STEEL BARGES 1991 RULES FOR BUILDING AND CLASSING. NOTICE NO. 8 September The following Rule Changes are EFFECTIVE AS OF 1 JANUARY 2003.

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1 RULES FOR BUILDING AND CLASSING STEEL BARGES 1991 NOTICE NO. 8 September 2002 The following Rule Changes are EFFECTIVE AS OF 1 JANUARY SECTION 7 PART B MAIN FRAMING TANK BARGES 7B.3 Double Skin Tank Barges (Revise 7B.3.1 and 7B.3.2 as follows. Add new 7B.3.3 through 7B.3.6.) 7B.3.1 General (2003) The requirements of this part are generally intended to apply to barges of the type illustrated by Figures 7.11A, 7.11B, 7.11C, 7.11D, 7.11E, 7.11F, designed for the carriage of liquids in bulk. Unless specified otherwise in this Subsection, the required scantlings are to be developed from the appropriate paragraphs of this Section in association with Figures 7.1, 7.2, 7.3, 7.5, 7.6, 7.8, 7.9 and 7.10, due regard being given to whether framing members are located in a tank or void compartment. 7B.3.2 Double Bottom (2003) a Center Girder, Side Girder and Floors. In general the scantlings and arrangement of girders and floors are to be as required by 7A.3.3 unless otherwise specified in this paragraph. Where a centerline longitudinal bulkhead is provided, the scantlings and arrangement of side girders may be specially considered. Solid section stanchions fitted on tank top are not to be considered supports of double bottom structures unless the stanchions are part of a truss system. The floors and girders in the tank boundaries of double bottom are also to comply with Section 10 for deep tanks. The floors are to have stiffeners fitted at every longitudinal, unless the strength of the floors is proven by engineering analysis based on sound engineering principles. Where tanks adjacent to the double bottom are designed to be empty with the barge in a loaded condition, the floors and girders in the double bottom are to be specially considered. b Inner-bottom Plating. The thickness of the inner-bottom plating is not to be less than required by 7A.3.3i, nor is the thickness to be less than required by c Inner-bottom Longitudinals. Each inner-bottom longitudinal in association with the plating to which it is attached is to have a section modulus SM not less than obtained from the following equation: Where: SM = 7.8chs 2 cm 3 SM = chs 2 in 3 ABS RULES FOR BUILDING AND CLASSING STEEL BARGES

2 c = 1.0 = 0.5 where effective struts are fitted between inner-bottom and bottom longitudinals. h = the distance in meters (feet) from the inner-bottom to the following point: as defined in 7B.1.2 for a cargo or ballast tank, or the deck at side amidships for a void space s = the spacing of the inner-bottom longitudinals in meters (feet) = spacing of the floors in meters (feet) Where effective struts are fitted between inner-bottom and bottom longitudinals the section modulus of the inner-bottom longitudinals, in addition to complying with above, are also to be not less than 85 % of the requirement in paragraph 7A.3.3g for bottom longitudinals with c = d Bottom Longitudinals (2003) Scantlings of bottom longitudinals are to be obtained from 7B.3.2c where: c = 1.34 = where effective struts are fitted between inner-bottom and bottom longitudinals h = the distance in meters (feet) from the bottom to the following point: to a point located at two-third of the distance from the deck to the top of the overflow for a ballast tank, or the deck at side amidships for a void space (Subparagraphs 7B3.2e and f remain unchanged.) 7B.3.3 Trunk (2003) Trunk structure is to comply with the required cargo tank design head of Paragraph 7B.1.2 as well as Subection B.3.4 Deck Beams, Side Shell Frames and Longitudinal Bulkhead Stiffeners (2003) Deck beams in way of cargo tanks in association with the plating to which they are attached, are to have a section modulus SM as required by 7B.1.4. Similarly, deck beams and side shell frames in wing ballast tanks, in association with the plating to which they are attached, is to have section modulus SM as required by 7B.1.4 except that the design head h may be taken to two-third of the distance from the deck to the top of the overflow, or 0.91 meters (3 feet) whichever is greater. For void spaces, the design head h may be taken to the side amidships. For longitudinal bulkhead stiffeners, see B.3.5 Side and Deck Girders, Side Transverses and Vertical Web Frames on Longitudinal Bulkheads (2003) Each deck girder and vertical web frame on longitudinal bulkheads in way of cargo oil tanks, in association with any plating to which it is attached, is to have a section modulus SM as required by 7B.1.6. Similarly, each side and deck girder and side transverse in wing ballast tanks, in association with any plating to which it is attached, is to have a section modulus SM as required by 7B.1.6, except that the design head h may be taken to two-third of the distance from the deck to the top of the overflow, or 0.91 meters (3 feet) whichever is greater. Struts, transverse trusses or combination of struts and trusses may be used to strengthen the side structure (see Figure 7.11C). 2 ABS RULES FOR BUILDING AND CLASSING STEEL BARGES. 1991

3 7B.3.6 Non-tight Bulkhead (2003) Non-tight bulkheads, where fitted, are to be fitted in line with transverse webs, bulkheads or other structures with equivalent rigidity. They are to be suitably stiffened. The thickness of non-tight bulkheads is to be not less than the required plating of watertight bulkheads in and the stiffeners are to have a section modulus SM of half of those required for watertight bulkheads in (The existing Figure 7.11 is renumbered as Figure 7.11A.) FIGURE 7.11B Double Skin Barge without Trunk FIGURE 7.11C Open Framing with Transverse Trusses Utilized ABS RULES FOR BUILDING AND CLASSING STEEL BARGES

4 FIGURE 7.11D FIGURE 7.11E FIGURE 7.11F 4 ABS RULES FOR BUILDING AND CLASSING STEEL BARGES. 1991

5 SECTION 17 MACHINERY, PUMPS AND PIPING SYSTEMS 17.7 Pumps and Piping Systems (Add new sentence between existing second and third sentences in c to read as follows:) Fuel-Oil Systems c Valves on Fuel-Oil Tanks. Where pipe lines emanate from fuel oil tanks at such a level that they will be subjected to a static head of oil from the tank, they are to be fitted with positive closing valves located at the tank or where the pipe enters a machinery space. Where the fuel oil piping passes through adjacent tanks, the valve required above may be located where the pipe run exits the adjacent tank(s) provided the piping in the adjacent tanks is extra-heavy and has all welded connections. However, if the adjacent tank is a fuel oil tank, the pipe run within the fuel oil tank is to be at least Standard thickness. If the valves are installed on the outside of the tank, they are not to be of cast iron. (Remainder of text is unchanged.) ABS RULES FOR BUILDING AND CLASSING STEEL BARGES