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Quality Management – Prof. Schmitt Lecture 11

Quality and Information L 11 Page 0© WZL/IPT

© WZL/Fraunhofer IPT

Lecture Quality Management11 Quality and Information

Prof. Dr.-Ing. Robert Schmitt



Page 1© WZL/Fraunhofer IPT

ContentsPyramid of Knowledge

Quality Control Loops

CAQ - Computer Aided Quality Management

Introduction of CAQ Systems

Literature:Pfeifer, T.: Qualitätsmanagement Strategien, Methoden, Techniken; Carl Hanser Verlag; München, 2001,ISBN 3446215158 Pfeifer, T.: Quality Management Strategies, Methods, Techniques;Carl Hanser Verlag; München, 2002, ISBN 3446220038 Pfeifer, T.: Praxisbuch Qualitätsmanagement Aufgaben, Lösungswege, Ergebnisse; Carl HanserVerlag; München, 2001, ISBN 3446215085Masing, W.: Handbuch der Qualitätssicherung; Carl Hanser Verlag; München,1988, ISBN 3446175709 Erb, M.: Methodik zur modellgestützten Planung von CAQ-Investitionen; Shaker Verlag GmbH; 1996, ISBN 3826515900Mutz, M. u.a.: Marktspiegel CAQ-Systeme; Sondereinband - TÜV Rheinld.; Kln., 1998, ISBN 3824904578Platt, A.: Rechnergestütztes Qualitätsmanagement für Chargeprozesse in industriellen Dienstleistungsunternehmen; Verlag Dr. Kovac, 1998, ISBN 3860647520




Pyramid of Knowledge

Data

Information

Knowledge

Action

Signs

Syntax

Semantics (meaning)

Pragmatics (networking with context and know-how)

Decision

Data management

Information management

Knowledge management

Quelle: Erweiterung zu Davenport

Pyramid of KnowledgeThe signs build the bottom of the pyramid of knowledge. A sign is the smallest accessible data element. It can consist of numbers, letters or special signs.In combination with syntax, signs become data. Data consist of texts, pictures etc., which can be seen, measured and structured.With the help of information, relations between problems can be recognised. Thereby, informationhelps achieving the aim.Knowledge is more complex than information and data. It is a mixture of „structured experiences, ideals, context information and know-how, that builds a structural frame for the evaluation and integration of new experiences and information“.An action is the activity that follows a decision based on knowledge.




Pyramid of Knowledge - Example

Signs: 1, 0, S, G, W, T, R, E, N, I, D, N, H

The signs above mean „ wind strength 10“ by using the right syntax (in this case the order of the signs)

Data:

„Wind strength 10“ means: a thunderstorm appears.Information:

Experiences like „my boat can capsize“ are associated.Knowledge:

Activities like fixing the boat at the footbridge are derived.Action:











Types of Quality Control Loops

Control loop within a level

Control loopnear machines

Control loopsin machines

Operational level

Planning level

Management level

Steering level

Control loop between levels

QCL – Quality Control LoopThe picture shows a four-step company model, which demonstrates simultaneously the intra-corporate information-model and the Quality Control Loops in companies.- Management level: Defines corporate targets and derives company concepts- Planning level: Concepts are transformed in job instructions for execution (e.g. progress planning)- Steering level: Production orders are managed- Operative level: Concepts and strategies are transformed in real productsIn all loops, in a level and between levels, the pyramid of knowledge can be found. Within a level, the transformation of information happens within the specific fields of duty. Between levels, e.g. the whole company, the transformation of knowledge is based on the strategic aims of the company. E.g. the management level derives strategic procedures from the knowledge of the processes.




Benefits of Quality Control Loops

Management Level

Planning Level

Steering Level

Operative Level

Qua

lity

Dat

a B

ase

- Information about the quality levels in the company

- Rationalisation with quality aspects- Quality supported investment planning- ...

- Preventive maintenance- Procurement of machines- Product and production planning with focus onquality

- ...

- Technical and economical selection of suppliers- Assurance of data quality- Clarity of quality costs- ...

- Reduction of rejects- Reduction of processing times- ...

