Weld Quality: The Role of Computers documents the proceedings of the International Conference on Improved Weldment Control with Special Reference to Computer Technology, held in Vienna, Austria, 4-5 July 1988, under the auspices of the International Institute of Welding. The topics of the four sessions are: (I) Design, Calculation and Prediction Models For Metallurgical Processes/Conception; (II) Inspection and In-Service Monitoring; (III) Fabrication, Quality Assurance; and (IV) Expert Systems, Data Banks and Future Possibilities. Session I includes papers on the use of computer technology to establish the quality of the welded joints; computer-aided design system for design of fillet welds with optimum shape; and the use of numerical simulation software for predetermination and optimization of the mechanical resistance of brazed joints. The papers in Session II cover topics such as acoustic emission testing; eddy current inspection system for weld testing; and holographic imaging of weld cracks. Session III includes papers on a computer controlled friction welding system and a CAQ-system for welding workshops. The presentations in Session IV include an approach for writing conventional software and expert systems for welding engineers and an expert system for robotic welding.

PrefaceForewordList of PapersSession I Design, Calculation and Prediction Models for Metallurgical Processes I.1 Improved Weld Quality with Special Reference to Computer Technology. The Design Function Abstract Introduction The Process of Design Sources of Uncertainty in Experimental Results Sources of Uncertainty in Practice Provision of Design Data by Computer Technology Expert Systems in Design Conclusion References I.2 Computer-Aided Design System for Fillet Welded Joints Introduction Conclusions References I.3 Design Stress for Plate and Shell Welded Connections: Concept, Definition and Improvement Abstract Keywords Introduction Stress Analysis Stress Concentration and Hot Spot Stress Computer, Numerical Analysis and Design Stress Conclusion References I.4 Optimization by Numerical Simulation of the Brazed Joint's Mechanical Resistance Abstract Keywords I - Data II - Method of Analysis III - Brazed Assembly in Plane Stresses: Extremely Thin Joint IV - Asymmetrical, Hypothesis, and Data V - Brazed Joint Where the Joint is Parallel to the Stresses I.5 Mathematical Description of HAZ Behavior of Low-Alloyed Structural Steels Abstract Keywords Introduction HAZ-Simulation Studies on Low-Alloyed Steel Type 19MnA16 HAZ-Description Using Parametric Equations Mathematic Modeling of the Microstructural Changes in the HAZ Discussion and Conclusions References I.6 Weld Formation Simulation and Optimization of Stainless Steel Automatic Argon Tungsten Arc Welding Conditions Conclusions References I.7 A Computer Model for Estimating the Risk of Sensitization When Welding Stainless (18/8) Steels Abstract Keywords Introduction Heat Transfer during Welding Sensitization Damage Parameter Computer Solution and Results References I.8 The Design of Submerged Arc Weld Deposits for High-Strength Steels Abstract Keywords Introduction Experimental Results and Discussion Conclusions Acknowledgments ReferencesSession II Inspection and in-Service Monitoring II.1 Acoustic Emission Testing (AET) Experience with an Integral Nondestructive Inspection Method for Pressure Vessels Abstract Keywords Introduction Inspection System Application of Technology From TÜV Vienna Performed Tests Conclusion References II.2 Computer Aided Design of Eddy Current Weld Inspection, Optimization of a Multifrequency Approach Abstract Keywords Introduction 2. Principle of the Eddy Current Method 3. Eddy Current Procedures References II.3 Holographic Imaging of Cracks in Welds Abstract Keywords Introduction The Concept of Holography: Backpropagation of Scalar Wavefields Holographic Imaging with Elastic Waves References II.4 Robot for Real Time Radiographic Inspection of Circonferential Weld with Computer Processing of the Whole System Abstract Introduction Inconvénients de la Radiographie Conventionnelle Contraintes Liees a l'Implantation de la Radioscopie sur Barge de Pose Description du Systeme de Controle ResultatsSession III Fabrication, Quality Assurance III.1 Development of a Microprocessor-Based System to Determine Resistance-Spot-Weldability and Perform Electrode-Life-Tests Automatically Abstract Key Words Introduction Initial Results Goals and Future Prospects III.2 Friction Welding - Computer-Aided Quality Inspection Abstract Keywords Introduction Computer Controlled Friction Welding Principles of Computer-Aided Process Monitoring Experimentals Conclusion References III.3 Support of Quality Assurance Activities and Weld Inspection by Means of Computer-Aided Data Acquisition and Documentation Abstract Keywords Introduction Possibilities of Computer-Aided Data Acquisition (CAQ) CAQ in the Organization of Non-Automated NDE Weld Inspection CAQ in the Production of Longitudinally Welded Stainless Steel TubesSession IV Expert Systems, Data Banks and Future Possibilities IV.1 The Welding Institute Approach to Writing Information Software for Welding Engineers Summary Keywords Introduction Software Packages Welderqual Weldspec Weldvol and Weldcost Preheat Expert Systems Expert Systems in Welding Future Work References IV.2 Base de Données Pour le Soudage Adaptatif en MIG Pulsé Resume Mots Cles Introduction Conditions Experimentales Methodologie