Caravel bearings are made of an outer shell in brass or bronze, stainless steel, aluminium, pvc, with an inner surface covered by vulcanized NBR rubber.
Shell and rubber are carefully pasted and the adherence deeply tested in our laboratory.
Shape, dimensions and number of the lubrication channels are designed according to precise mathematical and mechanical principles. The inner design of the rubber surface can be axial, spiral or helical, with one or more right- or left-hand principles, according to the shaft rotation, to help water in its action of lubrication and cooling of the shaft.
Easy assembling and replacement
Caravel water lubricated bearings meet every requirement in terms of inner and outer tolerance: when needed, they are grinded externally, to be assembled and replaced very fast.
Noise and vibrations damping
Water lubricated bearings are the ideal solution to limit and keep under control vibrations and noise: such a feature plays an important role on propeller shafts and industrial applications. It may happen that turning bodies are not perfectly balanced or extreme precision is required.
When the shaft’s rotation around its own axis does not coincide with its geometric center, the rubber’s extreme elasticity absorbs the vibrations in a very effective way. Laboratory tests have proved that vibrations do not spread to the outer shell. The NBR rubber is ideal to prevent damages and shaft.
The “Ploughing” method
The innovative “Ploughing” system has been developed to manufacture big bearings (for shaft diameters from 120 to 600 mm) avoiding the building of the inner mould to vulcanize the rubber and get the desired shape.
This method has proven advantages:
- Higher inner diameter precision, thanks to a round inner mould, easier to build. The round mould, with no protrusions corresponding to the channels, can be worked very easily, turned on the lathe and grinded.
- Outlined longitudinal grooves, designed in relation to mathematically worked out water flows which increase the reliability and duration of the bearing, especially when the shaft is quite heavy and must work horizontally.
- As a consequence of this production method, the usual delivery terms can go from 4 to 20 days.
Usually big bearings can be supplied in 30 days.
The “Ploughing” system is an effective technique which our company has developed to offer a concrete solution when our clients need big bearings in a very short time.
Spiral grooves bearings
Caravel bearings with spiral channels have been tested under the most severe conditions, on vertical test benches and applying considerable dynamic balancing loads in highly polluted and sandy water taken from the most critical environments. The shaft rotation activates a powerful pumping action supported by the grooves, with a considerably increased fluid velocity, a remarkable cooling, lubricating, and cleaning effect. Through these bearings the shaft is supported all along its length and its entire circumference and does not rotate in a polygonal bearing. Vibrations decrease to a negligible level; such an advantage is really important for bearings used on the propeller shafts of large luxury yachts. Thanks to their great reliability, these bearings are fit for applications on engines designed to work in very sandy areas, or where few opportunities for fast repair and maintenance are available. The radius of spiral channels may vary depending on the shaft diameter and the rotation direction (right or left).