The advantage of Quality Control Loops at the different company levels can be described as followed:At the management level information about the quality ability of the company enable a rationalisation with quality aspects.The planning level gets information about preventive maintenance, production planning etc.Assurance of the data quality or transparency of quality related costs are relevant for the steering level.The reduction of rejects and processing times are examples for the advantages of the Quality Control Loops for the operative level.The information which are generated in the different levels establish the Quality Data Base. The information can be changed into knowledge through the combination of context and experience (pragmatics). Actions can be derived from the knowledge.




Model of a Quality Control Loop

Controlled system

Process Product

Manipulatedvariable• Process intervention• Analysis of tolerance• Change of construction

+

+

-

Target value/ requirement forquality

Control variable/ quality

-

Controller

Disturbance variable

7M

Quality Data Base

On-Line Off-LineSPC

PPL

...

FMEA

QFD

Audits

Model and Systematic of a Quality Control LoopTo illustrate the mode of operation of Quality Control Loops the basics of classical control loops will be used.The aim of a regulation is to retain specific parameters on predetermined set points. In technical practice, these parameters are mostly output variables of technical processes. Parameters that have to be regulated, should follow the change of set points as well as possible. Process-operating failures should not have any influence on the regulated parameters. The principle of a system of Quality Control Loops is shown in the picture. By comparing flow technology design with quality assurance, it becomes clear that, in general, the model of flow technology design is transmittable to quality assurance.Quality Management separates on-line and off-line regulators. While on-line regulators are attached closely to the production line (e.g. short-run error-logging), off-line regulators are utilised in indirect sectors (e.g. QFD, FMEA).In the picture disturbance variables are displayed as Ishikawa-diagram (fishbone diagram). They act unplanned on the controlled system.The disturbance variables are symbolically characterised as the „7M“ of Quality Management (mankind, material, machine, marginal conditions, measurability, management and method).The company-wide integration of quality assuring methods (On- and Off-Line) in Quality Control Loops allows the efficient and fast reaction on incidents in the company.Functional departments and processes can be defined as control paths of Quality Control Loops in the company. Thereby, it is a matter of the whole department, e.g. the construction or production, but also of several production areas such as preparation of a task schedule, drawing or production of a feature of a machine.Regulators do not take effect on these control paths with simple regulation mechanisms, but with methods of the preventive Quality Management.The number of possible regulation parameters rises with the span of the Quality Control Loop.The output of the Quality Control Loop, the disturbance variable, the controlled system and the controller will be integrated in the quality data bases.The classical control loop model has to be extended by an additional component, the Quality Data Base.




Example For a Machine-Oriented Quality Control Loop

SPC

CurrentVoltage...

Serigraphy Galvanisation Take a sample

• Analysis of control chart

• Identification of disturbance

• Detection of causes

• Turn off causes (correctsetting parameter of electroplating bath)

Check

X-K

arte

S-K

arte

In machine-based Quality Control Loops, the target variable is not identified until the product has already left the process. The results of a test or the occurrence of certain events then trigger the introduction of process-improving measures. Since it is frequently impossible to describe the correlation between target and manipulated variable unambiguously, the control process demands a considerable level of knowledge about the process and is usually conducted by experienced specialists. Approaches to automating control loops of this nature, for example, rely on the use of expert systems. SPC (Statistical Process Control), is an example of machine-based Quality Control Loops.The process of electroplating heated rear car windows is an example of this type of control loop. In a process which has been very much simplified, the mask for the heating wires is applied to the window in a screen printing operation, after which the window is electroplated. After the electroplating bath, samples are taken and the electrical resistance of the heating wires in the windows to be tested are measured. The average control card parameter x and the scatter or range R are then calculated on the basis of the measured values. The progression of the mean values (x) and ranges (R) provides the machine operators with clues to the possible influence of disturbance variables when they analyse the card. When disturbances are discovered, the process is stopped and the cause of the disturbance is determined. In the example outlined above, the settings for the electroplating bath had to be corrected due to a disturbance at time t1, and to the resultant exceeding of the upper action limit of the x value. To return the process to a stable state, the cause parameter (e.g. current intensity or voltage) should be reset. The adjustment is effected within the permissible manufacturing tolerances, ensuring that no rejects are produced, despite the fact that one of the intervention boundaries of the mean value was exceeded. If a control card is to be kept, considerable knowledge about process correlations is required in order to be able to react appropriately when disturbances occur. Therefore, it is advisable to document causes and measures in an appropriate form so that reactions are possible, when new disturbances occur in the future. It is particularly important to file this information so that it can be recalled swiftly and used by higher-level units.




