1、 RULES FOR BUILDING AND CLASSING BULK CARRIERS FOR SERVICE ON THE GREAT LAKES 2017 NOTICE NO. 1 JULY 2017 The following Rule Changes were approved by the ABS Rules Committee on 30 May 2017 and become EFFECTIVE AS OF 1 JULY 2017. (See http:/www.eagle.org for the consolidated version of the Rules for
2、Building and Classing Bulk Carriers for Service on the Great Lakes, 2017, with all Notices and Corrigenda incorporated.) Notes - The date in the parentheses means the date that the Rule becomes effective for new construction based on the contract date for construction, unless otherwise noted. (See 1
3、1-4/3.3 of the ABS Rules for Conditions of Classification (Part 1).) PART 3 HULL CONSTRUCTION AND EQUIPMENT CHAPTER 2 HULL STRUCTURES AND ARRANGEMENTS SECTION 3 DECKS (Add new Subsection 3-2-3/19, as follows:) 19 Hopper Slope (1 July 2017) 19.1 Hopper Slope as a Part of a Tank Where the hopper slop
4、e forms a part of a tank, the plating and strength requirements are as required for tank boundary bulkhead, see 3-2-7/3. 19.3 Hopper Slope not a Part of a Tank Where hopper slope is not a part of a tank, the inner bottom plating is to meet the minimum thickness requirement for inner bottom plating,
5、see 3-2-4/11. In lieu of meeting the inner bottom plating thickness requirement 3-2-4/11, the hopper slope plating and stiffeners are to meet 3-2-3/19.3.1 and 3-2-319.3.2. 19.3.1 Plating In lieu of meeting the inner bottom plating thickness requirement 3-2-4/11, the net thickness of the hopper slope
6、 plating is not to be less than t1, t2, and t3, as obtained from the following equations: t1= 0.73s(k1p/f1)1/2mm (in.) t2= 0.73s(k2p/f2)1/2mm (in.) t3= 6.35 mm (0.25 in.) where s = stiffener spacing, in mm (in.) k1= 0.342 ABSRULES FOR BUILDING AND CLASSING BULK CARRIERS FOR SERVICE ON THE GREAT LAKE
7、S .2017 1 Notice No. 1 July 2017 k2= 0.500 p = nominal pressure due to gravity at the lower edge of each plate, in N/cm2(kgf/cm2, lbf/in2) = k3ghccos2 + (1 sino)sin2 k3= adjustment factor to account for the Great Lakes environment = 0.870 g = specific weight of the bulk cargo considered, in N/cm2-m
8、kgf/cm2-m, lbf/in2-ft). g is not to be taken less than 1.471 N/cm2-m (0.15 kgf/cm2-m, 0.6503 lbf/in2-ft) = slope of wall measured from horizontal plane, in degrees o= angle of repose for the bulk cargo considered, normally 30 degrees (Re: “Code of Safe Practice for Solid Bulk Cargoes” published by
9、IMO) hc= vertical distance from the top cargo surface to the wall point considered in upright condition, in m (ft) f1= permissible bending stress, in the longitudinal direction, in N/cm2(kgf/cm2, lbf/in2) = 0.60SmY f2= permissible bending stress, in the vertical direction, in N/cm2(kgf/cm2, lbf/in2)
10、 = 0.85SmY Sm= strength reduction factor = 1 for Ordinary Strength Steel, as specified in 2-1-2/Table 2 of the ABS Rules for Materials and Welding (Part 2) = 0.95 for Grade H32, as specified in 2-1-3/Table 2 of the ABS Rules for Materials and Welding (Part 2) = 0.908 for Grade H36, as specified in 2
11、1-3/Table 2 of the ABS Rules for Materials and Welding (Part 2) = 0.875 for Grade H40, as specified in 2-1-3/Table 2 of the ABS Rules for Materials and Welding (Part 2) Y = minimum specified yield point of the plating, in N/cm2(kgf/cm2, lbf/in2) Nominal Design Corrosion Value (NDCV) is to be taken
12、as 2 mm (0.08 in.). 19.3.2 Stiffeners Each stiffener is to have sufficient section modulus SM to withstand the pressure p as defined in 3-2-3/19.3.1. 2 ABSRULES FOR BUILDING AND CLASSING BULK CARRIERS FOR SERVICE ON THE GREAT LAKES .2017 Notice No. 1 July 2017 PART 3 HULL CONSTRUCTION AND EQUIPMENT
13、CHAPTER 2 HULL STRUCTURES AND ARRANGEMENTS SECTION 6 WATERTIGHT BULKHEADS (Add new Subsection 3-2-6/11, as follows:) 11 Construction of Screen Bulkheads (1 July 2017) Screen bulkheads are non-watertight bulkheads often used to separate cargoes. Strength requirements for screen bulkhead plating, stif
14、feners, stringers, and webs are to be obtained from 3-2-6/7 with the corresponding h value reduced by half for thickness and section modulus calculations. However, in no case, is the screen bulkhead plating thickness to be taken less than 0.25 in. (6.35 mm). In lieu of applying the requirement indic
15、ated above, the “U” shaped part, which runs along the deck and side tanks for double hulls or the deck and side shell for single hulls, is to have section modulus SM not less than obtained from 3-2-5/11.1. See 3-2-6/Figure 2 for an example of screen bulkhead section modulus calculation. (Add new 3-2-6/Figure 2, as follows:) FIGURE 2 Screen Bulkhead Section Modulus Calculation Double Hulls (1 July 2017) ABSRULES FOR BUILDING AND CLASSING BULK CARRIERS FOR SERVICE ON THE GREAT LAKES .2017 3
