Section 7 Machinery survey – General requirements
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Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Naval Ships, January 2023 - Volume 1 Ship Structures - Part 1 Regulations - Chapter 3 Periodical Survey Regulations - Section 7 Machinery survey – General requirements

Section 7 Machinery survey – General requirements

7.1 Annual, Intermediate and Docking Survey

7.1.2 For ships assigned the notation ‘laid-up’, a general examination of the machinery is to be carried out in lieu of the normal Annual Survey requirements.

7.2 Complete Survey

7.2.1 While the ship is in dry dock, all openings to the sea in the machinery spaces, together with the valves, cocks and the fastenings with which these are connected to the hull, are to be examined.

7.2.2 All shafts (except screwshafts and tube shafts, for which special arrangements are detailed in Vol 1, Pt 1, Ch 3, 13 Screwshafts, tube shafts and propellers), thrust block and all bearings are to be examined. The lower halves of bearings need not be exposed if alignment and wear are found to be acceptable.

7.2.3 An examination is to be made of all reduction gears complete with all wheels, pinions, shafts, bearings and gear teeth, thrust bearings and incorporated brake and clutch arrangements where fitted.

7.2.4 The following auxiliaries and components are also to be examined:

  1. Auxiliary engines, auxiliary air compressors with their intercoolers, filters and/or oil separators and safety devices, and all pumps and components used for Mobility or Ship Type systems.

  2. Steering machinery.

  3. Windlass and associated driving equipment, where fitted.

  4. The holding down bolts, chocks of main and auxiliary engines, gearcases, thrust blocks and intermediate shaft bearings.

  5. Evaporators (other than those of vacuum type) and their safety valves, which should be seen in operation under steam.

7.2.5 All Ancillary systems are to be examined to ensure that there have been no modifications to the system that change the category, and no degradation that impacts on other systems or basic conditions on board.

7.2.6 All air receivers for Mobility or Ship Type systems, together with their mountings, valves and safety devices, are to be cleaned internally and examined internally and externally. If internal examination of the air receivers is not practicable, they are to be tested hydraulically to 1,3 times the working pressure.

7.2.7 The valves, cocks and strainers of the bilge and salvage system including bilge injection, are to be opened up as considered necessary by the Surveyor and together with pipes, are to be examined and tested under working conditions. The fuel oil, feed, lubricating oil and cooling water systems, also the ballast connections together with all pressure filters, heaters and coolers used for Mobility or Ship Type systems, are to be opened up and examined or tested, as considered necessary by the Surveyor. All safety devices for the foregoing items are to be examined.

7.2.8 Fuel tanks which do not form part of the ship’s structure are to be examined, and if considered necessary by the Surveyor, they are to be tested to the pressure specified for new tanks. The tanks need not be examined internally at the first survey if they are found satisfactory on external inspection. The mountings, fittings and remote controls of all fuel oil tanks are to be examined, so far as is practicable.

7.2.9 Where remote and/or automatic controls are fitted for Mobility or Ship Type System, they are to be tested to demonstrate that they are in good working order.

7.2.10 In addition to the above, detailed requirements for steam and gas turbines, engines, electrical installations and boilers are given in Vol 1, Pt 1, Ch 3, 8 Turbines – Detailed requirements,Vol 1, Pt 1, Ch 3, 9 Reciprocating internal combustion engines – Detailed requirements, Vol 1, Pt 1, Ch 3, 10 Electrical equipment and Vol 1, Pt 1, Ch 3, 11 Boilers respectively. In certain instances, upon application by the Owner or where indicated by the maker’s servicing recommendations, LR will give consideration to the circumstances where deviation from these detailed requirements is warranted, taking account of design, appropriate indicating equipment (e.g. vibration indicators) and operational records.

7.2.11 Where machinery installation includes ‘lifed items’ the requirements of Vol 1, Pt 1, Ch 2, 4.5 Existing ships – Periodical Surveys 4.5.21 are applicable.


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