Example For a Quality Control Loop in Quality Management

+

-

Target variable/quality requirements

-

+

Controlled variable/quality

+

-

Disturbance var.

7M

Disturbance var.

7M

Controlled systemProduction

process

Controlled systemConstruction

process

ControllerMethods

ofoff-line-qm

ControllerMethods

ofon-line-qm

7M

- Man- Machine- Material- Management- Measureability- Environement- Methode

Failure detection

Failure correction

The example shows a combination of multiple control paths. The production process and the construction process influence the control variable. The processes are the control path of the Quality Control Loop.The target variable is given by the quality standards which are defined in the quality planning.The manipulated variables are described through the unplanned and changing influence of the 7 M (mankind, material, machine, marginal conditions, measurability, management and method).The controller compares the controlled and target variables and generates the set values from the difference. The controller is equal to a QM-Method in the Quality Management.The set values affect the control path. On-line controllers directly affect the production process. Off-line controllers firstly affect the preliminary and downstream areas, and therefore, later on through constructional changes, the production process as well.




Imaginary Model of a Quality Data Base

Process data

Data aboutmanufacturing

equipment

Product data

Machine data- Tool data- Device data- ...

Production data- Cost centre data- Process data- ...

Machine capability- Testing tool history data- Maintenance data- ...

Process capability- Defects / Malfunction- Correction measures- ...

Inspection station data- Inspection device data- ...

Sampling system- Defect catalogue- Causes- Results- Measures

- Product Data- Characteristics ofconstruction

- Process plan data- ...

- Inspection data- Defect data- Quality characteristics- ...

- Defect mode- Main inspection plans- ...

Production dataMaster data History data

Quality data

The Quality Data BaseThe data base is divided in product data, maintenance equipment data and process data. Within these three sectors, production data, master data and history data are separated.Production data e.g. are characteristics of construction, machine data and production data.The Quality Data Base consists of a master data and a history data fraction.Master data are desired attributes whereas history data are measured actual values.The Quality Data Base can physically be realised by splitting into several data bases.











EDP – Electronic Data Processing - Systems in Companies

EDP-Enterprise Resource Planning (ERP)-Operating Data System(ODS)-Material Data System (MDS)-Computer Aided (CAx)

Financialmanagement

Material management

Human resource

management

Productionmanagement

Quality management

Project management

Customermanagement

CAQ Systems1. EDP-Systems in CompaniesIn companies different EDP-systems are used to support various demands in the different domains of a company.The following domains are being considered:- Financial management- Customer management- Project management- Production management- Personal management- Material management- Quality Management (QM)A so called CAQ-system (Computer Aided Quality) is used in the QM.




Computer Aided Quality Management

PPS: Production Planning and ControlCAD: Computer Aided DesignCAP: Computer Aided PlanningODS: Operating Data SystemMDS: Material Data SystemCNC: Computer Numerical ControlQuality Data Base

PPC CAPCAD

StatisticsBDE/MDE

CNC

Management level

Planning level

Control level

Operative level

Machine data

Inspection orderTest data

Evaluation

Component draw.

Master data

Quality control plan

Quality data

Production release

Control draft

NC-programs

CAQ

QM-policyQM-strategyQM-aims

Quality planningQuality controlling

Testing controlanalysis of measured values

Acquisition of measured values

2. CAQ – Computer Aided Quality ManagementA company organisation consists of many networked control loops which are inside the company organisation structure and the process organisation.The more complex the business processes in the company are, the more CAQ-systems are depended on the integration of other EDP-systems.The picture shows the interfaces to other information and communication systems, as well as the data exchange between the systems.




