The present invention relates to an offshore installation, such as a vessel, a ship, a drilling platform, a production platform, a loading and/or unloading buoy, a so-called spar, a floating body, etc., which offshore installation is provided with an emergency escape device arranged at the edge of the deck, the emergency escape device comprising an inflatable life raft, which is preferably stored in a barrel-like body, and descending means, via which a person can descend from the deck of the vessel to the water.

Such offshore installations provided with an emergency escape device are generally known. Offshore installations, in particular drilling platforms, are in practice provided with life rafts which are located on the deck close to the railings and are stored in barrel-like bodies composed of two or more shell parts. In the event of an emergency, one or more persons then have to throw the life raft overboard, the life raft inflating automatically once it hits the water. Since the deck of a drilling platform, and often also that of a ship, may be situated several to several tens of metres, such as for example thirty metres, above the water level, descending means are furthermore provided in order to descend from the deck to the water. Descending means of this kind generally comprise rope ladders or nets. These descending means are fastened by an upper end to the offshore installation and also have to be thrown overboard manually by people. In order then to descend to the water using the descending means, the people present on the platform in the emergency situation first have to climb over the railing and then descend from the railing to the water using the descending means. Throwing the life raft and the descending means over the railing into the water requires the necessary effort and frequently requires a number of passengers and/or crew to cooperate in an emergency situation. These actions are relatively time-consuming and cannot always be carried out equally easily in emergency situations. Furthermore, stepping onto the descending means from the deck, possibly after first having climbed over the railing, is difficult and, in particular in emergency situations, too time-consuming owing to the difficulty of stepping onto them and any obstacles to be overcome in the process. Moreover, accidents occur relatively frequently in emergency situations when stepping onto them.

The object of the present invention is, inter alia, to overcome

the abovementioned disadvantages. In particular, the object of the present invention is to provide an offshore installation provided with an improved emergency escape device.

The abovementioned objects are achieved according to the invention in that the emergency escape device comprises a main frame, on which the life raft and the descending means are arranged in such a manner that they can be thrown off in the event of an emergency, and in that the main frame comprises at least one stairway which, at least in the event of an emergency, extends downwards from the deck level and which, at its bottom end, adjoins the descending means. Due to the fact that the life raft and the descending means are arranged on the main frame such that they can be thrown off, they can easily be put overboard merely by removing, inactivating or breaking their support on or fastening to the main frame. It will be clear that an arrangement of this kind on the main frame allowing them to be thrown off can be achieved in a variety of manners. Thus, for example, it is conceivable to fasten the life raft and the descending means to the main frame by means of tapes. These tapes can then be uncoupled or optionally cut through in the event of an emergency using relatively simple means, after which the life raft and the descending means can fall downwards into the sea. For this purpose, the main frame should, in the event of an emergency, be situated outside the offshore installation. The main frame may in this case be situated permanently outboard but may also be moved outboard in the event of an emergency. Due to the fact that the stairway extends downwards from the deck level and at its bottom end adjoins the descending means, the accessibility of the descending means to passengers and/or crew in an emergency situation is improved. This is because they no longer have to clamber onto the descending means directly from the deck or from the railing, but rather can approach the said means via a stairway, which reduces the risk of further passengers or crew in an emergency situation hindering the efforts of a passenger or crew member attempting to step onto the descending means from the offshore installation or possibly even accidentally pushing him/her downwards owing to jostling.

