3.1 Inclining test
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - 1989 MODU Code – Code for the Construction and Equipment of Mobile Offshore Drilling Units, 1989 – Resolution A.649(16) - Chapter 3 – Subdivision, Stability and Freeboard - 3.1 Inclining test

3.1 Inclining test

  3.1.1 An inclining test should be required for the first unit of a design, when the unit is as near to completion as possible, to determine accurately the light ship data (weight and position of centre of gravity).

  3.1.2 For successive units which are identical by design, the light ship data of the first unit of the series may be accepted by the Administration in lieu of an inclining test, provided the difference in light ship displacement or position of centre of gravity due to weight changes for minor differences in machinery, outfitting or equipment, confirmed by the results of a deadweight survey, are less than 1% of the values of the light ship displacement and principal horizontal dimensions as determined for the first of the series. Extra care should be given to the detailed weight calculation and comparison with the original unit of a series of column-stabilized, semisubmersible types as these, even though identical by design, are recognized as being unlikely to attain an acceptable similarity of weight or centre of gravity to warrant a waiver of the inclining test.

  3.1.3 The results of the inclining test, or deadweight survey and inclining experiment adjusted for weight differences, should be indicated in the operating manual.

  3.1.4 A record of all changes to machinery, structure, outfitting and equipment that affect the light ship data, should be maintained in the operating manual or in a light ship data alterations log and be taken into account in daily operations.

  3.1.5 For column-stabilized units, a deadweight survey should be conducted at intervals not exceeding 5 years. Where the deadweight survey indicates a change from the calculated light ship displacement in excess of 1% of the operating displacement, an inclining test should be conducted.

  3.1.6 The inclining test or deadweight survey should be carried out in the presence of an officer of the Administration, or a duly authorized person or representative of an approved organization.


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