Development of CAQ

I = Inspection

Computer added tasks of quality inspection and testing

S = Security

Single computer-aided measures of quality assurance

M = Management

Integration of functions in planning and production, exchange with internal information systems

O = Organisation

Company-wide CIM-concept: e.g. Aachener QM-Model, continuously computer-aided process of improvement

Function-orientedResult-oriented Process-oriented

CA CA CA CA

Q(O)Q(M)

Q(S)Q (P)

Q(M)

Q(S)Q (P)

Q(S)Q (P)Q (P)

CAQ has developed from the result-oriented to the function-oriented right up to the process-oriented view.Out of a simple single computer aided measure of quality assurance became a company-wide CIM-concept (Computer Integrated Manufacturing) for a computer aided continuous improvement process.




CAQ – Function Model

Quality Function Deployment (QFD)Failure Mode and Effects Analysis

(FMEA)Design of Experiments (DOE)Gauge Management (PMM)

Quality planning Quality control

Inspection planTest data acquisitionTest data analysisTest data documentation SPC (Statistical Process Control)

Quality inspection

Organisationalrequirements & conditionsInform, control, adjustUser administrationDistribution of rights

IT-requirements and conditions

Data transferData storageData processingInternetThird-party system (machines, measuring device, Software)

Quality Data analysis (QDA)Quality based costsQ-AuditComplaint management

CAQ- Function ModelThe CAQ-function model consists of quality planning, IT-requirements and conditions, quality control, quality inspection and organisation requirements and conditions.




Example For a CAQ System – CAQ = QSYS

PMM

Gauge Management

PMM

Gauge Management

PPL

Inspection Planning

PPL

Inspection Planning

SPC

Statistic Process Control

SPC

Statistic Process Control

WE

Incoming inspection

WE

Incoming inspection

WA

Finished parts inspection

WA

Finished parts inspection

RQMS

Reclamation and Quality Cost Management

RQMS

Reclamation and Quality Cost Management

APQP

Advanced Product Quality Planning

APQP

Advanced Product Quality Planning

EMPB

Green Model Inspection Protocol

EMPB

Green Model Inspection Protocol

Netcom

Master data and inspection orders from ASCII file or outside-database

Netcom

Master data and inspection orders from ASCII file or outside-database

Toolcom

Loading inspection information and data from ASCII files (inspection protocol files)

Toolcom

Loading inspection information and data from ASCII files (inspection protocol files)

Data basedCAQ-System

Main

User administration master data

Main

User administration master data

FMEA

Failure Mode and Effects Analysis

FMEA

Failure Mode and Effects Analysis




Process-Oriented Quality Management in CAQProduct Data Management

Audit Management

Complaint management/CIP

Inspection tool management

Lot persecution

Design-FMEA

Product-FMEA

APQP APQP

Control station

Distributorappraisal

Incominginspection

Initial sampleinspection

Service-transaction

Finished partinspectionQFD

Initial sampleinspection

SPC-check

Quality inspection

Process-FMEA

Testplanning

DOECustomer to

innovation

Idea to

technology

Idea to

product

Process planning

Demand on

stockOrder to

cashProduct in

use

The picture demonstrates how modules of a CAQ-system can be integrated in the value adding chain.Single modules are continuously used, e.g. Product Data Management and Audit Management. Others are only implemented in special areas of the value adding chain, e.g. test planning and SPC.This depends on the process of each company as well as on their requirements and demands.




Computer Aid in Quality Management – Example Inspection Plan

Inspection data management

Inspection planning guideline

Insp

ectio

n pl

anni

ngIn

spec

tion

Insp

ectio

n da

ta p

roce

ssin

g

Inspection plan Measuring program

- Dynamises the scope ofinspection

- Identify critical points

Steps of inspection data processing:

Inspection data processing of large-batch production:

- Processing- Setting up codes- Recording- Describing

- Control charts- Examination of processcapability

Inspection data processingof simple-item and small-batch production:

- ABC evaluation analysis- Failure analysis

Inspectionplans

Inspectiondata

Inspection data processingin order to:

