B6

An initial investigation into the use of homopolar pulsed welding of pipe is presented. A description of the welding process is presented and compared with other welding processes currently employed and anticipated in the offshore industry. The advantages of homopolar pulsed welding in J leg pipe laying applications is presented. Welds can be made at a single weld station in seconds with this process.

The physical properties of test welds made from 3.5 inch diameter X42 pipe are presented. The physical tests of the welds indicated that the welding process has the potential for practical field application in a lay barge. However, significant further work is required to develop controls for the process to improve the repeatability of the welds, determine the sensitivity of the process to geometric misalignment of the pipes, and determine the best approach to improving the weld line notch toughness.