JF608: Quality Control - Unit 2

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UNIT 2- UNIT 2- BASIC QUALITY CONCEPT

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LOGOOUTLINEOUTLINE

Introduction

Definition of Quality

Zero Defect

Customer

Quality Associated Terms and Concepts

Inspection

Sampling

SPC vs Acceptance Sampling

LOGOINTRODUCTIONINTRODUCTION an essential factor to be considered in every

product or services. without adequate quality, it is not possible to

compete in the market. the future of an industry is driven by customers. at present industries are facing the following

challenges : increasing demands of customers increasing competition technological changes law becoming powerful

LOGODEFINITION OF QUALITY Quality is not merely the goodness or otherwise of a

finished product but it is the ultimate objective of the company and it is what customers expect from a product.

Some definitions of quality have been given Conformance to specifications and standards. Fitness of use. Productivity, competitive costs, timely delivery and total

customer satisfaction. Hence a definition of quality is the totality of features he totality of features

and characteristics of a product or service that and characteristics of a product or service that bears on its ability to satisfy stated or implied bears on its ability to satisfy stated or implied needs.needs.

LOGODEFINITION OF QUALITY Hence a quality product should meet the following

requirements Quality raw material should be used. Quality parts should be used. Assemblies should be of good quality. Should adopt quality process and processing

conditions. Should give high reliability. Should be aesthetic. Should conform to standards. Quality services.

LOGODEFINITION OF QUALITY Quality is quantifed as shown :

Where;

Q = quality

P = performance

E = expectations

If Q > 1.0, it implies that the customer has a good feeling about the product or service.

EPQ

LOGODIMENSIONS OF QUALITY

1. Performance

2. Features

3. Conformance

4. Reliability

5. Durability

6. Service

7. Response

8. Asthetics

9. Reputation

LOGOZERO DEFECT

a defect refers to any unwarranted deviation of physical entity or a process.

a product or service without the defect that can be seen.

LOGOZERO DEFECT

Why is “Zero Defects” an Important Concept?

Maintain Customer Satisfaction & Loyalty

Happy Customers mean more sales!

LOGOZERO DEFECT

Why is “Zero Defects” an Important Concept?

COST

There is always a cost associated with

manufacturing defects!

LOGOZERO DEFECT

Costs of Defects ?

Does it cost more to make processes better ? NO

Making processes better leads to reducedRework

Scrap

Warranty costs

Inspection costs

LOGOZERO DEFECT

1-10-100 Rule

The 1-10-100 rule states that as a product or service moves through the production system, the cost of correcting an error multiplies by 10.

Activity Cost

Order entered correctly $ 1

Error detected in billing $ 10

Error detected by customer $ 100

Dissatisfied customer shares the experience with others the costs is

$1000

LOGOCUSTOMER

customer satisfaction has become a measure of quality.

an organisation’s success depends largely on its customers.

satisfied customers will automatically contribute towards increasing the profit.

customer satisfaction is the goal of TQM.

LOGOCUSTOMER

Who are called CUSTOMERS ?

As anyone who receives that which is product or service by the individual or organisation that has

value

LOGO

TYPES OF

CUSTOMERS

CUSTOMER

EXTERNALCUSTOMERS

INTERNALCUSTOMERS

LOGOEXTERNAL CUSTOMER

exist outside the organisation purhase the product / service of the

organisation

LOGOINTERNAL CUSTOMER

exist inside the organisation. the end users of the organisation’s

product / services.

LOGOImportance of Quality to Customer

customers are retained by the organisation for a longer period.

customers recommend the product / services of the organisation to other.

it costs more to attract a new customer than in retaining an existing one.

organisations can take up their profits (25 – 125%) by retaining just 5% more of their exixting customers.

LOGOQuality Associated Terms

Quality Control (QC)

A system of routine technical activities, to measure and control the quality of the inventory as it is being

developed


Quality Assurance (QA)

Aan activities include a planned system of review procedures conducted by personnel not directly

involved in the inventory compilation/development process.


QC vs QAQA QC

Focus on:

QA aims to prevent defects with a focus on the process used to make the product. It is a proactive quality process.

QC aims to identify defects in the finished product. Quality control, therefore, is a reactive process.

Goal:

The goal of QA is to improve development and test processes so that defects do not arise when the product is being developed.

The goal of QC is to identify defects after a product is developed and before it's released.


Total Quality Management (TQM)A structured system for satisfying internal and

external customers and suppliers by integrating the business environment, continuous improvement,

and breakthroughs with development, improvement, and maintenance cycles while changing

organizational culture.


