Technical Q&A's
Maintenance of Propeller Shafts and Double Jointed Shafts
Propeller shafts are supplied maintenance-free or suitable for lubrication.
In the lubrication design (fig.1), the four bearings of a joint are lubricated via a tapered lubricating nipple in the centre of the joint. In special designs, the lubricating nipple may be placed on the base of the bearing bush.
The lubricating nipples must be cleaned before lubricating.
Fig 1.
The grease is forced into the distribution channel 2 via the tapered lubricating nipple 1 and transferred to the universal joint bushes, The grease penetrates between the roller bodies via the channels 3 of the pressure plate and edge 4 of the universal joint pin. When further grease is added, the grease penetrates through the valve-like opening gap of the seal lips 5 and the labyrinth. Excess grease emerges from gap 6 of the labyrinth.
Apply lubrication until grease is exuded from all four bushes.
!! If it is not possible to lubricate all four bearings fully, the shaft must be dismantled.
In standard designs, the length extension is maintenance-free.
For special lubrication designs, the sliding profile (fig. 2) is greased from a storage chamber (a) which is filled via pressure lubricating head (b). the storage chamber (a) should preferably be lubricated with the shaft retracted (vehicle loaded) so that an air cushion can form when the shaft is extended. To prevent damage to the cardan shaft or bearings of attached assemblies due to incorrect excess greasing (a) when the springs are compressed, if requested an excess pressure valve (c) can be installed which prevents an unacceptable pressure rise in the chamber.
Fig 2.
2.1 Lubrication Intervals
Unless specified particularly by the vehicle or system manufacturer, we recommend the following maintenance intervals. The data in the tables refers to European and comparable conditions.
!! Other operating conditions may require lubrication at shorter intervals. If propeller shafts are cleaned with pressurised water or vapour jets, lubrication must be applied after every cleaning.
Lubricating Interval for Joints