In order to improve the accessibility to the emergency escape device and in particular the descending means in the event of an emergency, it is advantageous according to the invention if the main frame comprises at least one railing part, which, in the event of an emergency, adjoins the edge of the deck, having next to it an access from the deck opening onto a platform which is arranged on the main frame and,

at least in the event of an emergency, projects outwards from the edge of the deck, and if the at least one stairway begins next to the platform below the at least one railing part. As a result, the passengers or crew who are themselves trying to evacuate via the access firstly have to step onto the platform and then have to step laterally from the platform onto the stairway beginning next to the platform and below the railing part. In this way, it is therefore not necessary to climb over the railing, which is generally permanently present, before being able to reach the descending means. Furthermore, the bend introduced as a result of stepping laterally onto the stairway reduces the risk of a passenger or crew member being pushed onto the stairway too quickly, owing to the jostling which will frequently occur in emergency situations, and as a result possibly falling off the stairway and perhaps even falling onto a person situated lower down on the stairway or on the descending means. Obviously, it is particularly advantageous here if the platform is provided with a safety railing on its side remote from the deck, that is to say on its side opposite that of the access.

In order, in the event of an evacuation, to assist the passage of the passengers or crew to be evacuated, it is advantageous according to the invention if the main frame comprises two of the said railing parts with the platform between them, and if at least one stairway begins beneath each railing part on either side of the platform. The passengers or crew to be evacuated can then make use of one stairway or the other stairway turn and turn about. According to an advantageous embodiment of the invention, the main frame can be moved with a rotational and/or translational movement with respect to the offshore installation from a storage position into an escape position which is situated essentially outboard and in which the stairway extends downwards from the deck level. A main frame of this kind, which can be moved by means of a rotational and/or translational movement from a storage position into an escape position in the event of an emergency, has a number of advantages. A first advantage is that it then becomes possible to store the main frame completely inboard and to place it outboard only in the event of an emergency, so that under normal circumstances there are no additional components projecting out from the side of the offshore installation. A second advantage, separate from the first advantage, is that the rotational and/or translational movement can be used for throwing off the life raft and the descending means from the main frame, that is to say putting them overboard. This can take place in

a variety of manners. It is conceivable for a coupling by means of which the life raft and/or the descending means are fastened to the main frame to be broken under the direct influence of or during the rotational or translational movement of the main frame. However, it may also be very advantageous here according to the invention if the main frame is provided with supports which hold the life raft and the descending means in position on the main frame when this main frame is in the storage position and which allow the life raft and the descending means to be thrown down under the effect of inertial forces which they undergo during displacement from the storage position into the escape position. Throwing down the life raft and/or the descending means will be facilitated in particular if the main frame in this process undergoes a rotation or tilting.

It is particularly advantageous according to the invention if the main frame is fastened in a pivoting manner to the offshore installation, the pivot axis running essentially parallel to, and preferably close to, the edge of the deck, if the main frame is essentially horizontally oriented in the storage position with the at least one stairway projecting outboard from the deck, and if the main frame, in the emergency position, is essentially vertically oriented and lies essentially completely outboard. In this case, the main frame, in the event of an emergency, is then rotated through about 90°, so that a life raft and/or descending means supported in a horizontal storage position by the main frame can, in the vertical emergency position, be as it were thrown down automatically owing to, for example, the absence of any further support in that position, optionally assisted by the acceleration force which the inflatable raft and/or the descending means undergo as a result of the rotation or tilting of the main frame, which force furthermore releases the inflatable raft and/or the descending means from the main frame and can allow the inflatable raft and/or the descending means to slide or roll off from a part which in the escape position extends essentially horizontally.

It is particularly advantageous here, according to the invention if, viewed in the horizontal direction and considered in the storage position of the main frame, the centre of gravity or mass centre of the main frame with all its associated components, such as the roll of net and the life raft lies on the outboard side of the pivot axis, since the rotational movement of the main frame will then take place largely or entirely under the influence of a turning moment exerted on the main

frame owing to the force of gravity.

In order easily to be able to throw off the life raft and/or the descending means with a rotatably fastened main frame of this kind, it is advantageous according to the invention if the life raft and/or the descending means, in the storage state:

- have an essentially cylindrical circumferential shape;

- are arranged with their longitudinal direction essentially parallel to the axis of rotation; and

- are arranged between support rests which prevent them from rolling away to the side.

