ABS Requirements: Sterntubeless Vessels

The American Bureau of Shipping, in June, issued Requirements for Sterntubeless Vessels with Water Lubricated Bearings.

This document has been developed to address the requirements for the design arrangement of the aft part of a vessel, where the aftmost bearing of the vessel’s shaftline is water lubricated, there is no sterntube cylinder, or a sterntube oil cooling tank and a dry stern inspection chamber is formed in the same area, hereby called a “stern inspection chamber”.

The document provides criteria for additional calculation requirements, such as design optimization for shaft alignment, as well as more detailed requirements regarding design characteristics, such as the design of a stern inspection chamber and an appropriate cooling sea-water supply and conditioning system.

Subject to verification of satisfactory operational records and surveys required for maintaining the TCM-W notation, as per 7-9-20/7 of the ABS Rules for Survey After Construction (Part 7), the vessels assigned with STBLess-W Notation, the tailshaft survey interval required by 7-2-1/13.1.3 may be extended under the arrangements described in this document.

If you need more information, please visit the ABS Rules and Guides page, where the document is available FOR FREE.