EP1524187B1 - Liferaft manoeuvrable from a davit - Google Patents

Description

The present invention relates to improvements made to liferafts maneuverable under davit and comprising for this purpose fastening means adapted to be caught in a davit hook, these rafts being equipped with an armament comprising at least one heavy load or heavier than the others.

The invention aims more specifically, although not exclusively, at survival rafts, in particular of the pneumatic type and of large capacity (for example from 12 to 50 persons, or even more) which equip, in particular, passenger transport vessels ( cruises, car ferries, ...).

The raft is generally provided with a survival armament (survival equipment, food, drink, ...) which, in the case of a complete armament (called "pack A"), includes in particular 1.5 liters of fuel. water and 1 kg of food per person. The inflation device of the raft is also heavy. For a raft of large capacity (several dozen people), this weapon is heavy.

The equipment of the raft is divided into several loads enclosed in waterproof bags arranged on the bottom of the raft along the pneumatic float.

These various loads, on the one hand, do not generally all have the same weight, some being notably heavier than others, and, on the other hand, can not be distributed symmetrically around the bottom of the raft, particularly in Due to the fact that, in the storage state of the raft in its container, some parts of the equipment are grouped in bags to facilitate the folding of the raft.

Furthermore, a maneuverable davit raft generally comprises lines which are distributed peripherally on the inflatable float and whose respective free ends are secured to a fastening member such as a shackle adapted to be gripped by the davit hook. The folding of the raft for its confinement in the container is carried out in the deflated state. In most bends specific to rafts under davits, the end portions of the lines, with the shackle to which they are joined, leave the tent covering the raft (or canopy) through an opening provided at the top thereof. In addition, the shackle is, when folding, brought to the front of the folded raft, above the bags containing the equipment so that, once the assembly is enclosed in the container, the shackle is easily accessible after opening. a hatch provided in the container wall.

For the implementation of the raft, the shackle is, after opening the container door, hooked to the davit hook, the davit lifts the container, overflows and brings it in position at the bridge. The swelling of the raft is then initiated using a percussion halyard provided for this purpose: the container opens and releases the entire raft which, not yet inflated pressure, is first in the form of a "cone" hanging from the shackle, then gradually takes shape during inflation. Finally the inflated raft is suspended at a single point (the shackle) located approximately vertically above the center of the raft.

However, the asymmetry mentioned above in the distribution of the equipment charges makes that, because of its attachment at a single central point, the raft is strongly unbalanced and consequently is inclined significantly.

For better clarity, it is illustrated in Figure 1 of the accompanying drawing, an example of a davit maneuverable pneumatic type liferaft, arranged in position for the boarding of passengers. The life raft 1 comprises, schematically, a float 2 with two superposed pneumatic tubes and a bottom 3. The lines 4 integral with the float 2 are joined superiorly to attachment means that can advantageously be constituted by a shackle 5 in which is engaged the hook 6 of a maneuvering davit 7. The davit 7 is for example arranged on a deck 8 of a ship 9 and is used to maneuver the raft, as indicated above, for the purpose of boarding the passengers (the boom E is the entrance opening - not visible - of the raft).

In the raft 1 are different charges in the form of sealed bags 10 ₁ , 10 ₂ , ... containing armament equipment, at least one of these charges 10 ₂ being substantially heavier than the other loads 10 ₁ , .. . These charges rest on the bottom 3 along the float 2, without being symmetrically distributed. In addition, the raft inflation equipment (gas bottles 11), which is fixed externally under the bottom 3, is also heavy. The accessibility requirements for at least some of the equipment bags, materials, etc. mentioned above lead to the fact that, in particular, the bag containing the heaviest load 10 ₂ and the gas cylinders 11 are located substantially on the same side of the raft, on the side of the entrance E.

As a result, the raft 1, suspended from the davit 7, leans appreciably on the heaviest load side 10 ₂ and its inclination α with respect to the horizontal is sensitive or significant as visible in Figure 1 (this inclination can typically be 30 to 40 °). This inclination results in an excess height h of the center of the raft with respect to its most offset edge downward.

This inclination is too large and the weight of the raft provided with all its loads 10 ₁ , 10 ₂ , ... is too high to attempt to straighten, at least in part, the raft manually by pulling it by means of a halyard.

