Swedish Navy URF: 2014-15
URF is the original Swedish rescue submarine, large enough to take the entire crew of their small diesel electric boats off in one go. JFD won the contract to extensively upgrade the boat for an extended service life. This was completed and went onto trials before my time at JFD. As could be reasonably expected, there was a long trail of teething problems, many of which proved recalcitrant. I was given the task of fixing it through the winter at the Karlskrona naval base 2014/15. I had a great crew, I even managed to drag Charlie Sillett back from retirement.
The biggest problem that emerged however was not the fault of JFD. The completely new water trim system was made from 316 stainless steel. Bacteria in the low salt Baltic rapidly ate into the pipes and tanks and leaks began to appear. The Swedish Navy knew this happened to 316 in the Baltic but procurement were not in possession of this vital piece of information when specifying the material. The entire trim system had to be re-made using 6MO, a type of stainless steel that has proven to be resistant to Baltic water. To complement the welded assemblies, special fittings were made by Swagelok and Parker at eye-watering cost. Local highly skilled welders re-constructed the pipe system. If I blinked, I was back at Rolls Royce Nuclear.
The boat was successfully sea-trialled in the spring of 2015.