When the main frame is rotated essentially through 90° , the support rests will lose their action preventing rolling away if the life raft and/or the descending means are, as it were, placed loosely thereon, that is to say in the storage state rest thereon in a manner which does not prevent the life raft and/or the descending means from being removed upwards. The essentially cylindrical circumferential shape and the orientation of a cylindrical body of this kind with the longitudinal direction essentially parallel to the axis of rotation moreover allows rolling off when thrown down. It may be advantageous here according to the invention if the descending means are arranged on the underside of the platform, and if the life raft is arranged on the top side of the platform, and if the platform supports the life raft. With a rotatably arranged emergency escape device, the descending means can fall downwards automatically when the main frame is moved into or towards the vertical position, while the life raft can roll or slide off the platform when the main frame is in the escape position or can be rolled or slid off the said platform.

In order to be able to move the emergency escape device from its storage position into an escape position, it is advantageous in accordance with a further embodiment of the invention if the emergency escape device is provided with a locking mechanism which can be operated by means of a lever and comprises two interacting locking means, one locking part being an element which is rigidly fastened to the main frame and the other locking part being an element which is rigidly fastened to the lever, the locking means interacting in such a manner that, when the lever is operated in the event of an emergency, the main frame, before moving in the direction of the emergency position, is firstly forced to move slightly in the opposite direction. This has the advantage that if, for example, dirt, paint or tar impede setting in motion and/or moving

the main frame, this resistance is overcome more easily by firstly forcing the main frame slightly in the opposite direction, as a result of which, as it were, a levering effect is achieved. As a supplement to this, but also applicable separately, it is advantageous according to the invention if the emergency escape device is provided with a pushing mechanism which can be operated via a lever and by means of which a force which assists the movement of the main frame into the emergency position can be exerted on the said main frame. A pushing mechanism of this kind also makes it possible to overcome a starting resistance owing to, for example, dirt residues, paint and tar, and if this pushing mechanism is used together with the interacting locking parts, preferably acting after these locking parts, an extra levering effect overcoming starting resistance is achieved.

In order to stabilize the movable main frame in its escape position, so that passengers and/or crew evacuating will not be impeded by a moving main frame, it is advantageous according to the invention if the emergency escape device is provided with stop means in order to be able to stop the said device in its emergency position. It will be clear that stop means of this kind can be designed in various manners. These stop means should act in some way on the main frame situated in the escape position, for example on a rung of the stairway.

In accordance with a further advantageous embodiment of the invention, the emergency escape device is provided with four-bar mechanisms which are arranged on either side of the main frame and by means of which the main frame can be displaced from a storage position, which is situated inboard, into an emergency position, which is situated outboard. A four-bar mechanism is understood here to mean a rectangle of (imaginary) bars which are interconnected at their ends by means of joints. A four-bar mechanism of this kind forms, for example, a relatively simple way of providing an emergency escape device which in its storage position is situated entirely inboard on the offshore installation and which in the event of an emergency can be moved completely outboard. When the main frame is being moved outboard, it will describe a translation combined with a rotation in a first direction followed by a rotation in the opposite direction.

In accordance with a further embodiment of the invention, a main frame which can be displaced from a storage position, which may be situated essentially inboard, into an escape position if the emergency escape device comprises two guide tracks on either side of the main

frame, and if the main frame can be displaced along the said guide tracks from a storage position, which is situated essentially inboard, into an emergency position, which is situated essentially outboard.

In accordance with a particularly preferred embodiment of the invention, the offshore installation is a drilling or production platform or a buoy. A drilling or production platform of this kind may be supported on the (sea)bed by legs, but may also be a floating body optionally anchored by anchors.

The invention furthermore relates to an emergency escape device particularly intended for an offshore installation according to the invention.

The descending means may within the scope of the invention comprise all kinds of descending means, such as for example rope ladders, climbing nets, ropes, cables, hose-like flexible chutes, etc. According to the invention, in particular an emergency escape device and an offshore installation provided with an emergency escape device of this kind are provided in which simultaneously both throwing the life raft and the descending means down and stepping onto the descending means from the offshore installation by passengers and/or crew are considerably simplified and improved, which in emergency situations will lead to a time saving and greater safety in evacuating passengers and/or crew.

