lecture5 mme3110 sem1 1112-1 qc in metrology [compatibility mode]

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Metrology and Measurement

Systems (MME 3110)

Semester 1, 2011-2012

Lecture 5

Quality assurance in metrology:Calibration, Procedures and Requirements



ISO quality systems as applied

to en ineerin metrolo



Introduction

Calibration Standards General approach to quality systems

ISO 9000 Quality Standards* ISO 9000: Quality Management and Quality Assurance

Standards Guidelines* ISO 9001: ualit S stems- ualit Assurance in

Contents

Design, Development, Production, Installation andServicing Functions

* ISO 9002: Quality Systems - Quality Assurance inProduction, Installation and Servicing Functions

* ISO 9003: Quality Systems - Quality Assurance in FinalInspection and Test Functions* ISO 9004: Quality management and quality system

elements

ISO 14000:Standards for environmental management Systems



Introduction

Accuracy in measurements is mandatory

To achieve this accuracy, calibration of theinstruments used to obtain measurements

frequency.

Measurements related to product quality arean important part of quality control systems.



Introduction

The ISO 9000 series of standards has been

established that provide procedures forensuring that an effective quality system,which meets customers' needs and is

maintained.



Introduction

Quality Assurance - Main factor in determiningwhether a company succeeds or fails is thequality in the goods and services that it provides

Competition in the market-place is intense andinternational.

quality control has therefore become of vitalimportance.

Hence need for companies to implement soundand effective quality control and quality assurancesystems for measurements -Calibration



Measurement must be of high quality i.e.

measurement ensures that process

variables within a manufacturing processare maintained within acceptable limitsand also checks that the final parameters

Calibration

of the product are within specifiedtolerances – how?

* using properly calibrated instruments

and transducers* all measurement errors are identified,

quantified and compensated for.



Calibration Calibration - comparing the output of

the process instrument being calibrated

against the output of a standardinstrument of known accuracy, when

applied to both instruments.

A few standards do exist to ensureeffective calibration process.



Standard LaboratoriesStandard LaboratoriesStandard LaboratoriesStandard Laboratories A few examples of organizations for accreditation

of standards laboratories include the following:

In the United Kingdom, appropriate NationalStandards Organization for validating StandardsLaboratories is the National Physical Laboratory.

Bureau of Standards

The UK Organization established a National

Measurement Accreditation Service (NAMAS)which monitors both instrument calibration andmechanical testing laboratories



Primary Reference StandardsPrimary Reference StandardsPrimary Reference StandardsPrimary Reference Standards

This describes the highest level of accuracy that isachievable in the measurement of any particular

physical quantity All items used in Standards Laboratories as secondary

reference standards have to be calibrated against

pr mary re erence stan ar s at appropr ate nterva s otime.

For e.g., the primary reference standard for dimension

measurement is defined by the wavelength of theorange-red line of Krypton light, and this can berealized in any laboratory equipped with an

interferometer.



Primary Reference StandardsPrimary Reference StandardsPrimary Reference StandardsPrimary Reference Standards

Primary reference standards, listed in Table below



TraceabilityTraceabilityTraceabilityTraceability

Calibration has achain-like structure inwhich everyinstrument in the

chain is calibratedagainst a moreaccurate instrumentimmediatel above it

in the chain, asshown in Figure.

The knowledge of thefull chain of theinstruments involvedin the procedure isknown as Traceability

Instrument Calibration chain



Typical TraceabilityTypical TraceabilityTypical TraceabilityTypical Traceability

Typical calibration chain for micrometers



WHAT IS ISO? A set of standards for quality management

and quality assurance systems developed bythe International Standard Organization

They provide a framework for quality systemdevelopment in all types of industries including

It is just purely a management system that willhelp us to run our business in a more organized

and systematic manner which will lead to a moreconsistent quality of the service that we deliverto our customers



ISO 9000 Quality standards

The term ISO 9000 is globally referred to as acomplete set of five documents which are

numbered ISO 9000 to ISO 9004. Collectively they are concerned with setting

out procedures that are designed to achieve

. They impose a requirement on suppliers of

goods and services to establish and maintainan effective, economical and demonstrablesystem, which ensures that what they supplyconforms to specified requirements.



ISO 9000 Quality standards contd. ISO 9000 -The first document in the set (ISO 9000 to

ISO 9004)-is not really a standard itself but consistsmerely of guidelines for selecting and using ISO 9001 toISO 9003.

The ISO 9001 to ISO 9003 documents are the actualquality assurance standards

,

document, which provides guidelines for developing andimplementing quality systems.

The ISO quality standards have now been adopted by

most countries around the world, but they are oftenpublished in individual countries with slightly differentprefixes or codes so that they harmonize with pre-existing national coding systems for standards.



ISO 9000: Quality Management and Quality Assurance

Standards Guidelines- Published in four separate parts

Part 1 (ISO 9000-1) gives general guidance aboutquality management and the implementation of quality

assurance procedures. Part 2 (ISO 9000-2) provides more detailed guidelines

on the implementation of ISO 9001-9003.

Part 3 (ISO 9000-3) gives specific guidance about theapplication of ISO 9001 where software either is theproduct or is Part of the product.

Part 4 (ISO 9000-4) gives guidance on developing andmanaging a programme which assures customersabout the reliability and maintainability of products.



