work for them.

There may be past resentments against management.They think that TQM will die its natural death aftersometime like several other concepts.There is an attitude that TQM will go away if I ignore it.They are unwilling to take ownership and feel committed.

They think it is somebody elses responsibility.They have the attitude first you change, then I will.They think that others will find out that what I have beendoing over the years is wrong. I could be penalized for mymisdeeds.

Corporate CultureK h (1996) d fi i ti lt th h d


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Kohoe (1996) defines organization culture as the sharedvalues and norms of behaviour of the individuals withinthe organisation.

CREATING QUALITY CULTURE (CONTINUED)


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Differences in quality cultures:

Negative quality culture (Hide the scrap scenario)

Positive quality culture (Climb the ladders to delight the

customer scenario)

TQM WORK CULTURE

Culture change is the secret to implementing TQM. Founders ofcompanies create the original cultures. The beliefs of the founder

and the senior managers teams are translated into rules,

systems, norms and styles of managing. These are passed on to

people who join the company.

Many traditional Indian companies portray the old culture which is

not exactly geared up for TQM. The culture, they say, is

something unique to Japan. However, this is not true and has

been proved wrong by Japanese themselves, when they started

collaborative ventures in foreign counties like the US and India.

Japanese Management is as exportable as its products. Janpanese

guiding principles-granting employees broad authority to organize


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g g p p g g p y y g

their tasks and insisting on high quality from workers and suppliers-

are now proving themselves in the US towns.

There is also evidence to suggest that the values inherent in theculture are rapidly being adopted by employees as their personal

values.

Values and CultureValues are the building blocks of a culture. Values are stable, long-term

beliefs that are hard to change. They define what is right or wrong; good

or bad; and correct or incorrect.

Requisite Changes to Implement Quality Culture


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From Traditional Culture To TQM Culture

Hierarchical Style Participative style

Top down information

flow

Top down, lateral and upward

information flow

Inward quality focus Customer defined quality focus

Functional Focus Process focus

Short-term planning A vision for the future

Episodic improvement Comprehensive / Continuous

improvement

Top down initiatives All staff involved and engaged

Manage and delegate. Empower

Direct Counsel Ownership and participation Functional and narrow

scope of jobs

Integrated functions

Enforcement Promoting mutual trust

Fire fighting with few

individual/group

Team initiatives group focusing on

Continuous improvement.

DEVELOPING TQM CUTLURE

Developing TQM Culture


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Developing TQM Culture.

Superior quality can be obtained by pursuing two courses of action.

1. developing technologies to create products and processes which mecustomers, needs and

2. stimulating a culture throughout the organization that continually view

quality as a primary goal.

Step for Creating TQM Culture

Management accountability and a deep sense of responsibility towards

employees is the starting point.

Management thoughts and actions towards delighting its customers.

Removing organizational boundaries and internal competition.

Using fact-based decision making.

Use of Kaizen. Continuous improvement must be encouraged.

Do not use specially designed organization structures for TQM.

There ill initiall be a need for q alit ass rance department This


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There will initially be a need for quality assurance department. This

department should be include some specialists who will help

develop training courses, assist other parts of the organization in

difficult problem solving and assist senior management in theirevaluation of the management system.

Use natural organization existing in the company to promote and

implement your approach to quality.

To conclude change in the culture of a company are a natural

consequence of implementing TQM. Corporate cultures develop

over time and can be traced to the behavior and values of scenario

management. Top management need to apply the underlying

values and concepts of TQM daily. They must show by examplethat the customer is the first. They must listen to and respond to

employees ideas. Managers must see in their organizations that all

employees are respected that decisions are based on facts, and

that cooperation among employees must continue to be practiced.


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Process control or statistical


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process control (SPC)

SPC involves testing a random sample ofoutput from a process to determine

whether the process is producing items

within a pre-selected range. When the

tested output exceeds the range, it is a

signal to adjust the production process to

force the output back into the acceptable

range. This is accomplished by adjustingthe process itself.

