Vesconite Stern Tube Bearing Chosen During Tanker Repair

In the late 1990s, a large tanker sustained hull and machinery damage after running aground near the entrance to a South American port channel. Following the recovery of the vessel and the removal of remaining cargo, it was taken to a nearby yard for extensive repairs.

As is common in salvage and repair operations of this nature, the ship’s stern tube and rudder assemblies were subject to detailed inspection in line with classification society requirements. 

Post-grounding evaluations often reveal the potential for misalignment and bearing wear, particularly if a vessel has been exposed to seabed contact. Class surveyors typically call for withdrawal of the propeller shaft, removal of the rudder, and inspection of the associated bearings, with replacement required if wear or damage exceeds tolerance.

In this case, one of the vessel’s stern tube bearings was replaced during the repair period. A Vesconite bearing was selected, sized at 513 x 448 x 600 mm, and fitted in 2001. The choice of material was influenced by Vesconite’s favourable properties in water-lubricated stern tube applications, including its dimensional stability and low wear rate in abrasive operating conditions.

The fitting of a new bearing was consistent with best practice for post-salvage maintenance, where both stern tube and rudder bearings are routinely inspected and replaced if there is evidence of misalignment or wear. This ensures the continued reliability of the propulsion and steering systems, which are critical to vessel safety and class reinstatement.

This case highlights both the importance of thorough bearing inspection following salvage operations and the value of advanced bearing materials in ensuring long-term performance in demanding marine environments.

The vessel, built in 1988 as a crude oil tanker, has since been converted to an offshore storage and production unit and is currently registered in Indonesia. She is classed with DNV and measures 247 m in length with a beam of 42 m.

This article was originally posted to Vesconite Bush Talk.