Trans RINA, Vol 153, Part A4, Intl J Maritime Eng, Oct-Dec 2011


common. In some instances at the lower end of this size class designs have an L/B ratio as low as 5.5 with a corresponding increase in the B/T ratio to achieve the design deadweight. This is not simply a function of size however, with Handysize and Handymax vessels (20,000 to 55,000


tonnes deadweight) having very similar


dimensional ratios to the unconstrained Capesize vessels. The variation by class of ship is shown in Figure 8 and Figure 9.


Relaxing the beam constraint will allow vessels of the existing typical Panamax deadweight to be achieved with different and generally more conventional dimensional ratios, in addition to facilitating larger ships. The release of the beam constraint allows the L/B ratio for ships in this size range to reduce to a more contemporary value, namely providing the ability to carry more deadweight


0 1 2 3 4 5 6 7 8


0 50000 100000 Dwt Figure 8: Length to Beam ratio for modern bulk carriers6


3.5 4


2.5 3


1.5 2


0.5 1


0 0 50000 100000 Dwt Figure 9: Beam to Draught ratio for modern bulk carriers6 150000 200000 250000


Panamax Capesize Handy


150000 200000 250000


through increased beam rather than length, which is a more cost effective means of doing so even if not required for stability purposes. Of particular interest is the cluster of vessels in the new Mini-Cape deadweight range that have a beam of between 36.5m and


43.0m.


The reason for this upper constraint, 6m less than the new Panamax limit,


consistent with an appropriate design solution for vessels of this


deadweight possibly


is not clear but may simply be a and


also reflecting


production constraints in the producer shipyards. It is also apparent that the largest of these vessels also approach the new Panama Canal draught constraint of 15.2m but that some classes have a reduced operating draught to a level comparable to existing Panamax ships or even less. This dimensional data is shown in Figures 10, 11 and 12.


Panamax Capesize Handy


A-222


©2011: The Royal Institution of Naval Architects


B/T


L/B


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64