Concepts of TQM1. Commitment.2. Customer Satisfaction.3. Participation By All.4. Process Measurements.5. Continuous Improvements.6. Problem Identification.7. Alignment Of Organisational Objectives &

Individual Attitudes.8. Personal Accountability.9. Personal Development.


Continuous ImprovementA quality philosophy that assumes further

improvements are always possible and that processes should be continuously re-evaluated and

improvements implemented.


Continuous Improvement Represents continual improvement Represents continual improvement

of all processes of all processes

Involves all operations and work Involves all operations and work centers including suppliers and centers including suppliers and customerscustomersPeople, Equipment, Materials, People, Equipment, Materials,

ProceduresProcedures


Shewhart’s PDCA ModelShewhart’s PDCA Model

2. DoTest the

plan

3. CheckIs the plan working?

4. ActImplement

the plan

1.PlanIdentify the

improvement and make a plan


Six Sigma

A highly disciplined process that helps a company focus on developing and delivering near-perfect

products and services.


Six Sigma

Originally developed by Motorola, Six Originally developed by Motorola, Six Sigma refers to an extremely high Sigma refers to an extremely high measure of process capabilitymeasure of process capability

A Six Sigma capable process will A Six Sigma capable process will return no more than 3.4 defects per return no more than 3.4 defects per million operations (DPMO)million operations (DPMO)

Highly structured approach to process Highly structured approach to process improvementimprovement


Six Sigma

1.1. Define critical outputs Define critical outputs and identify gaps for and identify gaps for improvementimprovement

2.2. Measure the work and Measure the work and collect process datacollect process data

3.3. Analyze the dataAnalyze the data

4.4. Improve the processImprove the process

5.5. Control the new process to Control the new process to make sure new performance is make sure new performance is maintainedmaintained

DMAIC ApproachDMAIC Approach


Six Sigma Implementation Emphasize DPMO as a standard metricEmphasize DPMO as a standard metric Provide extensive trainingProvide extensive training Focus on corporate sponsor support Focus on corporate sponsor support

(Champions)(Champions) Create qualified process improvement Create qualified process improvement

experts (Black Belts, Green Belts, etc.)experts (Black Belts, Green Belts, etc.) Set stretch objectivesSet stretch objectives

This cannot be accomplished without a major commitment from top level management

LOGOINSPECTION Method to identify problems and correct

them early in the development lifecycle. Involves examining items to see if an item is

good or defective.

LOGOINSPECTION

Purpose of Inspection1. To distinguish good lots from bad lots.2. To distinguish good pieces from bad pieces.3. To determine if the process is changing.4. To determine if the process is approaching the

specification limits.5. To rate quality of product.6. To rate accuracy of inspectors.7. To measure the precision of the measuring

instrument.8. To secure products – design information.9. To measure process capability.

LOGOINSPECTION

When and Where to InspectWhen and Where to Inspect1. At the supplier’s plant while the supplier is

producing2. At your facility upon receipt of goods from the

supplier3. Before costly or irreversible processes4. During the step-by-step production processes5. When production or service is complete6. Before delivery from your facility7. At the point of customer contact

LOGOINSPECTION

Method Of Inspection100% SAMPLING

1. Involve careful inspection in detail of quality at each strategic point or stage of manufacture.

2. Requires more number of inspectors and hence it is a costly method.

3. Suitable only when a small number of pieces are there or a very high degree of quality is required.

4. Example : Jet engines, Aircraft, Medical and Scientific equipment.

1. Randomly selected samples are inspected.

2. Samples taken from different batches of products are representatives.

3. If the sample prove defective, the entire concerned is to be rejected or recovered.

4. Sampling inspection is cheaper and quicker because it requires less number of Inspectors.

5. Example : Electrical bulbs, radio bulbs, washing machine etc.

LOGOSAMPLING

sampling is a process that helps to determine whether to accept or reject

the sample being observed

LOGOSAMPLING

Why sample taken for inspection?

Economical and take less time Less handling damage Fewer inspectors Applicability to destructive testing Entire lot rejection (motivation for

improvement) Reduce the amount of inspection error

LOGOSPC vs ACCEPTANCE SAMPLING

SPC ACCEPTANCE SAMPLING

1.Provides near real-time monitoring of the process.

1.Ignores the process and focuses exclusively on the output after it has been produced.

2.Sampling to determine if the process is within acceptable limits.

2.Sampling to accept or reject the immediate lot of product at hand.

LOGO

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JF608: Quality Control - Unit 2

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