US2981217A - Ships of the horizontal handling type - Google Patents

Description

April 25, 1961 2,981,217 SHIPS OF THE HORIZONTAL HANDLING TYPE Jacques Delsuc, 11 Rue de Siam, Paris, France Filed Oct. 8, 1957, Ser. No. 688,943 Claims priority, application France Mar. 19, 1957 2 Claims. (Cl. 114-78) The device forming the object of the present invention relates to certain means of construction of ships of the so-called horizontal handling type, in which vehicles which run on the ground, such as lorries, trailers, halftrailers, lifting trucks or handling trucks can have direct access to the holds of the ship.

In these ships, in order to ensure the best cubic utilization of the ship, it is desirable to provide at least two decks corresponding to an equal number of superposed loading surfaces.

The reciprocal access from one deck to the other is obtained by means of ramps used by the vehicles during the operations of loading or unloading, one of these decks being capable of being directly connected to the quay by means of a movable ramp opening either through the stem or through the stem or through the side of the ship.

In ships of this kind with horizontal handling, the decks are generally made as wide as possible in order to reduce the number and the relative size of the ramps.

However, a drawback arises from the difliculty in complying with the compulsory conditions of safety. In fact, attempts to obtain the best cubic utilization of the ship, together with the best characteristics of the hull, lead to the use of the spaces situated below the water-line, which can be efiected by placing the lower deck below the water-line.

An arrangement of this kind is not however a priori compatible with safety regulations. These prescribe in fact that the buoyancy and the stability of the ship must 'be ensured even if, as a result of damage, a certain number of its quick-works become flooded with water.

In order to comply with this condition, ships of the usual type are divided by transverse water-tight bulkheads which divide the bottom into a certain number of water-tight compartments. These bulk-heads rise to a certain level above the water-line in order that there may be no communication between adjacent water-tight compartments, even if, as a result of the flooding of a compartment with water the water-line rises above its normal level.

At first sight, such arrangements are not compatible with the continuous deck constructions necessary for the use of ground transport vehicles. Thus, in the horizontalhandling ships which have been constructed up to the present time, the requisite safety is obtained by a further group of means, of which one consists in transforming the sides into compartmented water-tight caissons. How ever, an arrangement of this kind has a number of serious drawbacks; on the one hand it results in the loss of a substantial portion of the advantages which have been obtained by widening the ship; in fact, the decks proper are much less widened than the maximum cross-section of the ship. In the second place, the ship is thereby made substantially heavier. Finally, such a construction is necessarily very costly.

In the arrangement which forms the object of the pres- Paten d Apr-.2 6.

entinvention, solutionshave been preferred which comprise a lighter and less costly combination, and which make it possible to leave the decks the full extent of their width. 7

This arrangement consists in leaving intact the transverse bulk-heads forming water-tight compartments, such as those which are provided in ships of standard type, andin providing one ramp per water-tight compartment. However, since each ramp must have a sufliciently small slope to permit of easy negotiation by ground transport vehicles, and that the water-tight compartments are of necessity relatively short, and that it is necessary, at the outlet of the ramp on the lower deck in the water-tight compartment to have available a manoeuvring space sufiicient to enable transport vehicles to be brought into position, each ramp must be, at least partly, enclosed in the adjacent compartment.

This enclosure is eifected in accordance with the inven-. tion by considering the space located above the ramp as forming a casing entirely a partment to which it gives access. That is to say the normal transverse bulk-head, being cut in order to permit the passage of the ramp, is nevertheless re-oompleted by water-tight bulk-head elements which rise from the ramp to the levelof the upper ciently above the water-line.

There has been shown in the accompanying drawings an example of a ship provided with access ramps in accordance with the invention. 7

Fig. 1 is a diagrammatic view in partial cross-section of a'ship in accordance with the invention;

Fig. 2 is a perspective. View of a detail showing oneofi the access ramps;

Fig. 3 is a diagrammatic view in plan of an alternative form of construction;

Fig. 4 is a perspective transversal cross-section, showing the access ramps of the ship.