Acceptance Sampling


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Acceptance Sampling

Acceptance sampling is frequently usedin a purchasing or receiving situation,

while process control is used in a

production situation of any type.

SQC for process control


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SQC for process control

Mainly, SQC is used for controlling qualityduring production in a mass production

industries which produce standard

products. SQC for process control is

based on the probability theory. When

several identical parts are produced,

most will approximately be the same

while few will be a little large & few willbe a little small. When plotted with size

on horizontal line, a normal or bell-shaped

curve of following type is obtained.


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Variation in size between 0 995 and 1 005


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Variation in size between 0.995 and 1.005with most measuring 1.000 are due to

chance causes. Chance causes are thosecauses which operate randomly and

independently of each other and follow

normal law of errors. Chance causes are

inherent and cannot be controlled orprevented. Chance causes are ignored

because any effort to eliminate them is

uneconomical and may be counter-

productive too. Vibration of a machine,voltage fluctuations, variation in

temperature, etc. are chance causes.

Assignable causes or Non-


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random causes

These can be easily identified asresponsible for variations and are not

distributed normally. Wear & tear of machine

parts, a worn out tool, setting of machine

being changed unintentionally, etc. areassignable causes. When it is known that an

improper size is made as a result of an

assignable cause, it is possible to detect the

cause & rectify it. If the size measures beyond 1.005 or below0.995, it is not due to chance causes but

because of assignable causes.

Advantages of SQC in industry


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Advantages of SQC in industry

1. Through SQC an objective check is maintainedon the quality of the product

2. Through SQC, it can be known whether the

manufacturing process is under control or not

and if it has gone out of control, remedialmeasures can be applied.

Preventive measures can also be initiated if there

is a signal that the process is soon going to be

out of control. Thus, waste of material, etc. is

avoided

3. SQC system, if adopted & strictly followed,

increases industrys goodwill since users may

rely on its products with greater confidence.


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4. Quality of products can be defended in anyenquiry on the basis of SQC records.

5. SQC has a healthy impact on workers since

they know that quality is being checked and

accordingly they work efficiently & withalertness.

6. Inspection expenses under SQC system are

reduced since sampling inspection is done as

against 100 % inspection.

Control Charts


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Control Charts

The control of quality in the manufactured product throughprocess control is achieved through control charts. Based on theory of probability and sampling, the presence ofassignable causes of erratic variations are detected in the

process. These causes are identified, eliminated & process

is stabilized & controlled at desirable performances.

A typical control chart consists of following three horizontallines on the graph

1. A control line to indicate the desired standard of the control level of the process.

2. An upper control limit indicating the upper limit of tolerance.

3. A lower control limit indicating the lower limit of tolerance.


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These limits are established to assist injudging the significance of the variation

in the quality of the product.

The control limits are different fromspecification limits (which refer to qualitycharacteristics of individual unit of

product)

These control limits are used to evaluatethe variations in quality from sample to

sample.

Out of Control


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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Quality Scale

Central Line (Average)

Sample Numbers

Upper Control Limit (UCL)

Lower Control Limit (LCL)

3 Sigma

3 Sigma

Out of Control

Out of Control

Process is under control if no points liebeyond the control limits. An out of control


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y

situation includes1. Point(s) outside control limits (UCL & LCL)

2. Change or jump in level when successive plotted pointsare on one side with respect to central line, though within

control limits.

3. Trend or steady change in level A steady or progressive

change in plotted points called a trend.

These may be due to machine deterioration ortool wear. To be corrected before it goes too

far.

Control charts for variables are used formeasuring quality characteristics. Control Chart For Sample means (X-chart) Control chart for sample ranges (R-chart)

Acceptance Sampling


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Acceptance Sampling

Acceptance Sampling is performed ongoods that already exist to determine what

percentage of products confirm to

specifications. These products may be

items received from another company andevaluated by the receiving deptt or they

may be components that have passed

through a processing step and evaluated by

company personnel either in production orlater in warehousing function.

Acceptance Sampling is executed through asampling plan.


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Single Sampling plan Based ondetermination of quality from evaluationof one sample. Two samples are also

used called double sampling.

