DNV DNV-RU-SHIPS PART 4 CHAPTER 4 PDF

Calculation methods

The Society has several alternative advanced shaft design requirements in addition to the acceptance criteria based on IACS UR M68.

This section of the rules contains the following calculation setups:

— DNV method, simplified diameter formulae for plants with low torsional vibration such as geared plants or direct driven plants with elastic coupling [2.2.4]

— DNV detailed method, DNV-CG-0038 Calculation of shafts in marine applications [2.2.5]

— DNV method for stainless steel shafts, simplified diameter formulae with low torsional vibration subjected to sea water [2.2.6]

— IACS UR M68, simplified calculation method for shafts in direct coupled plants [2.2.7].

Application

Shafting elements

Shafting is defined as the following elements:

— shafts

— rigid couplings as flange couplings, shrink-fit couplings, keyed connections, clamp couplings, splines, etc. (compliant elements as tooth couplings, universal shafts, rubber couplings, etc. are dealt with in their respective sections)

— shaft bearings

— shaft seals.

Shafts or couplings made of composite materials are subject to special consideration. This section also deals with the fitting of the propeller (and impeller for water jet).

The rules in this section apply to shafting subject to certification for the purposes in Ch.2 Sec.1. Not applicable for generator shafts, except for single bearing type generators. Only applicable to shafts made of forged or hot rolled steel. Shafts made of other materials will be considered on the basis of equivalence with these rules.

General requirements

Ch.2 describes all general requirements for rotating machinery, and forms the basis for all sections in Ch.3, Ch.4 and Ch.5.

Standard design

Standard design is components which a manufacturer has in their standard product description and manufactured continuously or in batches in order to deliver for general marked supply.