ISO 9001:

ISO 9001 is the standard of most relevance tomanufacturing companies. It lays down

procedures for ensuring quality assurance inall aspects of manufacturing, including

installation and testing, servicing functions

The requirements to be satisfied can be readfrom the full standard (ISO 9001)



ISO 9002

ISO 9002: Quality Assurance in Production,Installation and Servicing Functions

ISO 9002 is a subset of ISO 9001 intendedf r m ni h nl r vi

manufacturing, installation and test function(i.e. no product design). It also applies tocompanies that only provide a servicefunction- e.g. specialized cleaning services)



ISO 9003

ISO 9001-9003 lay down procedures to be followedwhen selecting, using, calibrating, controlling andmaintaining measurement standards and measuring

equipment. A supplementary document, ISO 10012-1

(http://www.iso.ch/ ) defines the necessary procedures

in more detail and also gives some guidance aboutimplementation

ISO 9003: Quality Assurance in final Inspection and

Test Functions. It applies to companies that only provide a supply,

inspection and test service (i.e. no product

manufacture)



ISO 9004

ISO 9004 consisting of four parts, which

together provide further guidance on

developing and implementing qualitysystems

The general requirements of qualitysystem management, documentation,audits, costing, training and the control of

measurement and testing equipment arecovered



ISO 9004 contd.

Part 1 (ISO 9004-1) gives general guidelines.

Part 2 (ISO 9004-2) gives more specific

guidelines where a supplier is providing aservice.

-

guidelines where a supplier is providingprocessed materials.

Part 4 (ISO 9004-4) gives advice on how toimplement a system designed to achievecontinuous improvements in quality



ISO 14000 Standards for environmental

management systems The major difference between ISO 9000 and

14000 standards is in their application.

The ISO 9000 is concerned with quality ingoods manufactured and services provided.

ISO 14000 covers environmental concernsof air and water pollution, wasteminimization /disposal and good practice in

product use.



General approach to quality systems

For a quality control system to operatesuccessfully in a company, certainconditions have to be satisfied.

The procedures instituted must beorientated towards preventing quality

problems occurring, i.e. not being merefault detection-type systems



General approach to QA

When introducing quality control procedures,it’s very important that employees at all levelsin a company are aware of the reason for them,understand fully how to operate them, and co-

operate enthusiastically in implementing them

Although a quality control manager must beappointed to design and monitor quality control

systems, the control system is not a one-

person show. All personnel in a company mustbe encouraged to share in the duty of

maintaining good quality and take pride in it



General approach to QAs

Quality control procedures shouldevolve and develop over a period of

time. Regular review is necessary toensure that quality control procedurescontinue to be efficient and remain the

most appropriate as technologicaldevelopments take place

Reviews must also take changes inmarket forces into account and fullymonitor customer satisfaction, need and

expectations



Process Instrument CalibrationProcess Instrument CalibrationProcess Instrument CalibrationProcess Instrument Calibration Changes in instrument characteristics are

caused by factors like mechanical wear,and the effects of dirt, dust, fumes andchemicals in the o eratin environment.

Periodic recalibration is necessary becausethe characteristics of any measuringinstrument change over a period of time

and affect the relationship between theinput and output



Process Instrument CalibrationProcess Instrument CalibrationProcess Instrument CalibrationProcess Instrument Calibration

During calibration process, the instrumentis tested over its whole range by repeating

the comparison procedure for a range ofinputs

The instrument used as a standard forcalibration process must be kept solely for

calibration duties and it must never beused for other purposes



All instrument characteristics are affected tosome extent by environmental conditions,

and any parameters given in data sheetsonly apply for specified conditions


- ere ore, as ar as pract ca e, t esesame environmental conditions should be

reproduced during calibration procedures



For proper management of calibrationprocedures, it is important that the

performance of all calibration operations isassigned as the clear responsibility of just


.

Assigned person should have total controlover the calibration function, and be able

to limit access to the calibration laboratoryto designated approved personnel only




One of the clauses in ISO 9000 requiresthat all persons using calibration equipmentbe adequately trained and the training mustbe adequate and targeted at the particular

nee s o e ca ra on sys ems nvo ve




Over the longer term, the characteristics ofthe working standard will drift, mainly owing

to ageing effects in components within it.

quality-related measurements must becalibrated from time to time against astandard instrument (secondary referencestandard) of higher accuracy at appropriateintervals of time



Proper records should be maintained forcalibration procedures. A separate record

should be kept for every instrument in thefactory, whether it is in use or kept as a spare.This record should start b ivin a descri tion


of the instrument and then stating the requiredcalibration frequency

When the working standard instrument hasbeen calibrated by an authorized standards

laboratory, a calibration certificate will be issued



Documentation in workplace

This deals with the maintenance of

measurement systems and the operationof calibration procedures

It must ive a full descri tion of the

measurement requirements throughout theworkplace, the instruments used, thecalibration systems and procedures

operated



Documentation

Calibrate all measuring instruments underspecified environmental conditions so that their

measuring accuracy is known over the wholemeasurement range

characteristics under environmental conditionsdifferent from the calibration conditions

Establish measurement procedures whichminimize the effect of environmental conditionchanges on the measuring instruments



Documentation

Calculate the bounds of measurement error ofan instrument under normal operating

conditions Determine the rate of change of instrument

experimentation Hence to determine the frequency at which

instruments should be re-calibrated and the

maximum possible measurement error whenthe instrument has drifted furthest from itsspecification immediately before calibration



Documentation

Combine all instrument measurement errorlevels into a figure which expresses the

cumulative error level of the wholemeasurement process (where a measurement

instrument)

Document all measurement and calibrationprocedures

S



Summary

Quality must be ensured in measurement



THE END

lecture5 mme3110 sem1 1112-1 qc in metrology [compatibility mode]

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