Abstract
Lignum vitae had been used as seawater lubricated bearings for ships in the past. But nowadays, they are almost replaced by rubber bearings whose qualities are stable. This is because the rubber bearings have various excellent features such as self-alignment and vibration absorption, etc., and have shown good results. However, rubber bearings are elastically deformed by the shaft’s weight, and are inapplicable to large vessels. To solve this problem, PTFE bearings were developed. Friction coefficients of these bearings are greatly lower than those of rubber bearings due to the self-lubricity of the sliding material which lead to a greatly reduced fuel consumption. Moreover, application of these bearings in large vessels has shown good results; their abrasion resistance greatly exceeding that of rubber bearings.