de Constitution de la Base de Données Les Resultats Experimentaux Discussion sur les Resultats Conclusion References Remerciements IV.3 Experimental Design System for Solving the Problems of Welding Operational Parameters Optimization IV.4 Expert System Improves the Robotic Welding Procedure Abstract Keywords Introduction Possible Replacement of Welder's Tasks by Artificial Intelligence Description of the Welding Expert System The Expert System in the Welding Control Loop Future Developments Conclusions References IV.5 Welding Expert System: From the Welsys Experience Abstract Keywords Introduction Motivation Aims of the Project Organization First Year Activities What We Learned from the First Year Activity Second Year Activities What We Learned from the Second Year Activities What We Suggest from this Experience References IV.6 Weldex: An Expert System for Designers Abstract Keywords Introduction Artificial Intelligence Approach for Welding Technology System Architecture and Functional Design of "Weldex" System Conclusion ReferencesPosters Evaluation of Residual Stress States in Welded Parts - Using Ultrasonic Techniques Abstract Keywords What are the Major Difficulties? - What Has Been Achieved? References A CAD/CAM Tool for Structural Welding Abstract Keywords Introduction Computer-Aided Design System for Estimation of Fatigue Life of Welded Joints under Low-Cycle Loading References Comparison of Methods for the Description of the Thermal Cycle during Welding References Microcomputer Control of Resistance Welding Quality Abstract Keywords Introduction Vöz-M1 Control System References Self-Tuning Regulator for the Selected MAG Technology Process Abstract Keywords Foregoing Approach to MAG Process Control New Approach to Process Control Characteristics of the Selected MAG Technology Conclusions References "Synchronous Welding", an Automatic Technique for MIG Welding Abstract Keywords Introduction Principle Characteristics of System Implications Computer Control of Welding Parameters for Improvement of Weld Quality Abstract Keywords Introduction Experimental Discussion References Adaptive Control of MIG/MAG Welding - Feedback System for Weld Penetration Control Abstract Keywords Adaptive Control of Pulse MIG/MAG Welding Feedback Control of Weld Penetration (Pan, 1987b) Reference HPS - A High-Resolution Process-Orientated Seam Tracking System for In-Production Quality Assurance Abstract Keywords Introduction The Seam Tracking System "HPS" Off-line Mobile Robot for Welding of Horizontal Fillets in Girder Structures Automation in the Welding of Large Framed Cylinders Abstract Keywords Introduction Seam Tracking System Control Synchronous Welding Summary References Recent Seam Tracking Equipment Development for Electron Beam Welding Abstract Keywords Introduction New Detector Design Seam Tracking System References S.A.O. MIG-MAG: Prise en Compte des Phénomènes de Transfert D'arc Resume Mots Cles Introduction Description et Fonctionnement du Systeme Exemples d'Application Conclusion The Development of a Microcomputer-Based Control System of the Machine for Ultra Thin Sheets Welding Abstract Keywords Introduction Constitution and Function of the Control System Software Design and Debugging Elimination of the HF Interference Conclusions References Adjustment of Model of Arc Sensor for Adaptive Welding Robot References Development of an Automated Process Control for Mechanized Underwater Welding Abstract Keywords Introduction Description Mode of Operation Preliminary Experiments Nondestructive Residual Stress and Hardness Evaluation at Weldments by Means of 3MA (Micromagnetic, Multiparameter, Microstructure and Stress Analysis) Abstract Keywords 3MA Testing Unit. Theorie of Operation What Has Been Achieved? Difficulties References Alok-an Automated ut-System with Microprocessor Controlled Data Acquisition, Signal Processing and Computer Aided Defect Reconstruction - Applications in Weld Inspection Abstract Keywords Introduction Data Acquisition and Compression Data Evaluation Polyscope: Measuring System Developed for the Characterization of Weld Defects Abstract Introduction Materiel Mis en Oeuvre et Logiciels Fonctionnement Conclusion References Quality Monitoring and Control System for Resistance Spot Welding Process Abstract Keywords Instruction System Hardware System Software System Functions Experiments for Welding Procedures Contrôle de la Qualité en Temps Réel dans la Domaine du Soudage par Résistance Resume Mots Cles Introduction 1) Causes de "Non Qualite" 2) Moyens de Maintenir un Niveau de Qualite Acceptable 3) Principe de Controle de Qualite en Temps Reel 4) Les Applications en Production 5) Techniques Auto-Adaptatives, Qualite et Limite Ultrasonic Weld Inspection with Synthetic Aperture Focusing Techniques (SAFT) Abstract Keywords Introduction Test Facilities Experiments Expert System Welda: A Welding Design Advisor for Trial Manufacture Abstract Keywords Outline of the System Rules and Control Knowledge-Based Systems for Flaw Assessment Abstract Keywords Introduction A Text Animator for the New PD 6493 Charpy/Fracture Toughness Correlations for Ferritic Steels Discussion Investigation of Potential Application of Television in Microprocessor Systems for Consumable-Electrode Arc Welding Control Conclusions A New Type of TIG Welding Power Source with Artificial Intelligence Abstract Study on Real Time Quality Control of Resistance Spot WeldingAuthor IndexSubject Index