WO2011019289A1

WO2011019289A1 - A transport device and a method of operating the device

Info

Publication number: WO2011019289A1
Application number: PCT/NO2010/000306
Authority: WO
Inventors: Johan F. Andresen
Original assignee: Andresen Johan F
Priority date: 2009-08-14
Filing date: 2010-08-16
Publication date: 2011-02-17
Also published as: TW201111228A; AR077927A1

Abstract

The invention concerns a transport device for transferring a module (6) between a first unit (1) and a second unit (2). A first module guiding member (3; 31) is articulately attached (5) to the first unit (1), a second module guiding member (4; 32) is slidably connected to the first module guiding member. A first drive system (8) and a second drive system (9), configured for selectively moving the module along the module guiding members, and the drive systems are configured with two references connected to each respective module guiding member (3, 4; 31, 32). The two module guiding members are arranged with an overlapping region and arranged such that the module (6) is operated with respect to the one reference when it is in the first module guiding member and with respect to the other reference when it is in the second module guiding member and where the references for the drive system is changed when the module (6) is in the overlapping region.

Description

A TRANFERT DEVICE AND A METHOD OF OPERATING THE DEVICE

Field of the invention

The present device concerns a device and a method of transferring a module between a first unit and a second unit, such as transportation of personnel and goods between a floating installation and a second installation which does not follow the wave movements in the same way as the floating installation.

Background of the invention

It has for several years been a desire to use an alternative to helicopter in order to gain access to an offshore platform. It has also been a challenge to find simple solutions which - in a safe manner - may transfer people and goods from the floating vessel and up to the installations.

There are a number of concepts for accommodating the relative movements between the two units, and at the same time ensure a safe transfer. One example is disclosed in WO 2004/099606, where a structure is arranged on pillars which are anchored to the seabed, and comprise in a vertical direction a movable canal which may be lowered to a floating vessel, and where an internal lift is arranged internally in the canal. WO 96/27409 describes an evacuation system where persons are led in a canal which has the size of a human being, down into a rescue platform. The canal is separated in two parts which move in a telescoping motion with respect to one another. None of these systems provide a single solution for transferring of personnel and goods between a vessel and a platform, where the system

accommodates for the movements between the vessel and the platform so as to achieve a safe transfer between the units.

Summary of the invention

The present invention provides a solution to this. The present invention comprises a transport device for use between a vessel and a fixed or floating installation.

It is thus provided a transport device for transferring a module between a first unit and a second unit, characterized by a first module guiding member which is articulately attached to the first unit, a second module guiding member which is slidably connected to the first module guiding member; a first drive system and a second drive system, configured for selectively moving the module along the module guiding members, and wherein the drive systems are configured with two references connected to each respective module guiding member, where the two module guiding members are arranged with an overlapping region and arranged such that the module is operated with respect to the one reference when it is in the first module guiding member and with respect to the other reference when it is in the second module guiding member and where the references for the drive system is switched when the module is in the overlapping region.

In one embodiment, the drive system comprises two drive devices which are connected to respective module guiding members, and which a arranged such that when the module is in the overlapping region, they may operate in a free-wheeling mode and in an operative mode.

In one embodiment, the drive devices comprise devices whereby when a drive device changes from free-wheeling mode to operative mode, the other drive device will change from an operative mode to a free-wheeling mode.

In one embodiment, the transport device comprises means for retracting the second module guiding member into the first module guiding member. The device preferably comprises means for moving the module guiding members and the module to a parked position.

In one embodiment, the transport device comprises means for detecting the movements of the module guiding members with respect to one another, to determine the transition between the two drive systems. With this, it is possible to have a transition whereby the elevator cabin continues its movements in one direction when the drive system references are changed.

In one embodiment, each of the drive systems comprises at least one pitch rack and an electric motor. In a different embodiment, the drive system comprises winches for moving the module.

In one embodiment the transport device comprises means for guiding the

movements of the module in the vicinity of the second unit. Such means may be sensors below the system the elevator cabin, which provides for a soft landing on the vessel.

