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Some details about Shell Welder:
Shell Welder: Completed in 1955 by Clellands of Wallsend, of 569 gt. Sold in 1973 to Northwood Ltd. & converted to a dredger & renamed Steel Welder. In 1993 it was reported by Lloyds that she had been demolished.
I cannot find any sisters of that class or similar year build with Shell prefixes & yet there must be some. Shell Roadbuilder, Farmer, Steelmaker, Traveller, Glassmaker, etc.,built about the same time were all smaller (around 300 gt.) & were "flatties" - no superstructure - & have all long since been demolished.
Sorry that I can't be of more help.
I was Donkeyman in this one for a time, down below she carried a Chief and 2nd, I recall joining her at the Isle of Grain, no sooner was I unpacked than the Chief was knocking on my door with 200 ciggys and an offer of 4 hours a day buckshee overtime if I would do the 3rds watch. Money for nothing. Trevor