Schaffran Propellers after reconditioning
On a recent shaft job for a 121′ Heesen we had to remove the Schaffran props pictured here. If you are in the commercial vessel business their props would be small compared to tugs and freighters. However, in the 100 – 180′ mega-yacht business there are hefty units coming in at over 1,000 pounds each with a hub length over two feet. These props will push a 121 footer over 30 knots with twin MTU 4000 engines.
The Schraffran propellers are also hydraulically fit on the propeller shaft. There are no keys or keyways cut into the shaft. It takes specialized hydraulic equipment capable of up to 40,000 psi to expand the propeller hub and slide it off the taper.
Having hydraulic fit propellers eliminates one of the weakest points in a propeller shaft – the keyway. Great care must be taken with the removal and installation to make sure the shaft taper is not scored and the prop is “driven-up” on the shaft the correct distance.
High Seas has all of the specialized hydraulic tools and fittings to do the job right. If you are responsible for a vessel make sure you know if you have hydraulic propellers or couplers. This should be reviewed carefully with the contractor working on your running gear to make sure they are prepared to do it correctly.