ОЦЕНКА УРОВНЕЙ ВИБРАЦИИ ДЕЙДВУДНЫХ УСТРОЙСТВ С МАСЛЯНОЙ СИСТЕМОЙ СМАЗКИ

Abstract

Periodic changes in the torque of the shaft line caused by the engine and uneven hydrodynamic resistance of the propeller are accompanied by vibration of the stern gear. The increased clearance because of loose fit of the stern bearing provokes vibrations of the shaft. With increasing clearance in the stern bearing, lubrication is interrupted, the constant of friction increases, which is accompanied by damage of sliding supports and failure of the bearing. Vibration can result in cracks in the ship's hull and foundation of the support bearings, damage of the stern bearing and the propeller shaft. With systematic measurement of vibration, the frequency analysis obtained allows to determine the nature of the fault and the causes of its occurrence, which greatly improves the reliability of the stern gear and prevents the developing defect. Measuring vibration of ship mechanisms and equipment is described in the Rules of the Russian Maritime Register of Shipping and used actively to monitor the technical condition of ships. The obtained results of vibration measurements are compared to the levels (categories) of the Rules. The ship shaft inspection system, approved by the classification societies, also recommends measuring vibrations of the stern bearings in operation for a modified (without shaft withdrawal) examination of the stern gear, which significantly reduces the costs. Unfortunately, the Rules and requirements do not contain standards for stern gear vibrations, taking into account their design features, which makes impossible to assess the condition of the mechanism. According to the measuring stern gear vibrations onboard the vessels projects 2608 and 1907 and to the comparison of results to the existed standards, there have been collected data for further evaluation of the levels and categories of the stern gear condition.