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The human species' use of technology began with the conversion of natural resources into simple tools. The prehistorical discovery of the ability to control fire increased the available sources of food and the invention of the wheel helped humans in travelling in and controlling their environment. Recent technological developments, including the printing press, the telephone, and the Internet, have lessened physical barriers to communication and allowed humans to interact freely on a global scale. However, not all technology has been used for peaceful purposes; the development of weapons of ever-increasing destructive power has progressed throughout history, from clubs to nuclear. | m __ MillAF I vllllVrl JJI DIVIE IB 3 E Lr ADP 1AIEI rMIU 2 li w w E L Lr 1111 L PREFACE The material contained within is current technical information on the application of the Submerged Arc Welding SAW process. It goes without saying that new up-to-date technical data is changing continuously. However basic information is always beneficial and it is hoped that this book will be helpful in that respect. All recommendations in this book are approximate values. We suggest that any welds or weldments be tested to assure that all codes and specifications are met. MILLER Electric Mfg. Co. TABLE OF CONTENTS PAGE General .1 Equipment Power Sources.1 Constant Current.1 Constant Potential.2 Alternating Current .2 Wire Feeding.2 Semiautomatic Submerged Arc.4 Flux Feeding.4 Arc Starting.5 Gun Positions.5 Electrical Extensions.5 Gunsand Flux Systems.6 Fixtures.6 Consumables Fluxes.8 Fused.8 Bonded.9 Agglomerated.9 Mechanically Mixed.9 Particle Size.9 Wire and Flux Identification .10 Wires.10 Preparing to Weld Joint Cleaning.15 Joint Fit-up.15 Bead Placement.15 Flux Depth.15 Preheat and Interpass Temperature.15 Making the Weld Starting.17 Sharp Wire Starts.17 Steel Wool Starts.17 Scratch Starts.17 Molten Pool Starts.17 Retract Wire Starts.17 High Frequency Starts.18 Voltage.18 Amperage Wire Feed Speed.18 Travel Speed. .19 Electrode Size.19 Electrode Extension.20 Polarity.20 Welding Hints Circumferential Welds.21 Fillet Welds. . .22 Lap Welds.22 Weld Defects and Troubleshooting .23 Special Applications.24 Cladding .24 Stainless Steel .24 Glossary.25 COPYRIGHT 1982 MILLER ELECTRIC MFG. co. Rev. 11 85 SUBMERGED ARC WELDING GENERAL Submerged Arc Welding SAW or Sub Arc as it s generally referred to is a unique welding process because there is no visible evidence that a weld is being made. The welding zone is completely shielded by a blanket of granular flux. Exposed arc eye protection is not normally used since the arc should be completely covered. The welding operator must however