This imbalance of the raft suspended under the davit poses several problems.

The boarding of the passengers is carried out while the raft, suspended under the davit and overflowed, is at the height of the bridge. If the raft is tilted as shown in Figure 1, it is necessary to lift the raft tilted higher than necessary to bring the entry E (located on the side of the lowest raft) at deck height. This requires a useful maneuvering height under the davit that is substantially greater than the minimum height required for a raft that would not be inclined (height of the raft deployed, the hook and the primer of the operating cable). It follows that the davit must be constructed accordingly, with increased height: this greater height is penalizing, or even incompatible with the facilities of the ships' decks, and in addition the davit thus arranged is more expensive.

In addition, the davits are generally pivoting, as shown in Figure 1. To bring the edge of the inclined empty raft in contact with the edge of the ship for the boarding of passengers, it is necessary first of all to make turn the davit in the direction of the interior and then, once the raft balanced by the boarding of the first passengers installed opposite the highest loads, to turn the davit outward to keep the raft become approximately horizontal in contact with the edge of the bridge. These maneuvers are penalizing as well because they complicate boarding (in addition the boarding area moves along the edge of the bridge depending on the contact of the raft with this edge, itself dependent on the angular position of pivoting of the davit) that mainly because they slow the boarding.

It should also be noted that these difficulties in maneuvering the raft with the davit are considerably amplified if the ship is in damaged conditions (according to the SOLAS Regulations, the use of davit rafts must be ensured when the ship is side sill of 10 ° on one side or the other and / or a plate of 20 ° on the front or the back).

On the other hand, if the initial inclination of the raft is not compensated for by raising the raft using the davit, the edge of the raft where the entry E is located is located significantly below the deck of the ship. It is then necessary that the first people jump from the ship in the raft, which is a difficult exercise, even perilous especially in the presence of rough seas and / or a strong wind. Here again, the boarding operation is slowed down.

Finally, the succession of maneuvers to lift the empty raft inclined to bring it up to the edge of the deck of the ship, then to lower it once it is balanced by the first people on board requires on the part of the crew the knowledge of the maneuvers required and a particular training.

Finally, it should be emphasized that the trend today is to arm ships with rafts of increasing capacity to compensate for the numerical reductions of crew members (each raft launched must bring at least one crew member who orders it). This increased capacity of rafts results in large dimensions and increased equipment loads (especially in survival rations) placed on the periphery of the raft: as a result, the tilting torque of such rafts suspended at a single central point becomes more important and that its empty inclination becomes very consequent, which makes the difficulties exposed above particularly crucial.

The object of the invention is to propose an original solution which makes it possible to eliminate at least a large part of the disadvantages which have just been exposed presented by the current arrangements of life rafts and which lead to allowing the raft raised by a davit to occupy a position much closer to the horizontal.

For these purposes, a life raft as explained in the preamble is characterized, being arranged according to the invention, in that the heavy load or at least the heaviest load of the armament is secured to the aforesaid means of hanging of the raft.

Thanks to this arrangement, the heavy load or at least the heaviest load is physically separated from the raft with which it is no longer in contact once it is inflated and suspended from the davit, so that the raft is significantly less imbalance and can occupy a position closer to the horizontal. Being suspended from the attachment means of the raft, this heavy load or the heaviest remains however above the raft during maneuvers and falls into it after the launching and detachment of the davit hook.

The solution proposed in accordance with the invention therefore makes it possible to maintain the raft in a correct situation leading to a rapid boarding process and not requiring any equipment, particularly davits, particular. In addition, it does not require any additional intervention of crew members, nor any additional training of them.

In the case where the armament is divided into several heavy loads among which some are substantially heavier than the others, these heavier loads are secured to the attachment means of the raft.

In practice, the attachment means of the raft generally comprise several lines joined to a shackle adapted to be gripped by a davit hook and the heaviest load or loads are secured to the shackle.

The arrangements according to the invention find a particularly interesting application in life rafts of large or very large capacity which are more sensitive to an imbalance of their load when suspended from the maneuvering davit, and thus the invention finds a particularly interesting application in pneumatic life rafts.