Acceptance Sampling is carried out when100% inspection is costly or inspection

may be destructive. The whole lot of

items are accepted if the sample items

conform to the specifications otherwise itis rejected. Sample items are considered

to be representative of the whole lot.

Random Sample


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Random Sample

A random sample is one in which each unitin the lot has an equal chance of being

included in the sample and the sample is

likely to be representative of the lot.

Variables are quality characteristics thatcan be measured on a continuous scale. E.g.

Diameter of a shaft

Attributes are quality characteristicswhich can be classified in one of the two

categories namely good or bad; defective or

non-defective


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Type I Error This is an error insampling inspection. A sample from the

output of the process may lead to

conclusion that the process is out of

control whereas process may be

operating as intended.

Type II Error occurs when the process isnot working as intended, but the samplingerror causes one to infer that the process

is satisfactory.

Acceptable Quality Level

(AQL)


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(AQL)

Acceptable Quality Level is the maximumpercentage or fraction defective that is

considered as the overall process

average. The lots having quality equal to

AQL or better have a high probability of

acceptance (i.e. 0.95)

The objective of producer is to ensurethat the sampling plan has a lowprobability of rejecting good lots. Lots are

defined high quality if they contain no

more than a specified level of defects.

Lot Tolerance Percent

D f ti (LTPD)


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Defective (LTPD)

This is the upper limit of the percentageof defective products in an individual lot

that the consumer is willing to tolerate,

even if the process is aceptable. This is

also known as LIMITING QUALITY LEVEL

(LQL). Lots having quality equal to LTPD

or worse have a very low probability of

acceptance (0.10)

Producers Risk ()


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Producer s Risk ()

The probability associated with rejectinga high quality lot is denoted by and is

termed the Producers Risk.

This is the risk of getting a sample whichhas a higher proportion of defectives thanthe lot as a whole and thereby rejecting a

good lot based on sample evidence i.e. a

lot as good as AQL will be rejected by isof a particular sampling plan. While using

acceptance sampling plans, producers

hope to keep this risk as low as 5%.

Consumers Risk ()


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Consumer s Risk ()

The probability associated with accepting a lowquality lot is denoted by and is termed as

consumers risk.

This is the risk of getting a sample which has a lowerproportion of defectives than the lot as a whole and

thereby accepting a bad lot as a good lot i.e. it is theprobability that a lot with a percentage of defective

equal to LTPD will be accepted by the sampling plan.

While using sampling plans, consumers want to keep

this risk () as low as 10%.

The selection of particular values for AQL, , LTPDand is cost tradeoff or more typically, on company

policy or contractual requirements.

Average Outgoing Quality

Li it (AOQL)


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Limit (AOQL)

The main objective of acceptance sampling plansis to guarantee a certain quality level, no matter

what the incoming lot quality may be maintained

by the producer.

The fraction defective remaining in the lot afterinspection is known as outgoing quality of thelot. The average fraction defective remaining in the

lot after inspection is termed as average outgoing

quality (AOQ). Obviously, it is a function of

incoming lot quality. The fraction defectivemaintained by the producer. The maximum value of

AOQ subject to variations in to is known as

average outgoing quality limit (AOQL).

Average Sample Number


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Average Sample Number

Average number of items that must beinspected for coming to a decision

(acceptance or rejection) is called

Average Sample Number (ASN)

Operating Characteristic

C (O C C )


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Curve (O.C. Curve)

The following can happen when we go for acceptancesampling plans.

1. We accept good lots

2. We reject bad lots

3. We may accept bad lots

4. We may reject good lots

In vast majority of cases, we do accept good lots&reject bad lots. On rare occasions, we may accept

bad lots based on sample evidence although lot may

be good. When good lot is rejected, the error is knownas Error-I and the risk of rejecting a good lot based on

sample evidences is known as producer's risk ()

which should be kept as low as possible.


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When a bad lot is accepted based on sampleevidence, the error is known as Type-II error

and the risk of accepting a bad lot as good is

known as consumers risk () which again

should be kept as low as possible.