Fig. 1 shows a part of the hull of a ship comprising a continuous upper deck 1 and a lower deck 2 cut by the transverse water-tight bulk-head 3 into water- tight compartments 4 and 5, and a water-tight caisson 6 cut by the bulk-head 3 into two portions 7 and 8 which are water-tight in all directions. The ramps 9 and 10 which, in the example chosen, run in opposite directions, but which could quite Well have their slopes in the same direction, enable communication to be provided between the compartments 4 and 5 of the lower decks and the upper deck 1. Each ramp is entirely enclosed by a casing composed of water-tight bulk- head sections 11 and 12, which rise from the ramp itself up to the upper deck 1 to which they are connected. The space thus defined by these water-tight bulk-head members on the one hand and by the ramp on the other hand, thus forms part of the compartment to which the ramp gives access, but it cannot have any communication with the adjacent compartment in which however the ramp is enclosed, other than by the intermediary of the upper deck which is located above the highest levels of the water-line even of those which may occur after damage or defect which may cause flooding of a compartment with water.

A further form of construction of the invention consists in cutting the normal water-tight bulk-head of the ship along the longitudinal plane of symmetry of the ship, and in displacing the two half-bulk heads by a certain length and joining them both together along their internal edges by a longitudinal bulk-head member arranged along this axial plane (see Fig. 3).

In this form, the Water-tight bulk-head 3 is divided into three parts 3a, 3b and 3c and the ramps 9 and 10 are each comprised, over their entire height, in the intepart of the watertight comdeck, or at least to a level suffi- 4 and 5 respecof the longitudinal. wall Sain order to be spaced apart.

from the wall of the hull, and thatin case of damage, there is the minimum risk of two adjacent water-tight compartments being damaged and caused to communicate with eachother.

' An arrangement of this kind may be necessary in order to facilitate the operationof ground transport vehicles in the lower compartments by artificially increasing the lengths of these compartments without thereby increasing the water-tight spaces proper.

; I claim:

' 1. In a ship of the horizontal-handling type having at least an upper and lower loading deck and a plurality of transverse water-tight bulkheads vertically disposed between the decks and dividing the lower deck into separate, water-tight compartments; the improvement comprising a plurality of ramps sloping downwardly from the upper deck to the lower deck and attording access to the lower deck, the number of ramps being equalto the number of compartments served, said ramps being disposed in the compartments adjoining the ones with which they communicate and being inaccessible from the compartments within which they are disposed, a water-tight casing including each ramp separating the space enclosed by each casing from the compartment in which it is disposed with the space enclosed by each casing forming part of the compartment which is communicated with the ramp and adjoins the compartment in which the ramp is disposed, each casing being composed of two vertical bulkhead elements and the ramp disposed therebetween, the ramp being disposed in the longitudinal axial plane of the ship to traverse one of the transverse water-tight bulkheads, said vertical elements being bulkheads perpendicular to the transverse water-tight bulkhead and secured thereto, said vertical elements connecting each extremity of the ramp to a part of the hull of the ship.

2. In a ship of the horizontal-handling type having at least an upper and lower loading deck and a plurality of transverse water-tight bulkheads vertically disposed between the decks'and dividing the lower deck into separate,

water-tight compartments; the improvement comprising a plurality of ramps sloping downwardly from the upper deck to the lower deck and affording access to the lower deck, the number of ramps being equal to the number of compartments served, said ramps being located in the compartments adjoining the ones with which they communicate and being inaccessible from the compartments within which they are disposed,.a water-tight casing including each ramp separating the space enclosed by each easing from the compartment in which it is located with the-space enclosed by each, casing forming part of the compartment which is communicated with the ramp and adjoins the compartment in which the ramp is located, each casing being composed of two vertical bulkhead elements and the ramp disposed therebetween, the ramp.

being disposed in the longitudinal axial plane of the ship and the two vertical elements being perpendicular to the transverse water-tight bulkhead and connecting each extremity of the longitudinal ramp to a part' of the hull of the ship, said ramp and side vertical bulkhead elements forming a common portion between two adjacent compartments.

References Cited in the file of this patent UNITED STATES PATENTS Stewart Oct. 22, 1940

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