The National Transportation Safety Board (NTSB) has certainly An improperly sized bearing led to an engine failure and subsequent fire aboard an offshore supply vessel near Seattle last year.
The incident occurred on May 27, 2022 when the supply ship sea guard was given a test drive in Shilshole Bay. The ship number. A mechanical defect occurred in diesel generator engine 3, which led to a fire in the engine room.
Fortunately, no injuries or pollution were reported, but damage totaled $1.1 million.
Prior to the incident, maintenance was performed on all four main diesel generator engines between January and February 2022. Following the maintenance, full functional tests of the ship’s systems were carried out on open waters. However, during the test drive, the engineering crew heard a loud noise and noticed flames near the number. 3 main engine. They immediately deployed the ship’s carbon dioxide fire suppression system to extinguish the blaze.
Investigation revealed that the main journals of the #3 main engine were machined to a smaller diameter and undersized bearings were fitted sometime prior to the 2022 service. When the service was performed, Caterpillar service technicians could not identify the bearing part number on the service report and replaced it with a standard size bearing.
The incorrect size of the bearing caused lubricating oil to leak out of the larger clearances, resulting in a drop in lubricating oil supply pressure. This led to a rapid increase in temperature in the connecting rod bearings, which led to the failure of several engine components during engine operation.
The NTSB determined that the primary cause of the engine failure and subsequent fire on the sea guard was the replacement of a crankshaft main bearing with an incorrectly dimensioned bearing as part of an engine overhaul. This failure occurred because the engine service technicians could not identify the part number of the removed bearing, resulting in a loss of lubricating oil pressure in the adjacent connecting rod bearings.
The report emphasized the importance of correctly replacing engine components during maintenance to ensure safe and reliable ship operations. It was stressed that ships’ crews and equipment manufacturers’ technicians must carefully identify and document the part numbers of all components removed from shipboard equipment. The use of tracking systems was also recommended as an effective record-keeping method to ensure correct selection of replacement parts during reinstallation.
Due to the engine failure and fire incident, the local Caterpillar service company implemented a new service tracking system that allows technicians to upload pictures and reports via their cell phones to improve documentation and information sharing between technicians.
Read the report: Marine survey report 23-08