Inspectiontools

Standards specifi-cations

3. Example Inspection PlanThe inspection implementation is oriented on the demands of the inspection planning. The inspection results, which are based on the inspection implementation are documented in inspection records like actual value tables, measured value logs or documentation of failures.The duty of the inspection data analysis is the rating and aggregation of the inspection results to inspection conclusions. These are on one hand communicated as a decision guidance for the inspection planning to update the inspection effort and on the other hand it is communicated to the quality control to initiate quality-improving efforts.The drive to rationalise in quality testing and inspection is aimed at ensuring, that individual tasks in various areas of activity are performed more effectively (as a result of the automation of individual machining steps, for example ). Furthermore a continuous IT-related communication between the various areas should be ensured.There is evidence that the trend in testing is shifting away from acceptance tests towards in-process monitoring. As a result of the shift in emphasis towards on-going production, failures in the development can be detected and solved more swiftly. The objective is “controlled manufacturing”which, ideally, would help not producing any more rejects at all.




Functions of the Inspection Plan Generation1.Definiton of thehead data in theinspection plan

2.Selection of an inspectioncharacteristic

3.Specification of time of inspection

4.Specification of the degree of inspection

5.Specification of theplace of inspection

6.Specification of personnel forinspection

7.Selection of inspection tool

8.Specification of kind of inspection

9.Specification of text of inspect.

10.Specification of documentation of inspection

11.Specification of inspect. dataprocessing

12.Generatinginspectiongraphics

PPL

Text TextText TextText Text

PPLattributiv

variabel

?Skip lot?

3.1 Functions of the Inspection Plan GenerationFor the generation of an inspection plan e.g. inspection tools and characteristics are required. The modules which are regarded in the inspection plan should also be defined (e.g. finished parts inspection, incoming inspection, SPC...).The order to execute the inspection planning functions depends on the size of the company, organisational structure etc., but the determination of the inspection criteria is required for further actions.The guideline recommends that the following list of questions should be answered systematically for each selected test characteristic:- „what“ : Selection of test features- „when“: Determination of time of inspection planning- „how“: Determination of inspection manner- „how much“: Determination of test range- „where/who“: Determination of test location/personnel- „with what“: Selection of inspection tools

Determination of inspection textDetermination of inspection documentationDetermination of inspection data processing




Inspection Planning As an Example of CAQ = QSYSInput togenerate inspectionplans:•Product

•Inspection tool

•Characteristic

•Defect

Input togenerate inspectionplans:•Product

•Inspection tool

•Characteristic

•Defect

Inspectionplan (IP)- Generate- Edit

for modules:- WE- WA- SPC- EMPB

- Inspectionstationassigning

IP- Save

Product IP- Product nr.- Prod.

designation-Rooting nr.

Group IP:- IP nr.- IP designation

Special IP:- IP nr.- IP designation

Inspectionstep- Paste- Edit

- Delete

Inspection stepdefining as:- Variable,- Attributive,- Visualcharacteristic

Acceptdefinedinspection step

- Generatinginspection order

- Acquisition


- Acquisition


- Acquisition


- Acquisition

Inspection planning

WA WE SPC EMPB

A further objective which is aimed with the use of computers in test planning, is to record, evaluate and use quality-determining data systematically in order to ensure product and process quality and reduce time and costs. Test planning is one of the basic elements of any CAQ system. It is one of the classical CAQ functions, alongside test control, test data collection and test data evaluation. The function of the test planning module is to provide the planner with as much support as possible in the individual machining steps, as well as ensuring a clearly structured approach, all information must be easily and swiftly available.




Functions of the CAQ – Supported Generation of Test Data

Identificationof inspector

Choose insp. order

Choose insp. characteristic

Transfer and display test data

Correct test data

12,5 13

sxf Σ=

Calculate values of assembledcharacteristics

n.i.o.-output:detect type of errorand reason

n.i.o.-output:decision about furtherutilization

generation of test data

n.i.o.: not in order

The recorded test data are stored and processed by the CAQ system. They can be compressed and evaluated on the basis of many different criteria by using statistical techniques. The test data can be evaluated, for example, in an order-, batch-, part- or characteristic-oriented operation encompassing various suppliers, machines and periods of time (e.g. shift evaluations).Evaluations typically supported by CAQ systems, include linear diagrams of the measured values (original value cards) frequency distributions (histograms), statistical characteristic values (mean values, standard deviations, etc.), information about rejects and rework, failure and control charts and distribution tests.