The invention will be better understood on reading the following detailed description of an embodiment. preferred given purely by way of purely illustrative example and shown in Figure 2 of the accompanying drawing.

FIG. 2 repeats the representation given in FIG. 1, except that the heavier load 10 ₂ is no longer fixed inside the raft, but is secured to the attachment means represented by the shackle 5 so as to that, the raft being suspended, the heaviest load _{2 2} be suspended from the shackle 5 above the raft without touching it. The load 10 ₂ can be secured to the shackle 5 either directly or as illustrated in Figure 2 by means of a strap 12 attached to the shackle 5. Under these conditions, the load 10 ₂ no longer influences the position raft 1.

For example, in the typical example of a raft with a capacity of 37 people, its total empty weight is of the order of 240 kg (without the container); the survival ration (1.5 ℓ of water and 0.5 kg of food per person) weighs a total of 74 kg, or about 30% of the mass of the raft. The bag or bags containing these rations, suspended from the shackle, no longer participate in the imbalance of the empty raft.

As illustrated in FIG. 2, the better balanced raft occupies a position closer to the horizontal, the residual inclination resulting from the non-symmetrical distribution of the other loads or masses, in particular of the inflation cylinder or bottles 11. It becomes thus possible to greatly reduce the residual slope of the raft, which can be for example typically of the order of 16 ° maximum. The implementation of the raft is then greatly improved since the maneuvers of the davit are limited to those strictly necessary; the first person embarks in non-hazardous conditions even if the raft is slightly inclined and alone it rebalances the raft. In addition, if necessary, the raft heavily lightened can be pulled and held against the edge of the bridge by means of a halyard to facilitate boarding, including rough sea. It avoids the complications of maneuvers required by a strongly inclined raft and accelerates boarding, while maintaining davits of minimum height.

In the case where the armament of the raft is distributed in the form of loads, several of which are substantially heavier than the others, these heaviest loads are all attached to the shackle 5 (as illustrated with the load 10 ₃ attached to the shackle 5). ).

As an alternative, the load ₃ has been illustrated as being suspended from the shackle 5 by means of a strap 13 which passes into the free-sliding shackle and which is attached to the raft, for example at a point on a float so that, by appropriate choice of the length of the strap, the load ₃ is raised automatically above the raft during inflation thereof.

The provisions according to the invention make it possible to eliminate the disadvantages set forth in the preamble, without however resulting in a significant complication or a significant additional cost of the raft thus equipped. In addition, an arrangement according to the invention makes it possible to maintain a folding procedure of the raft, for its housing in the container, substantially similar to that practiced hitherto, with the maintenance of the loads of equipment in the vicinity of the hatch provided in the container wall for access to the hitching shackle hook davit.

Claims (6)

1. Life raft (1) adapted to be launched by davit (7) and comprising for this purpose hanging means (4, 5) able to be held in a hook (6) of the davit (7), this raft (1) being fitted out with equipment comprising at least one load (10₂) that is heavy or heavier than the others, characterized in that the heavy or heavier load (10₂) is attached to said raft hanging means (4, 5),
   whereby, when the raft is hoisted by the davit, the heavy load or at least the heaviest load remains suspended from the raft hanging means without touching the raft, and the raft, being much better balanced, occupies a more horizontal position.
2. Raft according to Claim 1, characterized in that the equipment is distributed in several heavy loads (10₁, 10₂, ...), some (10₂) of which are substantially heavier than the others, and in that said heaviest loads (10₂) are attached to the raft hanging means (4, 5).
3. Raft according to Claim 1 or 2, characterized in that the raft hanging means (1) include several slings (4) brought together at a shackle (5) and in that the heaviest load or loads (10₂) are attached to the shackle (5).
4. Raft according to any one of Claims 1 to 3, characterized in that the heaviest load or loads (10₂) are each suspended from the raft hanging means by means of a strap (12) suspended from these means.
5. Raft according to any one of Claims 1 to 3, characterized in that the heaviest load or loads (10₃) are each suspended from the raft hanging means by means of a strap (13) engaged in and sliding through these means and fixed to the raft.
6. Raft according to any one of Claims 1 to 5, characterized in that the raft is an inflatable raft.

Images