Creative In-Situ solution restores generator to operation

Pielstick 2.3 generator shaft

A Florida power plant experienced a casualty on its Pielstick 2.3 Diesel / Gas Generator Set. The free end Dodge bearing on the generator had failed and required replacement. Inspection of the shaft (203.2 mm dia. X 610.00 mm length) revealed that there were significant surface cracks around the shaft and it would require repair.

Goltens proposed machining the shaft until it was free of cracks and fabricating a sleeve that could be shrink fit to the shaft to return it to its original diameter. The customer accepted the proposal and Goltens mobilized tools and in- situ machinists to site to undertake the repair. Cracks were significant and Goltens stopped machining at numerous diameters to evaluate the extent of the cracks. At 23.6 mm undersize, 4 cracks remained and a decision was made to local grind the cracks until removed prior to sleeving the shaft.

Once completed, the sleeve was heated to obtain the necessary clearance and shrink fitted to the shaft before it was finish machined and the generator reassembled and aligned.