Examples for Computer Aid

￭Article inspection plan (=single inspection plan);

Article specifical inspection plan based on article number, which is being loaded of the article master data – with maintenance sequence

Test planning: Generation of test data (variable characteristics):

- Inspection planning- Inspection-data acquisition (variable criteria)




Example - FMEA

4. Further Examples for Computer AidExample FMEA




Example – House of Quality

Example QFD











CAQ Iceberg

ComplexityCAQ Support Availability of newmodules

Companygrowth

Time forimplementation

InternalIT-Support Reliability Language

optionsInterfacesupport

Acceptability Product

Training Needs

Investment

5. Introduction of a CAQ-SystemThe following points must be regarded during the introduction of a CAQ-system:- detailed and step-by-step planning of the recommendations- definition of the interfaces to other IT-systems, machines, measurement equipment and divisions - illustration of the „manual“ sequences of the QM organisation in the CAQ-system- qualification of the employees- continuous enhancement of the QM-process and CAQ-systemThe aim of the introduction is to bring the system step-by-step in further-reaching areas of the company, increasing the effectiveness and the efficiency of the CAQ application continuously.




Failures During the CAQ-Introduction

0 20 40 60 80 100

Wrong philosophy

System changing instead of optimising

Lack of teaching the users

No testing of the processes

Wrong economising by implementation

Failed optimising

Lack of project management

Failure by interpretation of “standards"

High system complexity

Inefficient project processing

Missing cost benefit analysis

The failures of the software-system introduction mainly are missing cost benefit analysis and inefficient project processing.




Stepwise Procedure When Choosing a CAQ-SoftwareStep 1:

Process analysis

Step 2:Interface analysis

Step 3:Target concept

Step 4:Market analysis/

software selection

Step 5:Integration

BDE-SystemPPS-System

CAQ-SystemMesssysteme

CAQDatenbank

Qualitätsprüfung

Qualitätsplanung

Informationstechnische Voraussetzungen

OrganisatorischeVoraussetzungen

Qualitätslenkung

0,00 Euro

100.000,00 Euro

200.000,00 Euro

300.000,00 Euro

400.000,00 Euro

500.000,00 Euro

600.000,00 Euro

700.000,00 Euro

Anbieter 1 Anbieter 2 Anbieter 3 Anbieter 4

1 Jahr5 Jahre10 Jahre

Prozessschritt

Prozessschritt

Abfrage AbfrageAbfrage Abfrage

Prozessschritt SubprozessProzessschritt Subprozess

Start

Ende

Output

Output

Output

Output

Input

Input

Input

Input

In the first step the process analysis is used to create a company specific process map. Therefore the main processes must be identified. Afterwards, the main processes will be reduced to sub processes. These sub processes can be subdivided in the following steps and input and output information can be identified. In the second step the interfaces between hardware and software components as well as the interfaces between the employees and the divisions are identified using the input and output information of the main and sub processes. This is important for being able to realise the information flow to the right division at the right time.The target concept (step 3) defines the user demands of handling the system. It also describes visions and strategies for the future. Further visions and strategies are defined in the target concept. The current status and the target concept are documented in a requirement specification.




Explanation of the Stepwise Procedure

step 1:Process analysis

step 2: Interface analysis

step 3:Target concept

step4:Market analysis/

software selection

step 5:Integration

Company specificprocesses

(actual state analysis)

Requirements andvisions

Decision forsupplier

Specification(requirement)

With the specification (requirement) and market analysis (step 4) a CAQ software can be selected which is able to show the process map of the company. First, a wide selection is made with a critical catalogue. After that, the different suppliers can be analysed by their module and system properties. Through correlation between the supplier and the processes on the basis of the module and system properties a close-pitch selection is made. In workshops with the selected suppliers, the supplier who is able to show the best process map will be chosen.The integration is the fifth and last step, which must be executed in close co-operation with the supplier, because he has got the knowledge from further projects about how much time is needed to integrate all interfaces.

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