The invention will be explained in more detail in the following text with reference to a drawing, in which several embodiments are illustrated by way of example and in which:

Figure 1 shows a diagrammatic, perspective view of an emergency escape device according to the invention in the storage state;

Figure 2 shows a cross-sectional view of the emergency escape device of Figure 1, but with more details being shown; Figure 3 shows a view in accordance with Figure 2, but with the emergency escape device almost completely in the escape state;

Figure 4a shows a view in the direction of arrow IVa from Figure 2 of the emergency escape device according to the invention illustrated in Figure 2; Figure 4b shows a view in the direction of arrow IVb from

Figure 3 of the emergency escape device according to the invention illustrated in Figure 3;

Figure 5 shows a first alternative embodiment of an emergency escape device according to the invention;

Figure 6 shows a second alternative embodiment of an emergency escape device according to the invention;

Figure 7 shows a third embodiment of an emergency escape device according to the invention; and Figure 8 shows a diagrammatic top view of the emergency escape device in the escape state.

Figure 1 shows part of a deck 1 of an offshore installation, such as an oil drilling platform. The deck 1 is provided along its edge with a railing 2, which is interrupted for the provision on the offshore installation of an emergency escape device 3 according to the invention.

The emergency escape device 3 here comprises a fixed frame 4, 5 which is mounted fixedly on the deck and a main frame 7 which is fastened rotatably thereto along axis of rotation 6. The main frame 7 comprises two railing parts 8 with an access 9 between them, a platform 10 extending essentially perpendicular to the access 9. supporting brackets 11 arranged on either side, a safety railing 12, a reinforcement/support bar 13. and two stairways 15 arranged below the railing parts 8 on either side of the platform 10.

When the main frame 7 is situated in the storage state, an inflatable life raft 16 stored in a cylindrical, two-shell enclosure and a net 17 rolled up into a roll are arranged on this main frame 7. One longitudinal side of the life raft 16 bears against the platform 10 and the opposite side thereof is supported by two rest brackets 18 fastened to the railing parts 8. The net 17 rolled up into a roll is resting in a rest bracket 20 adapted to the outer circumference of the roll.

If a passenger or crew member is standing in front of the emergency escape device, he/she can move the emergency escape device 3. which is held in its storage state by a locking mechanism, into its escape state by pulling the operating lever 5 towards him/her. As will be described later, a locking mechanism 22, 24 is hereby released and the main frame 7 is made to rotate clockwise through about 90° .

Before it is possible to pull the operating lever 5 towards him/her, hook 21 first has to be uncoupled. The said locking means comprise a pin 22, which is arranged on the main frame and in this case is formed by a section of the railing part 8 and a plate 23, which is fixed to the lever 5 with respect to the lever 5 and is provided with a recess for accommodating the pin 22 , the recess being delimited at the top on its right-hand side in Figure 2 by a nose 24 which points slightly downwards. If the lever 5 is now rotated anticlockwise around axle 25.

the nose 24 will press the pin 22 slightly downwards, as a result of which the entire main frame 7 is rotated anticlockwise slightly around axis of rotation 6. This has the effect of releasing dirt or paint or tar residues present in the joint 26 (by means of which the main frame 7 is fastened to the fixed frame 4). Furthermore, a pushing mechanism 25' is provided on the plate 23, which mechanism is formed by a curved surface which, when the lever 5 is rotated sufficiently far anticlockwise, will press pin 22 upwards, in order to initiate a clockwise rotation of the main frame 7- This pushing mechanism 25 is also advantageous both on its own and in combination with the locking mechanism 22, 24 if it is necessary to overcome a starting resistance owing, for example, to dirt residues in the joint 26 in order to bring about the rotational movement of the main frame 7 into the escape position.

