Development of Fully Automated and Integrated ("Instamatic") Welding Systems for Marine Applications

ABSTRACT A two-year research program was conducted at M.I.T. to develop fully automated and integrated welding systems. These systems package many actions involved in welding so that certain prescribed welding jobs can be performed by a person with no welding skill. They have been nicknamed "instamatic"® welding systems, since they are similar to the easy-to-operate cameras. Following a general discussion on the development of the concept of the "instamatic"® we1ding system, discussions are given on two types of systems which have been built and tested: underwater stud welding systems, and those using arc welding processes. INTRODUCTION From a modest beginning in 1968, researchers at the Massachusetts Institute of Technology, under the direction of Professor Koichi Masubuchi, have conducted systematic research on underwater welding. Most of these efforts have been supported by the Office of Sea Grant, National Oceanic and Atmospheric (NOAA) of the Department of Commerce through the M.LT. Sea Grant Office. Research efforts have been carried out under the following projects:"Fundamental Research on Underwater Welding and Cutting", July 1971 through June 19741"Development of New, Improved Techniques of Underwater Welding", June 1974 through June 19762"Development of Joining and Cutting Techniques for Deep-Sea Applications, July 1976 thorough June 19803"Development of Fully Automated and Integrated ("Instamatic")® Welding Systems for Marine Applications", July 1980 through June 19824"Underwater Welding and Cutting by Remote Manipulation Techniques", a three-year program which started in July 1982. Results of the first three projects have been reported in M.I.T. Sea Grant Reports published in 1974,1977, and 1981. 1–3. Detailed results of the fourth project, which is discussed in this paper, will be prepared in another M.I.T. Sea Grant Report currently under preparation4. To date, twenty students have prepared theses for B.S., M.S., Ocean Engineer, and PH.D. degrees covering various related subjects. This paper has been prepared based on the last two theses, by D.W. Sch10erb5 and H. L. Gustin6. The objective of the research covered in this paper is to develop fully automated and integrated systems which package many operations involved in welding, including feeding the electrode, manipulating the torch, etc., through careful engineering, so that the welding systems can be operated by a person with no welding skill. These systems have been nicknamed "instamatic® welding systems", since they are similar to instamatic® cameras with which a person with little knowledge of photography can take good pictures. The systems developed can be used for a variety of welding jobs for marine, nuclear, space, and other applications. DEVELOPMENT OF "INSTAMATlC"® WELDING SYSTEMS Arc welding processes, including shielded metal arc (SMA), submerged arc, gas tungsten-arc (GTA), and gas metal-arc(GMA) processes, are widely used for fabricating metal structures, including ships, bridges, pressure vessels, pipelines, etc. Most of welding operations are done manually by skilled welders. Even automatic welding machines are operated by workers specially trained for the job. In most welding jobs performed on land, it is assumed that qualified welders and trained operators are available. This assumption is usually valid when welding fabrication occurs in shipyards and other plants.