ARC WELDING Edited by Wladislav Sudnik Arc Welding Edited by Wladislav Sudnik Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2011 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work. Any republication, referencing or personal use of the work must explicitly identify the original source. As for readers, this license allows users to download, copy and build upon published chapters even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book. Publishing Process Manager Marija Radja Technical Editor Teodora Smiljanic Cover Designer InTech Design Team Image Copyright pmakin, 2011. DepositPhotos First published December, 2011 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from orders@intechweb.org Arc Welding, Edited by Wladislav Sudnik p. cm. ISBN 978-953-307-642-3 free online editions of InTech Books and Journals can be found at www.intechopen.com Contents Preface IX Part 1 Arc Welding Technology 1 Chapter 1 Hardfacing by Plasma Transferred Arc Process 3 Víctor Vergara Díaz, Jair Carlos Dutra and Ana Sofia Climaco D'Oliveira Chapter 2 Fusion Welding with Indirect Electric Arc 20 Rafael García, Víctor-Hugo López, Constantino Natividad, Ricardo-Rafael Ambriz and Melchor Salazar Part 2 Arc Welding Automation 45 Chapter 3 Arc Welding Automation 47 Eduardo José Lima II and Alexandre Queiroz Bracarense Chapter 4 WHI Formula as a New Criterion in Automatic Pipeline GMAW Process 71 Alireza Doodman Tipi and Fatemeh Sahraei Chapter 5 Sensors for Quality Control in Welding 81 Sadek C. Absi Alfaro Part 3 Weldability of Metals and Alloys 107 Chapter 6 Weldability of Iron Based Powder Metal Alloys Using Pulsed GTAW Process 109 Edmilson Otoni Correa Chapter 7 Assessment of Stress Corrosion Cracking on Pipeline Steels Weldments Used in the Petroleum Industry by Slow Strain Rate Tests 127 A. Contreras, M. Salazar, A. Albiter, R. Galván and O. Vega VI Contents Chapter 8 Evaluation of the Shielding Gas Influence on the Weldability of Ferritic Stainless Steel 151 Demostenes Ferreira Filho, Ruham Pablo Reis and Valtair Antonio Ferraresi Chapter 9 Corrosion Fatigue Behaviour of Aluminium 5083-H111 Welded Using Gas Metal Arc Welding Method 177 Kalenda Mutombo and Madeleine du Toit Part 4 Mechanisms, Models, and Measurements of Arc Welding 219 Chapter 10 The Mechanism of Undercut Formation and High Speed Welding Technology 221 Zhenyang Lu and Pengfei Huang Chapter 11 Physical Mechanisms and Mathematical Models of Bead Defects Formation During Arc Welding 243 Wladislav Sudnik Chapter 12 Using Solid State Calorimetry for Measuring Gas Metal Arc Welding Efficiency 265 Stephan Egerland and Paul Colegrove Chapter 13 Chemical and Physical Properties of Fluxes for SAW of Low-Carbon Steels 281 Ana Ma. Paniagua-Mercado and Victor M. Lopez-Hirata Chapter 14 Arc Welding Health Effects, Fume Formation Mechanisms, and Characterization Methods 299 Matthew Gonser and Theodore Hogan Preface Ever since the invention of arc technology in 1870s and it's early use for welding lead during the manufacture of lead-acid batteries, advances in arc welding throughout the twentieth and twenty-first centuries have seen this form of processing applied to a range of industries and progress to become one of the most effective techniques in metals and alloys joining. The objective of this book is to introduce relatively established methodologies and techniques which have been studied, developed and applied in industries or researches. State-of-the-art development aimed at improving technologies will be presented covering topics such as weldability, technology, automation, modelling, and measurement. This book also seeks to provide effective solutions to various applications for engineers and researchers who are interested in arc material processing. This book is divided into 4 independent chapters corresponding to recent advances in this field. The editor expresses thankfulness to all authors for the presented materials and their timely design, and also to the technical editor and to the book manager Mrs. Marija Radja - for the big work on preparation and the edition of this book. Editor Prof. Dr. Wladislav Sudnik R & E Center ‘Computer Hi-Tech in Materials Joining‘ Welding Department Tula State University, Russian Federation [...]