Inspection and repair of Jahnel-Kestermann propulsion gearbox PGV 1060-450 

During one of their voyages the crew of the container vessel m/v Delta Hamburg noticed abnormal vibrations. They opened up the inspection covers of the propulsion gearbox and found damaged teeth of the input shaft. Because Stork gears & services was able to send a service engineer very quickly, Stork SGS was invited on board the m/v Delta Hamburg to conduct a more extensive gearbox inspection.  After removing the inspection cover it became clear that one teeth of the input gear was almost broken out of the shaft, the cracks ran through the complete root of the teeth on both sides. Also the teeth before and after the broken teeth were cracked for almost the whole length of the teeth. Furthermore one teeth of the pinion shaft had a piece broken out in the middle of the teeth. After the onsite inspection it became clear that the input pinion shaft needed to be renewed. The bullgear was also subject of further inspection and MPI (crack) tests. For regrinding and geometrical checks we preferred to have the complete gearbox in our workshop in Rotterdam. An additonal benefit of having the complete gearbox in our workshop is that we are able to perform a testrun before we send it back to the customer.		Location Sint Petersburg, Russia Workshop SGS Rotterdam, the Netherlands Total completion time Inspection date:       03-11-2010 Ready for transport: 10-12-2010 (scheduled) Market segment Shipping, container vessel Equipment Propulsion gearbox Jahnel-Kestermann, type PGV 1060-450 Input power max 9000 kW Total weight: approx. 23.000 kg The Gearbox Inspection report Transport to Rotterdam After the inspection it was decided it was best to ship the entire gearbox in one piece, including the casing, to the SGS workshop in Rotterdam. To dismount and transport the gearbox safely, weighing approximately 23.000 kg, it was necessary to torch a hole in the hull of the vessel.
During visual inspection it became clear that one teeth of the input gear was severly damaged. One teeth of the input gear was almost broken out of the shaft, the cracks ran through the complete root of the teeth on both sides.   The output shaft was in quite a good condition. All bearing faces were according to requirements. The gears on the output gearwheel showed some irregularities. Some small marks were found in the middle of the teeth and some minor fretting was observed on the top ends of the teeth.