Enhancing Ship Generator Reliability by Modifying Bearings to Prevent Electrical Arcing Damage
Received: 12 May 2025 | Revised: 25 October 2025 | Accepted: 3 November 2025 | Online: 10 December 2025
Corresponding author: Rukmini
Abstract
Stray electrical currents in marine generators cause catastrophic bearing fluting, leading to frequent failures and operational downtime. The harsh maritime environment exacerbates this issue, demanding a more robust solution than conventional methods. This study introduces an innovative porcelain insulation sleeve applied to the bearing housing of a 250 kVA ship generator. Its effectiveness was evaluated through comparative in-situ testing, measuring vibration, temperature, and electrical parameters under a 22 kW load, with insulation thicknesses varying from 2.0 mm to 2.75 mm. The porcelain armor performed exceptionally. A 2.20 mm thickness was identified as optimal, achieving a 94% reduction in vibration and a 3.7 °C drop in operating temperature. Critically, the insulation's ultra-high insulation resistance (1000 GΩ) completely blocked the path of parasitic currents, eliminating the root cause of electrical arcing and fluting damage. This work demonstrates that applying porcelain insulation provides a definitive, maintenance-free solution to bearing fluting. The research validates a highly effective and practical engineering intervention that significantly enhances the reliability, safety, and service life of marine generators.
Keywords:
bearing current mitigation, marine generator reliability, porcelain insulation armor, fluting damage prevention, in-situ vibration analysisDownloads
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