✨ Marine Safety Regulations
3254
THE NEW ZEALAND GAZETTE.
[No. 77
Rule XXXIII.—Breadth (B).
The breadth is the maximum breadth in feet amidships to the moulded line of the frame in iron or steel ships, and to the outside of the planking in wood or composite ships.
Rule XXXIV.—Moulded Depth.
The moulded depth is the vertical distance in feet, measured amidships, from the top of the keel to the top of the freeboard deck beam at side. In wood and composite ships the distance is measured from the lower edge of the keel rabbet. Where the form of the lower part of the midship section is of a hollow character, or where thick garboards are fitted, the depth is measured from the point where the line of the flat of the bottom continued inwards cuts the side of the keel.
Rule XXXV.—Depth for Freeboard (D).
The depth used with the Freeboard Table is the moulded depth plus the thickness of stringer plate, or plus T(L−S)/L if that be greater, where—
T is the mean thickness of the exposed deck clear of deck openings, and
S is the total length of superstructures as defined in Rule XL.
Where the topsides are of unusual form, D is the depth of a midship section having vertical topsides, standard round of beam and area of topside section equal to that in the actual midship section. Where there is a step or break in the topsides—(e.g., as in the Turret Deck ship) 70 per cent. of the area above the step or break is included in the area used to determine the equivalent section.
In a ship without an enclosed superstructure covering at least 0·6 L amidships, without a complete trunk or without a combination of intact partial superstructures and trunk extending all fore and aft, where D is less than L/15, the depth used with the Table is not to be taken as less than L/15.
Rule XXXVI.—Coefficient of Fineness (c).
The coefficient of fineness used with the Freeboard Table is given by—
c = 35Δ / L.B.d₁
where Δ is the ship’s moulded displacement in tons (excluding bossing) at a mean moulded draught d₁ which is 85 per cent. of the moulded depth.
The coefficient c is not to be taken as less than 0·68.
Rule XXXVII.—Strength.
The Assigning Authority is to be satisfied with the structural strength of ships to which freeboards are assigned.
Ships which comply with the highest standard of the rules of a Classification Society recognized by the Administration, shall be regarded as having sufficient strength for the minimum freeboards allowed under the Rules.
Ships which do not comply with the highest standard of the rules of a Classification Society recognized by the Administration shall be assigned such increased freeboards as shall be determined by the Assigning Authority, and for guidance the following strength moduli are formulated :—
Material.—The strength moduli are based on the assumption that the structure is built of mild steel, manufactured by the open hearth process (acid or basic), and having a tensile strength of 26 to 32 tons per square inch, and an elongation of at least 16 per cent. on a length of 8 inches.
Strength Deck.—The strength deck is the uppermost deck which is incorporated into and forms an integral part of the longitudinal girder within the half-length amidships.
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VUW Te Waharoa —
NZ Gazette 1934, No 77
NZLII —
NZ Gazette 1934, No 77
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Rules for determining Maximum Load Lines of Merchant Ships
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🚂 Transport & CommunicationsLoad Lines, Merchant Ships, Marine Safety, Regulations, Breadth, Moulded Depth, Freeboard, Coefficient of Fineness, Structural Strength