The operating characteristics (OC) describesan important feature of acceptance sampling

plans. It shows how well an acceptance plan

discriminates between good & bad lots.

1.00

0.95

Producersrisk () 5 %


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0.10

0 1 2 3 4 5 6 7 8 9 10AQL LTPD

Consumersrisk () 10 %

Actual percent defective (p) in the lot

Operatin Characteristics Curve

n = sample size

c = acceptance number(Maximum

number of defection in asample to accept the lot)

In this figure, a good lot may be defined as having nomore than 1 % defectives This is called acceptable


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more than 1 % defectives. This is called acceptable

quality level (AQL). If there is 1% actual defectives in

a lot, the probability of accepting the lot should be ashigh as 95% and then the probability of rejecting a

good lot is 5%. The probability of rejecting a lot at

the AQL quality is known as producers risk () . Let

us define a bad lot as having 5% or more defectives.

This is known as lot tolerance percent defective(LTPD). The probability of accepting a lot with 55

defectives should be as low as 10%. This is called

the Consumers risk (). But the probability of

rejecting a lot with 5% defectives or more is 90%.


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Sampling plans do not provide perfectdiscrimination between good & bad lots.

Some lots of low quality may be accepted

while some lots of very good quality may

be rejected due to sample evidence.

Ideal OC Curve


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The ideal OC curve can be achieved only through100% inspection. However, in practice we cannotgo for 100% inspection of big lots, the OC curve

selected should ensure that as the lot quality

decreases (i.e. % defectives increase), the

probability of acceptance of such lots should

decrease, although relationship is not linear.

N = 100 units. If

defectives < 2%,

lot accepted &

if 72%, lot is rejected

1.00

0 1% 2%

%a e of defectives

RejectAccept

Process Control with AttributeMeasurements using p charts


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g p

(Fraction Defective Chart)

Measurement by attributes means takingsamples and using a single decision the

item is good or it is bad.

We can use simple statistics to create pchart with a upper control limit (UCL) andlower control limit (LCL). We can draw these

control limits on a graph & then plot the

fraction defective of each individual sample

tested. The process is assumed to beworking satisfactorily when samples taken

during the day periodically continue to stay

between the control limits.

p = Fraction defective


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p = Total number of defects from all samples

Number of samples X Sample size

Sp = p (1-p)

n

UCL = p + zsp

LCL = p zspp = central or control line of p chart

Sp = Standard deviation

n = sample size

z = number of standard deviations for a specific confidencez = 3 (99.7% confidence)

z = 2.58 (99.0 % confidence)

z = 1.96 (95% confidence level)


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LCL

__

Central Line (p)p

Out of control (UCL)

Sample Size

Process Control with variables

measurements using X and R charts


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measurements using X and R charts

In variables sampling, actual weight, volume,number of inches or other variables

measurements are measured and plotted on a

chart to determine acceptability or rejection of

the process based on these measurements. Fourissues to address in creating a control chart:

1.Size of samples sample size to be small so that

it is taken within a reasonable length of time &

to reduce cost of larger sample. Sample size of

five units preferred. For sample size exceeding

15 it would be better to use X charts with

standard deviation () rather than X charts with

range R.

2. Number of samples to set up the charts, 25

or 30 samples be taken and once chart has


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or 30 samples be taken and once chart has

been set up, each sample is compared and a

decision taken whether process is undercontrol.

3. Frequency of samples It is trade off between

cost of sampling (more so if it destructive

testing) vis-a-vis benefit of adjusting thesystem. Usually start with five units every half

an hour & reduce frequency of sample as

confidence in process builds up.

4. Control limits standard practice is to setcontrol limits 3 standard deviations about the

mean (99.7% confidence level). Thus, if any

sample falls outside this band it indicates that

the process is out of control.

X Chart


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If the standard deviation of the process distribution isknown, the X chart may be defined as

UCL X = X + zsx

LCL X = X - zsx

Where:

sx = S = standard deviation of sample means

ns = standard deviation of the process distribution

n = sample size

x = Average of sample means or a target value set for the

process

z = number of standard deviations for a specific confidence

(typically z = 3)


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An X chart is simply a plotting of themeans of the samples that were taken

from a process. X is the average of the

means.

