The work was carried out five metres underwater on 8mm thick plate in the vertical down and overhead positions. It simulated the sort of welding required in repair of offshore structures, ship repair or harbour sheet pile work. ‘The welding and evaluation of electrode operability were carried out by experienced welder-divers’ added Abson. ‘Among their tasks they had to complete a questionnaire on various aspects of the electrodes’ behaviour.'
‘Even while they were at the bottom of the tank, they were interviewed, on the intercom, about how the electrode handled, the metal transfer characteristics, how the slag flowed, and whether it was easily removable. Some welds for instance needed considerable interrun grinding. That’s important to know because it increases your dive time’.
The electrode operability influences the weld finish, which was very variable. The survey included an evaluation of the integrity of the finished welds and mechanical testing.
Subsequent surveys, following the same evaluation procedure, have been carried out on additional ferritic electrodes and some nickel-base electrodes.
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