In one embodiment the first module guiding member is an outer shaft and the second module guiding member is an inner shaft, and the two shafts are

telescopically movable with respect to each other.

In one embodiment the first drive system comprises a first wire connected to the module and a winch mounted on the first unit or the first module guiding member, and the second drive system comprises a second wire connected to a the module and a winch mounted on the second module guiding member.

In one embodiment the module comprises an elevator cabin for transportation of humans and goods. The transport device is particularly useful for situations where the first unit and the second unit are separate units which are movable

independently of each other.

In one embodiment the first unit is an installation which is resting on a seabed or similar and extends above a surface of water, and wherein the second unit is a vessel which floats on in the surface of water.

It is also provided a method of transferring a module between a second unit and a first unit characterized by hoisting the module inside or along a second module guiding member which is slidably arranged with respect to a first module guiding member, until the module reaches a region where the two module guiding members overlap, and in this overlapping region changing the reference point for the module drive unit from the second module guiding member to the first module guiding member, where after the module is hoisted further up in the first module guiding member which is connected to the first unit, until the module has reached the first unit and any possible cargo is moved out of the module and over onto the first unit. The principle is that the installation has a transport device which is hanging in a universal joint in a structure such that the device has free access to the water surface and with a distance with is sufficient for a vessel to position itself below the transport device.

The transport device can be slewed by means of hydraulics or winches and be parked such that is in a safe distance from the sea, in order to avoid it being hit by large waves.

A movable access platform is also conceivable, such that the system may be used even it there are movements in the horizontal plane.

Brief description of the drawings

Embodiments of the transport device according to the invention will now be described with reference to the enclosed figures, where:

Figure 1 is a side view showing an embodiment of the transport device according to the invention, suspended in a platform, in a retracted position, above a floating vessel;

Figure IA is an enlargement of a portion of figure 1;

Figure 2 shows the transport device illustrated in figure 1 in an extended position, where a lower part of the device is in contact with the deck of the floating vessel and the elevator cabin is in an upper position;

Figure 3 corresponds to figure 2, but shows the elevator cabin in a transfer position; Figure 3 A is an enlargement of a portion of figure 3;

Figure 4 corresponds to figure 2, but shows the elevator cabin in a lower position;

Figure 5 corresponds to figure 2, and shows the elevator cabin in a position in the device;

Figure 6 corresponds to figure 2, and shows the elevator cabin in an upper position;

Figure 7 is a section drawing, along the section line B-B in figure 3A;

Figure 8 shows a second embodiment of the drive system for the elevator cabin, where the elevator cabin is suspended in a second wire;

Figure 9 shows the embodiment shown in figure 8, but the elevator cabin is suspended in a first wire;

Figure 10 shows the embodiment which is shown in figure 8, and shows the elevator cabin in a transfer position;

Figure 11 and 1 IA show a second embodiment of the transport device according to the invention, suspended in a platform, and in an extended state, where a lower part of the device is in contact with the deck of a floating vessel; and

Figure 12 shows the embodiment of figures 11 and 1 IA as seen from above, corresponding to a section of the device when the elevator cabin is in a transfer position between the upper and lower parts of the device.

Detailed description of preferential embodiments

The transport device according to the invention comprises three main parts: an outer elevator shaft 3, an inner elevator shaft 4 and an elevator cabin 6.

The inner elevator shaft 4 is telescopingly arranged in the outer elevator shaft 3, and is movable between a retracted, or parked, position (see e.g. figure 1) and an extended, or activated, position (see e.g. figure 2). The movement of the inner elevator shaft 4 in the outer elevator shaft 3 is in the illustrated embodiment caused by one or more winches 12 which are mounted on the outer elevator shaft 3 and comprises wires 12a attached to the inner elevator shaft 4.