In practice, however, the standarddeviation of the process is not known.

R - Chart


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An R Chart is the plotting of the Rangewithin each sample.

Range the range is the difference betweenthe highest and the lowest numbers in the

sample

An R Chart is the average of the range ofeach sample.

X =________

n

Where:x = mean of the sample


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x = mean of the sample

i = item number

n = total number of items in the sample

X =m

Upper control limit = UCL x = x + A2R Lower Control limit = LCL x = x A

2

R

Upper control limit for R = UCL R = D4R Lower Control limit for R = LCL R = D3R

Where:X = the average of the means of the samples


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g p j = sample number m = total number of samples Rj = Difference between the highest & lowest

measurement in the sample

R = Average of measurement differences R for allsamples or

R =m

X Chart (Mean Chart)


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Lower Control Limit (LCL X)

Central Line (X)Samplemeans

(x)

Upper Control Limit (UCL X)

Sample Numbers

Range Chart (R-chart)


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Lower Control Limit (LCL R)

Central Line (R)SampleRange

(R)

Upper Control Limit (UCL R)

(Sample Numbers)

C - Chart


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This chart applies to the number of non-conformities in samples of constant size.C is a variable representing the number of

non-conformities (defects) in each

sample. Usually the sample size is

considered to be one. The control limitsof this chart are based on poission

distribution.

Some applications of C-chart:1.To control number of non-conforming rivets in


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an aircraft wing.

2.To control the number of imperfectionsobserved in a galvanized sheet.

3.To control the number of surface

imperfections on a large casting like gear

blank which is used to rotate kiln in cementplants.

4.To control the number of defects in final

assemblies (like T.V., Radio, Computer etc.)


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The formulae for control limits are: UCLC = c + 3 c LCLC = c -- 3 c Where c is the mean of number of non-

conformities. Also, this is the central line

in control chart.

The plotting of c (number of defects ineach sample is done on the control chart(c-chart)


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0 1 2 3 4 5 6 7 8 9 10

C

C Chart

Upper Control Limit

Central Line

Lower Control Limit

Mean (c)

Sample Number

Classification of quality

control techniques


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control techniques

Control Charts areused to control in-

process quality

Acceptance sampling

aimed to controlquality of incoming

materials

How much to inspect & how

Often


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Often

Cost of passing

Defectives

Cost of

Inspection

Costs

Total Cost

Amount of Inspection

C Chart(Number of defects per unit)


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( p )

C = Number of defects per unit C = Average no of defects of all samples UCLC = c + 3 c LCLC = c -- 3 c CLC = c

Q. During an examination of equal length of

cloth, the following are the number of defects

observed:


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observed:

2, 3, 4, 0, 5, 6, 7, 4, 3, 2

Draw a control chart for the number of defects &

comment whether the process is under

control or not?

Ans: Average number of defects in 10 sample

units is:

C = C = 2+3+4+0+5+6+7+4+3+2

k10

= 3.6


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9.3 (UCL)


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Sample Numbers

3.6 (CL)

LCL = 0

X Chart & R ChartQ The following data gives the measurements of axle of


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Q. The following data gives the measurements of axle of

bicycle wheel (in mm.) 12 samples were taken so that

each sample contains the measurements of 4 axles.Obtain control limits for X Chart & R Charts and comment

whether the process is under control or not.

Sample nos.

Given the value of constants from table of sample size (n=4)

A2 = 0.73, D3 = 0, D4 = 2.28

1 2 3 4 5 6 7 8 9 10 11 12139 140 142 136 145 146 148 145 140 140 141 138

140 142 136 137 146 148 145 146 139 140 137 140

145 142 143 142 146 149 146 147 141 139 142 144144 139 141 142 146 144 146 144 138 139 139 138

SolutionSample Sample Values Total Sample

Sample (0.0001 inch) Mean (x) Range


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pNo.

