Solution
Today, the company uses a combination of rolling and plain bearings for the reefing systems: A cylindrical roller bearing absorbs the axial forces. Two plastic bearings attached in front of and behind the rolling bearing provide radial support.
Reckmann partly builds the stainless steel cylindrical roller bearings themselves because there are no standard products that can withstand the required loads and environmental conditions. For plastic plain bearings, on the other hand, catalogue parts can be used. Here, the company uses
iglidur J bearings, which perform well under the high demands.
The material has also proven itself for years in many other fields of application as a fast- and slow-motion specialist with the best friction values. Another important criterion in this case is that the material be very dimensionally stable, even in wet applications. After extensive in-house testing, Reckmann confirmed the results and now uses the plain bearings in its hydraulic reefing systems. The bearings cope very well with the high mechanical requirements. The sailor can see for himself that the desired smooth-running properties can be achieved even with high sail pretension when he tries out the mechanical reefing system emergency operation with a standard winch handle. Even after a long break in which the sail is not reefed, the bearings turn extremely easily under full load.
Reckmann is so satisfied with the experience gained that it is using the material in another new development for boats up to 100 feet long. That development is the reefing system's cardan joint, the electric or hydraulic drive of which is installed below deck. The reefing system itself is mounted in the deck with a special swivel mount. Reckmann also uses
iglidur polymer plain bearings in the gimballed attachment's movement axes. Since a very high surface pressure is applied here as well, the installed plain bearings were tested extensively on the tensile test rig at up to 32 tons. But there is more: Some superyachts currently in the construction phase are even larger than the previous top models. So Reckmann is working on new reefing systems also featuring perfect optics, simple operation, and smooth-running properties despite high loads. And it intends to use wear-resistant bearings here, too.