A Case of Excessive Lateral Vibrations of Patrol Boat Shafting: Failures, Analysis and Solution

摘要

During the endurance trials of three identical patrol boats with "Vee" type main shafting system (3x900 kW each), three (of nine) shaft lines broke. The excessive lateral vibrations of the main shafting (excited by cardan joints) were recognized as the main cause of the failures, and some corrective measures were proposed. The authors of this paper were engaged a while later to make a thorough vibration measurement of the repaired boats. As the record showed that the improvement was not satisfactory, some additional more effective measures had to be accomplished.