The locking mechanism 22 , 23. 24 and the pushing mechanism 25 are in principle superfluous if: there is no starting resistance to be overcome, and if the centre of gravity or mass centre of the main frame 7, viewed in accordance with Figure 2, is situated sufficiently far to the right of axis of rotation 6, since the force of gravity will then exert a turning moment in order to move the main frame from its storage position into the escape position.

When the main frame 7 rotates into its escape position, the roll of net will roll out of the rest bracket 20 and fall downwards. In order to effect unrolling of the roll of net and to prevent the roll of net from falling completely into the water, the roll of net is provided with cords 26 fastened to the end of the net, by means of which cords the top end of the roll of net 17 is fastened to the main frame 7 via hooks 27. It will be clear that the cords 26 may equally well be fastened to the offshore installation itself.

Furthermore, it will be clear from Figures 2 and 3 that when the main frame 7 moves into its escape position, the life raft 16 receives a horizontally directed impulse and as a result will roll off the platform 10, as indicated diagrammatically by arrow 27- In the design illustrated in Figures 1, 2, 3 and 4, it is possible to realize horizontal launching speeds for the life raft of 6 km/hour. The result of this is that the life raft will land at a certain distance away from the offshore installation, which has the additional advantage that there is less risk of passengers or crew who jump or fall off the offshore installation landing on the life raft or possibly on people already occupying the life raft, there is less risk of objects which fall off the

offshore installation striking the life raft and there is less risk of the life raft moving under the drilling platform.

When the main frame 7 moves into its escape position, a stop hook 29, which is around an axle 30 and is preloaded by a spring 28, will be able to engage around a bar, preferably a rung of the stairway 15. of the main frame, in order to fix the main frame 7 in its escape position. It can clearly be seen by referring in particular to Figure 4b that the main frame 7 is provided, on the side facing towards the offshore installation, with two railing parts 8 with an access 9 between them opening onto a platform 10. The stairway 15 with rungs 31 begins below the railing parts 8 on either side of the platform 10. These rungs 31, of which in the exemplary embodiments illustrated two are shown per stairway 15, adjoin the descending means, in the exemplary embodiment illustrated a net 17. Furthermore, it can be seen in Figure 4b that the underside of the net bracket 20 can serve as an extra handle 33 for passengers and/or crew stepping onto the descending means. Passengers and/or crew descending from the stairway onto the descending means can moreover gain support from the rungs 31 and the side brackets 11. Furthermore, it can be seen in Figure 4b that the railing bar 12 provides extra support on the outboard side of the platform 10 for passengers and/or crew stepping onto the stairway and prevents passengers and/or crew from being pushed off the platform 10.

As indicated by arrows in the diagrammatic top view of Figure 8, the railing parts 8 and the platform 10, in the event of an emergency, provide a kind of lock action, due to the fact that the route to be taken to the stairway by the passengers and/or crew forms a "bend" just before the stairway. As a result, the jostling undergone by people (passengers and/or crew) situated on the stairway(s) is reduced. This lock action and reduction in jostling are further improved by the bow 60, which acts as a kind of crush barrier and is positioned inboard in front of the access at a distance providing a passage for people and as a result of which the access 9 can only be approached from the sides, so that a further "bend" is created in the route to the stairway. Due to the fact that a stairway is provided on either side of the platform, firstly the flow of passengers and/or crew in an emergency situation is improved and secondly more space is created between successive passengers and/or crew descending on one side of the platform.

The fixed frame is furthermore provided with a grate 61 which can be walked on.

