PLUS%2D2

3D Model

Class notation for extended fatigue life (design life 40 years).

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Purpose

To ensure that the structural scantlings and design of critical details in cargo areas are based on enhanced procedures for fatigue calculations. Intended for vessels with a long target life or vessels operating in especially harsh areas.

Benefits

  • Ensures that the vessel is designed based on extended requirements as to fatigue calculations and with the number of wave encounters related to a design life of 40 years for the PLUS-2 notation.

  • Includes additional requirements for the fatigue life of hull structural details.

  • Site surveys at the building yard and its suppliers and periodical surveys on board the vessel.

Features

This class notation denotes compliance with an expanded calculation procedure for the extended fatigue life of hull structural details. The PLUS-2 notation is intended for vessels operating in harsh areas and for vessels with increased target design life.

A ship operating in an especially harsh environment for most of its lifetime is subjected to more wear and tear than a similar ship operating on a worldwide basis. A robust design with respect to fatigue should therefore be aimed for at the newbuilding stage. Examples of such harsh areas are the North Sea, the North Atlantic and the North Pacific.

The fatigue requirement of the PLUS-2 notation is different from the main class in two aspects:

  • The number of design wave cycles has been increased

  • The extent of calculations has been increased with respect to structures to be assessed in relation to fatigue.

The class notation PLUS-2 is assigned followingn survey reports verifying compliance with the DNV rules.