DNV DNVGL-CG-0156 PDF

General

Scope of the class guideline includes changes to main functions, ship purpose and class notations of the vessel. This includes changes to main dimensions or equipment affecting structural strength, machinery, stability, and safety. Additionally, it covers installation of temporary equipment for multiple or single voyage.

Vibrations

Extensive conversions/alterations may have adverse effects on the natural frequencies of parts of the vessel. The plan approval does not include consideration of vibrations in the hull structural elements in relation to the requirements for scantling given in the rules.

Stability

Stability is a very important aspect to clarify when planning a conversion/alteration. In particular, it should be noted that for a dry cargo ship over 80 m in length where no damage stability requirements have previously been in force, new damage stability requirements given by SOLAS may become applicable. It may thus be necessary to submit damage stability index calculations to the flag administration or class, if delegated, to demonstrate that the level of subdivision is not less than before the conversion/alteration.