WO1997005013A1

WO1997005013A1 - Seagoing vessel

Info

Publication number: WO1997005013A1
Application number: PCT/GB1996/001860
Authority: WO
Inventors: Michael Thurston Phipps; Hilary Claire Taylor
Original assignee: Michael Thurston Phipps; Hilary Claire Taylor
Priority date: 1995-08-01
Filing date: 1996-08-01
Publication date: 1997-02-13
Also published as: GB9515759D0; AU6626196A

Abstract

Water on the deck (11) of a seagoing vessel is hindered from transverse flow by a longitudinal barrier (12) on the deck. The water may be further contained by transverse barriers (15). The barriers can be adjustable in height, for example by having telescopic portions (16) or being inflatable, in order to facilitate movement of vehicles on the deck when loading and unloading.

Description

SEAGOING VESSEL

Seagoing vessels with open decks can be very unstable when even a small volume of water is present on the deck. As the vessel rolls to one side, water present on the deck will move to that side, thus tending to increase the amplitude of roll of the vessel and may even prevent it returning to a level attitude.

The present invention sets out to reduce this instability by providing one or more barriers secured to the deck in its longitudinal direction adapted at least to hinder the movement of water transversely of the deck. The barrier should be higher than any discontinuity in the deck caused, for example, by the overlapping of rivetted plates and should preferably be at least 10 cm and preferably 20 cm in height.

The barrier may be formed of plastics material and may be of trapezoidal section, having a broad base and a narrower top parallel thereto.

The areas defined by the longitudinal barrier may be defined at their ends by further barriers arranged transversely to the deck and these barriers may be inflatable. If they are not too high to be driven over, they can be solid and permanently affixed. They may possibly be of lower height than the longitudinal barriers.

Some or all of the barriers may be of adjustable height, for example by providing telescopic portions relatively movable vertically, preferably by hydraulic actuators. The barriers are conveniently raised after vehicles have been driven into position, if necessary by driving over the lowered barriers. The barriers may be bonded to the deck, which is particularly suitable when the barriers are of plastics material, or may be secured in ways conventional to shipbuilding, for example, by rivetting or welding.

Examples of the invention will now be described with reference to the accompanying drawings in which

Figure 1 is a cross-section through a deck of a seagoing vessel,

Figure 2 is a detail of the deck of Figure 1 in a horizontal position,

Figure 2a is the detail of Figure 2 showing the action of the apparatus of Figure 2 when the deck is rolled to one side,

Figure 3 is a plan of the deck of Figure 1 showing transverse barriers, and

Figures 4 and 5 show the details of Figures 2 and 3 with barriers raised.

On a conventional vehicle ferry deck 11, vehicles are parked in rows which are usually but not necessarily longitudinal of the deck. In Figure 1 the deck is provided with longitudinal barriers 12 between the rows extending substantially the whole length of the deck. The barriers 12 are 20 cm in height and, as can be seen in Figure 2, are wider afϋt-he base 13 than at the top 14 to provide them with strength when driven into from one side by a heavy vehicle.

At the ends of the rows (and possibly at intermediate points), transverse barriers 15 may be provided, either permanently or temporarily, either to be fixed in place during voyages, or for safety reasons inflatable automatically when the vehicle deck is closed against entry and exit of vehicles. If the vehicles have sufficient clearance, they may be driven over the barriers, and for this purpose the transverse barriers may be of a smaller height than the longitudinal barriers.

A comparison of Figures 2 and 2a will show that when the deck rolls, as seen in Figure 2a, water on the deck 11 collects in the troughs 21 formed by the barriers and so for the most part does not move a great distance transversely when the ship rolls. It is possible for some water to flow over the top of a barrier or round a free end, or even through the barrier if it is not completely watertight, but the barriers serve to restrain the water against rapid movement transversely of the ship and to retain much of the water in a given region transversely of the ship thus providing the ship with a righting weight to enable it to recover from its rolling motion.

A comparison of Figures 4 and 4a with Figures 2 and 2a shows the improved liguid retention when the barriers are provided with vertical extensions 16. The extensions are telescopic elements which can be stored within the main barrier body, but extended for operation hydraulically. The vehicles can be driven over the barriers of 20 cm height with the extensions stored, after which the extensions are raised to provide a greater liquid containment than if the extensions are not raised. The extensions may be of 15 cm extended height making the effective height of the barrier 35 cm. The troughs 21 of Figure 4a have a much greater capacity than those of Figure 2a.

Claims

1. A seagoing vessel comprising a deck and a barrier secured to the deck in its longitudinal direction adapted at least to hinder the movement of water transversely of the deck.

2. A vessel as claimed in claim 1 wherein the areas of the deck defined by a barrier are defined at their ends by further barriers arranged transversely to the deck.

3. A vessel as claimed in claim 2 wherein the further barriers are of lower height than the longitudinal barrier.

4. A vessel as claimed in any one of claims 1 to 3 wherein the height of a said barrier is at least 10 cm.

5. A vessel as claimed in claim 4 wherein the height of a said barrier is at least 20 cm.

6. A vessel as claimed in any one of claims 1 to 5 wherein a said barrier is formed of plastics material.

7. A vessel as claimed in any one of claims 1 to 6 wherein a said barrier is of trapezoidal section, having a

A broad base- and a narrower top parallel thereto.

8. A vessel as claimed in any one of claims 1 to 7 wherein some or all of the barriers are of adjustable height.

9. A vessel as claimed in claim 6 where a said barrier is inflatable.

10. A vessel as claimed in any one of claims 1 to 8 wherein a said barrier comprises telescopic portions relatively movable vertically.