Automatic Stud Welder for Surface and Underwater Applications

Abstract

As a company involved in underwater engineering serving the oil industry worldwide, our clients have frequently enquired about attaching studs to tubulars under water. Where this requirement has been to attach studs to structural members or to pipelines, where welds of equal, if not better, integrity to those achieved on the surface are specified, the only viable alternative has been dry habitat welding, with all the expense that is entailed in such an operation. Wet welding is unacceptable, as high hardness values are obtained in the HAZ, which may also contain hydrogen cracks. Wet welds in general also have poor appearance and an unevenness which can lead to slag entrapment in a multipass situation.