Water lubricated metal and rubber bearings

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.

POM-C bearings without inner rubber

These bearings have been manufactured according to the ISO 9001 and other technical standards requirements to guarantee dimensional precision and material stability. They do not have any inner surface in rubber, as the inner and the outer surface are made of the same material. Such a bearing has several advantages: extreme dimensional stability and resistance, very low friction rate and excellent heat absorption which keep the shaft-bearing system very cool. Vibrations at low speed are better absorbed too.

To sum up the advantages of choosing these bearings are:

  • very low friction rate, which makes these bearings fit for a dry start;
  • complete material safety, as the POM C material can be used even in contact with drinkable water or food;
  • more precise tolerance, which is not affected by hygroscopicity and withdrawal;
  • advantages due to the inner spiral shape;
  • very easy replacement, as the POM C material is softer than metal (iron, steel, brass or bronze).

Spiral groove 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).