Figure 5 illustrates a very diagrammatically depicted variant embodiment of an emergency escape device according to the invention. In this variant embodiment, the movable main frame is denoted by 40. In terms of design, this movable main frame is essentially identical to the main frame 7 as described with reference to Figures 1 to 4. Details of the main frame, the life raft and the descending means are omitted for the sake of clarity. However, this main frame can be displaced from an entirely inboard storage position situated above the deck into an escape position situated entirely outboard (dot-dashed lines) by means of four- bar mechanisms arranged on either side of the main frame 40. Each four- bar mechanism in this case comprises two bars 4l and 42, which are fastened with one end pivoting on the main frame 40 and the other end pivoting on the deck 1. As will be clear from Figure 5, this side view shows only one of the four-bar mechanisms, and this four-bar mechanism, like the main frame 40, is illustrated in the storage position (solid lines), in the escape position (broken dot-dashed lines) and in an intermediate position (broken dashed lines). It can be seen here that, when moving from the storage position into the escape position, the main frame 40 firstly undergoes an anticlockwise tilting and then a clockwise tilting. This tilting to and fro can optionally be used to release the life raft and the descending means from the main frame 40, in order to be launched therefrom, under the influence of inertial forces acting on them. It will furthermore be clear to an average person skilled in the art that the four-bar mechanisms would be able to be operated in a relatively simple manner by a passenger or crew member using a lever. This lever could also be used in a relatively simple manner to uncouple the life raft and the descending means from the main frame 40 at a suitable moment during the movement of the main frame 40.

Figure 6 illustrates a second variant embodiment of an emergency escape device according to the invention. In this variant embodiment too, the movable main frame is denoted by 40, and this main frame 40 essentially corresponds to the main frame 7 from Figures 1-4. Details of the main frame, the life raft and the descending means are omitted for the sake of clarity. The main frame 40 is illustrated here in its storage position (solid lines) situated essentially but not entirely inboard above the deck 1, in its escape position (broken dot-dashed lines) and in an intermediate position (broken dashed lines). Guides 44 and 45, which are fastened to the offshore installation, are provided on either side of the main frame 40. The main frame 40 is suspended in

these guides 44 and 45 by means of pins 46 and 47- The pins 46 and 47 may equally well be wheels or rollers. As will be clear from Figure 6, the main frame 40 can be moved from the storage position into the escape position along the fixedly disposed guides 44 and 45. It will also be clear from the embodiment illustrated diagrammatically in Figure 6 that this is only a very diagrammatically illustrated principle, which an average person skilled in the art can easily develop in more detail. For example, it is conceivable for the main frame 40 to be held in its storage position by a locking mechanism and, after this locking mechanism has been unlocked, to be pushed out of the storage position into the escape position by one or more passengers or crew. This movement can also be assisted by means of a lever system, as will be clear to an average person skilled in the art. It will also be clear to an average person skilled in the art that the comments made with regard to the embodiment of Figure 5 relating to launching the life raft and the descending means and uncoupling them from the main frame 40 are also applicable to the embodiment in accordance with Figure 6.

Figure 7 very diagrammatically illustrates a third variant embodiment of an emergency escape device according to the invention. In this variant embodiment too, the movable main frame is indicated by 40, and this main frame 40 essentially corresponds to the main frame 7 from Figures 1-4. Details of the main frame have been omitted for the sake of clarity. This emergency escape device is fastened permanently to the outboard side of the deck 1 of the offshore installation. The life raft 16 and the roll of net 17 are fastened to the main frame 40 by means of safety belts 50. These safety belts 50 can easily be cut through or detached by uncoupling a coupling (not shown) . As a result of cutting through the safety belts 50 or uncoupling the couplings, the roll of net 17 will automatically fall downwards and the life raft 16 will come to rest freely on the platform 10, after which it can easily be pushed downwards by one or more passengers or crew.

It should be noted with regard to the safety belts 50 from Figure 7 that they can also very easily be used in the embodiments in accordance with Figure 5 and Figure 6 and even in the embodiments in accordance with Figures 1 to 4.

With regard to the present invention, many modifications, variants and embodiments are conceivable which fall within the essence of the invention and the scope of the claims. Thus the stairway 15 may comprise more than 2, for example 5 or 10 rungs, and the descending means may be of any type.