... plasma arc in a convergent form The gas used for this purpose is generally argon 4 Arc Welding Electrode Plasma gas flow Powder Shield gas Constrictor nozzle Plasma arc Wire Substrate PTA PROCESS PAW PROCESS Fig 1 Comparison of Plasma Transferred Arc processes PTA and PAW Given that the tungsten electrode lies within the constrictor nozzle of the welding torch, it is difficult to open the arc by contact,... in alloys, respectively Fig 2b-c illustrates the difference between the indirect electric arc and the traditional electric arc welding processes In the majority of the electric arc welding processes, the electric arc is established between the electrode and the base metal The high energy developed by the electric arc is in direct contact with base metal and the forces generated in the weld pool affect... material Stellite 6 in the form of steel (BT-906T) 10 Arc Welding PTA Process Welding current Welding speed Plasma gas flow rate Shield gas Carrier gas Feed rate Constrictor nozzle diameter/ convergence angle Nozzle to workpiece distance Setback PAW Process Wire diameter (tubular) Wire speed Deposition rate Constrictor nozzle diameter Welding current Welding speed Plasma gas flow rate Shield gas Feed... to the conventional practice of fusion welding An overview of the findings and benefits observed in different materials as well as the evolution of the original idea throughout ten years of research are provided 2 Overview of the IEA welding process The indirect electric arc (IEA) technique is a novel welding process that has been successfully used to join MMCs (Garcia et al, 2002a, 2002b, 2003) It is... plasma transferred arc welding process which employs the filler metal in wire form is known as Plasma Arc Welding (PAW) while that which employs powder filler material is generally referred to as Plasma Transferred Arc (PTA), Dai et al., 2008 The PTA process can be considered a derivation of the PAW process The similarities between the two processes can be observed in Figure 1 Both welding processes... few days In response to the problematic issue of welding MMCs, the idea of the indirect electric arc was conceived (Garcia et al 2002) with the metal inert gas (MIG) welding process in order to overcome the difficulties of welding MMCs The concept is based on the fact that experimental measurements indicate that the temperature of the droplets in the MIG welding process with spray transfer is between... module must be used to establish the arc opening An electronic igniter provides voltage peaks between the tungsten electrode and constrictor nozzle, generating a small spark in this region Thus, with the passage of the plasma gas a low intensity electric arc appears between the tungsten electrode and constrictor nozzle, called the pilot arc (non-transferred arc) The pilot arc forms a pathway of low electrical... enables welding of plates, 12.5 mm thick, in a single welding pass with a reduced heat input and thereby a reduction in the thermal affection of the base metal Trials to weld materials such as aluminum and MMCs with a thickness of 12.5 mm in one welding pass without joint preparation, i.e square edges, resulted in deficient welds with partial penetration Successful welding of these plates demands 3 or 4 welding. .. Although there are some exceptions, in electric arc welding epitaxial growth is a typical occurrence, wherein the first grains of the weld pool 24 Arc Welding nucleate directly from randomly oriented grains in the HAZ and grow toward the greatest thermal gradient within the puddle (Domey et al., 1995) On the other hand, the solidification in the IEA welding method is different due to the distinct generation... process by liquid diffusion; Schematic of the MIG welding process using (b) direct electric arc and (c) indirect electric arc (Garcia et al, 2002) a) b) c) Fig 3 Joint designs and typical geometry of the welds obtained; a) single V groove joint, b) IEA joint and c) MIEA joint Fusion Welding with Indirect Electric Arc 25 The Fig 3 shows different joint designs and dimensions as well as the typical geometries . Indirect Electric Arc 20 Rafael García, Víctor-Hugo López, Constantino Natividad, Ricardo-Rafael Ambriz and Melchor Salazar Part 2 Arc Welding Automation 45 Chapter 3 Arc Welding Automation. Part 1 Arc Welding Technology 1 Chapter 1 Hardfacing by Plasma Transferred Arc Process 3 Víctor Vergara Díaz, Jair Carlos Dutra and Ana Sofia Climaco D'Oliveira Chapter 2 Fusion Welding. ARC WELDING Edited by Wladislav Sudnik Arc Welding Edited by Wladislav Sudnik Published by InTech Janeza