( ) ( ) g

(1) (2) (3) (4) = (3) 4 (R) (5)

1 139 140 145 144 568 142.00 6

2 140 142 142 139 563 140.75 3

3 142 136 143 141 562 140.50 7

4 136 137 142 142 557 139.25 65 145 146 146 146 583 145.75 1

6 146 148 149 144 587 146.75 5

7 148 145 146 146 585 146.25 3

8 145 146 147 144 582 145.50 3

9 140 139 141 138 558 139.50 310 140 140 139 139 558 139.50 1

11 141 137 142 139 559 139.75 5

12 138 140 144 138 560 140.00 6

Total x =

1705 50

R = 49

From the above table we get:

x = 1/12 x = 1705.50/12 = 142.125

R = 1/12 R = 49/12 = 4.08


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We are given that for n = 4, A2 = 0.73, D2 = 0, D4 = 2.28

X Chart 3 control limits are given by:

UCL x = x + A2R = 142.125 + 0.73 x 4.08 = 145.10

LCL x = x A2R = 142.125 0.73 x 4.08 = 139.15

CL x = x = 142.125


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UCL (145.1)

LCL (139.15)

CL (142.12)

Sample Number

SampleMean

(x)

Since the sample Point (means)corresponding to sample numbers 5, 6, 7 and

8 lie outside the control limits, the x chart


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8 lie outside the control limits, the x chart

indicates lack of control in process average

. This suggests the presence of someassignable causes of chaotic variations

which must be detected and corrected.

R Chart: 3- control limits are given by:

UCLR = D4R = 2.28 x 4.08 = 9.3024 LCLR = D3R = 0 x 4.08 = 0 CLR = R = 4.08 Since x-chart shows lack of control, the

process cannot be regarded in statistical

control although R-chart exhibits statistical

control.

UCL (9.3)


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Sample Number

SampleRange

LCL (0)

CL (4.08)

Control Charts for Attributes:


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As an alternative to x and R or x and s charts wehave the control charts for attributes which areused:

When we deal with quality characteristics whichcannot be measured quantitatively. In such

cases the inspection of units is accompanied byclassifying them as acceptable or non

acceptable, defective or non defective.

When we deal with characteristics which areactually observed as attributes although they

could be measured quantitatively, e.g., go and

not-go gauge test results.

Question on x chart & R chartQ. You are given values of sample means (x) and the ranges


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g p ( ) g

(R) for ten samples of size 5 each. Draw mean & range

chart and comment on the state of control of the process.

Use the following control chart constants:

For n = sample size = 5

From Tables (Given)

A2 = 0.58, D3 = 0, D4 = 2.115

Sampleno.

1 2 3 4 5 6 7 8 9 10

X 43 49 37 44 45 37 51 46 43 47

R 5 6 5 7 7 4 8 6 4 6

Solution: Mean Chart (X Chart)


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X = x/10 = 442/10 = 44.2

R = R/10 = 58/10 = 5.8

3 control limits are

UCL(x) = x +A2R = 44.2+0.58 x 5.8 = 47.567

LCL(x) = X A2R = 44.2 0.58 x 5.8 = 40.836

Central line = x = 44.2


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Sample Numbers

Sample

mean

(X)

CL (44.2)

LC (40.83

UCL (47.5)

Range Chart


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3 control limits are:UCL(R) = D4R

= 2.115 x 5.8

= 12.267LCL (R) = D3R = 0 x 0.58

= 0

Central line = R = 5.8


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Q. From the following data, construct afraction defective chart (p chart)


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GroupNumber

SampleSize

No. ofDefective

s1 32 2

2 32 3

3 50 34 50 2

5 32 1

6 80 4

7 50 28 50 0

9 32 2

10 32 1


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Group Number(Group Number)

Fraction Defective (p)

1 2/32=0.0625

2 3/32=0.0940


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3 3/50=0.0600

4 2/50=0.04005 1/32=0.0300

6 4/80=0.0500

7 2/50=0.0400

8 0/50=0.0000

9 2/32=0.062510 1/32=0.0300

presentation1 (vpa) tqm

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