The National Transportation Safety Board (NTSB) has reported that an engine failure and fire aboard the Ocean Guardian offshore supply ship last year was caused by an improperly sized bearing on the No. 3 diesel generator engine. During a sea trial in May 2022, the engineering crew heard a loud bang and observed flames near the engine. The crew was able to extinguish the fire using the ship’s carbon dioxide fire suppression system, but the No. 3 engine and surrounding equipment sustained damage, causing $1.1 million in damages.
NTSB investigators found that the main journals of the three main engines were machined to a smaller diameter and undersized bearings were installed at some point prior to the 2022 service. During the 2022 service, Caterpillar service technicians did not identify the bearing part number on the service report and replaced it with a standard-sized bearing. Due to the incorrect size of the bearing, lubricating oil could leak from the larger clearances of the bearing, reducing lubricating oil supply pressure and causing the connecting rod bearings to rapidly increase in temperature and detach several engine components while the engine was running.
The report emphasized the importance of proper replacement of engine components during maintenance, to ensure safe and reliable ship operations. The report recommended that vessel crews and equipment manufacturer technicians should carefully identify and document the part numbers of all components removed from shipboard equipment, and that tracking systems should be used to ensure correct selection of replacement parts for reinstallation.
After the engine failure and fire, the local Caterpillar service company switched to a new service tracking system that allows technicians to upload images and reports to their cell phones to improve documentation and information sharing between technicians. The report provides valuable insights for the marine industry and highlights the importance of proper maintenance for safe and reliable ship operations.
The incident underscores the importance of proper maintenance and the need to ensure that all equipment is properly inspected and serviced, particularly when working with critical components such as engines. Implementing proper tracking and documentation systems can help prevent costly and dangerous incidents like the Ocean Guardian engine failure and fire.