Section 2 General requirements

2.1.1 Limitations with regard to the application of these Rules are indicated in the various Chapters for differing ship types.

2.2.1 Plans are to be of sufficient detail for plan approval purposes. For all areas of structure listed below the submitted plans are to show all plating thickness, stiffeners sizes and spacings, bracket arrangements and connections. Where appropriate, the plans should clearly show the allowance for corrosion margin or enhanced scantlings. Welding, constructional arrangements and tolerances are also to be submitted and this may be in the form of a booklet.

2.2.2 In general all items of steel structure are to be shown except where they are ineffective in supporting hull girder and local loads and do not impinge on such structure.

2.2.3 Equipment seating and supports are to be shown where they require additional stiffening and support to be incorporated in items of hull structure. In such cases the loading on the seating is also to be supplied. Generally total combined equipment weights on seating less than 0,5 tonnes need not be considered.

2.2.4 Normally the plans for each item will be able to be contained on a few sheets. Unit or production drawings will not be accepted.

2.2.5 Plans covering the following items are to be submitted:

• Midship and other critical sections showing longitudinal and transverse material.
• Profile and decks.
• Shell expansion.
• Structural continuity plan showing shadow areas of openings, longitudinally effective material and primary structural continuity material.
• Oiltight and watertight bulkheads.
• Double bottom construction.
• Pillars and girders.
• Aft end construction.
• Engine room construction.
• Engine and thrust seatings.
• Fore end construction.
• Storing routes.
• Deckhouses and superstructures.
• Propeller brackets and appendages.
• Rudder, stock and tiller.
• Equipment.
• Loading Manuals and stability information booklets, preliminary and final (where applicable).
• Scheme of corrosion control (where applicable) including; location of anodes, method of attachment, details of cathodic protection system.
• Ice strengthening.
• Welding schedule.
• Hull penetration plans including scuppers, sea connections, overboard discharges, arrangements and fittings.
• Support structure for masts, derrick posts, cranes, RAS points, weapons handling/stowage or machinery lifting point and large items of equipment.
• Bilge keels showing material grades, welded connections and detail design.
• Flight deck arrangement and structure.

Additionally, for in-water survey the following plans and information are to be submitted:

• Details showing how rudder pintle and bush clearances are to be measured and how the security of the pintles in their sockets are to be verified with the ship afloat.
• Details showing how stern bush clearances are to be measured with the ship afloat.
• Details of high resistant paint, for information only.

2.2.6 The following supporting documents are to be submitted:

• General arrangement.
• Capacity plan.
• Lines plan or equivalent.
• Dry-docking plan.
• Towing and mooring arrangements.
• Corrosion margin policy.

2.2.7 The following supporting calculations are to be submitted:

• Equipment number.
• Hull girder still water and dynamic bending moments and shear forces as applicable.
• Midship section and other critical section modulus.
• Structural items in the aft end, midship and fore end regions of the ship.

2.2.8 In the process of plan approval and from Fatigue Design Assessment and Structural Design Assessment certain critical locations may be identified which require special attention. Plans and records of production are to be submitted in accordance with the construction monitoring procedures associated with the notation CM.

2.2.9 Where the specific notations are applied for additional plans will be required.

2.3.1 To facilitate the ordering of materials for repairs, plans listed in Vol 1, Pt 6, Ch 1, 2.2 Plans to be submitted 2.2.5 are to be carried on board the ship. They are to clearly indicate the disposition and grades (other than Grade A) of hull structural steel, the extent and location of higher tensile steel together with details of specification and mechanical properties, and any recommendations for welding, working and treatment of these steels.

2.3.2 Similar information is to be provided where aluminium alloy or other materials are used in the construction.

2.3.3 A copy of the final Loading Manual or Stability Information booklet, when approved, is to be placed on board the ship.

2.3.4 Details of any corrosion control system fitted are to be placed on board the ship.

2.3.5 Approved plans and information covering the items detailed in Vol 1, Pt 6, Ch 1, 2.2 Plans to be submitted 2.2.5 relating to in-water survey are to be placed on board the ship.

2.4.1 Where the proposed construction of any part of the hull or machinery is of novel design, or involves the use of unusual material, or where experience, in the opinion of LR, has not sufficiently justified the principle or mode of application involved, special tests or examinations before and during service may be required. In such cases a suitable notation may be entered in the Register Book.

2.5.1 Where scantlings in excess of the approved Rule requirement are fitted at defined locations as corrosion margins or for other purposes, the plans submitted for approval are to contain the enhanced scantling plan, together with the nominal thickness, less the enhancement adjacent, in brackets. See also Vol 1, Pt 6, Ch 6, 3.8 Corrosion margin.

2.6.1  Direct calculations may be specifically required by the Rules and may be required for ships having novel design features or in support of alternative arrangements and scantlings. LR may, when requested, undertake calculations on behalf of designers and make recommendations with regard to suitability of any required model tests.

2.7.1 Ships of unusual form, proportions or speed, with unusual features, or for special or restricted service, not covered specifically by the Rules, will receive individual consideration based on the general requirements of the Rules.