Umeå Energi was looking for a qualified supplier to perform a regular operating hour-based major overhaul on the Siemens SST 600 turbine at the Dåva combined heat and power plant (CHP) just outside the city of Umeå. Fortum’s assignment consisted of the unit to be dismantled and inspected, its parts cleaned and repaired where necessary, and, finally, reassembled.
Without any hiccups, a turbine major overhaul normally takes around one month. But it is very common that opening the machine uncovers something surprising – as was the case with this turbine. As the dismantling work progressed, findings requiring extensive repairs were discovered in the rotor, stator, and control valves.
Fortum reacted fast to the findings and provided descriptions of the damage along with recommendations on how to repair the damage in the most cost- and time-efficient way. The overhaul was first extended by six weeks, but in the end the solution prolonged the overhaul by only four weeks.
”During the work, we were able to quickly handle the findings that required action. Fortum’s team on site handled their job extremely professionally,” says John Josefson, Operations Technician at Umeå Energi.