The outer elevator shaft 3 and the inner elevator shaft 4 each have their own drive system (denoted by respective reference number 8, 9) for movement of the elevator cabin 6 up and down in the elevator shafts. The outer, or first, drive system 8 comprises in the illustrated embodiment a first pitch rack 10a which runs along the outer elevator shaft 3 and is rotatably connected to it. A first electric motor 11a, assembled on the elevator cabin 6, is connected to the first pitch rack 10a in a manner which is known in the art (via a worm gear or similar). The elevator cabin may thus be moved up and down in the outer elevator shaft 3 by means of the first electric motor and the first pitch rack.

Similarly, the inner, or second, drive system 9 comprises in the illustrated embodiment a second pitch rack 1 Ob which runs along the inner elevator shaft 4 and is rotatably connected to it. A second electric motor l ib, assembled on the elevator cabin 6, is connected to the second pitch rack 10b in a manner which is known in the art (via a worm gear or similar). The elevator cabin may thus be moved up and down in the inner elevator shaft 4 by means of the second electric motor and the second pitch rack.

When not is use, the transport device is hanging in a parked position with the inner elevator shaft 4 retracted all the way up and in the outer elevator shaft 3, and with the elevator 6 on an upper level (see figures 1 and IA).

When a vessel 2 has moved into position below the transport device, the transport device may be activated and operated by means which per se are known, e.g. by means of a remote control (not shown). Alternatively, the platform 1 may comprise stationary equipment for activation and operation of the transport device.

When the transport device is activated from a retracted (parked) position, the winches 12 will lower the inner elevator shaft 4 to an extended position, e.g. until it makes contact with the deck of the vessel 2, as shown in figure 2. In order to reduce the contact force between the transport device and the vessel, a so-called "soft- landing" system 13 may be connected to the underside of the landing plate of the inner elevator shaft 4. When the inner elevator shaft is resting on the deck of the vessel, the universal joint 5 will allow movements in the horizontal plane, while the telescoping function between the two elevator shafts will allow the vessel's vertical movements.

The transport device may advantageously be combined with a landing plate or landing platform 14 (see figure 1) on the vessel 2. By adapting the platform 14 with automatic leveling and heave compensating, the use of smaller vessels, which move more in heavy seas, may easily be used for transportation of humans and goods. The platform may be integrated into the vessel 2 or be assembled on the deck as a supplementary structure. Such tailor-made landing platform 14 may make it possible to use a fork-lift truck for loading goods into the elevator cabin 6, and will reduce the relative movements between elevator system and vessel. When the inner elevator shaft 4 is lowered down as described above, the drive systems 8, 9 are activated (e.g. by means of the remote control or the stationary equipment) in order to move the elevator cabin 6.

The first electric motor 1 Ia is operated, whereby the elevator cabin 6 is moved down in the outer elevator shaft 3, via the first pitch rack 10a. The elevator cabin 6 is lowered to the level where both drive systems 8, 9 are in contact, i.e. both the first pitch rack 1 Oa and the second pitch rack 1 Ob are in contact with their respective motors 1 la,b. The first drive system 8 (used for the outer elevator shaft 3) will hold the elevator cabin 6 stationary while the second drive system 9 (for the inner elevator shaft 4) will be free-wheeling. The drive wheel of the second motor l ib will simply follow the vertical movement of the inner pitch rack 10b which follows the movements of the vessel. Reference is made to figure 3.

In this position, the references for the elevator cabin 6 are exchanged or switched. By activating an exchange of the operation of the drive systems 8, 9, the first motor 11a for the outer elevator shaft 3 will change from being at rest (hold) to freewheeling, while the second motor 1 Ib for the inner elevator shaft 4 changes from free-wheeling to holding the elevator cabin steady (hold). This state is illustrated in figure 3A. In this manner, the elevator cabin 6 is now disconnected from the outer elevator shaft 3 and connected to the inner elevator shaft 4; hence the elevator cabin 6 is now following the movements of the vessel 2. Figure 3 A shows and enlarged section of figure 3.

In this manner, the elevator cabin 6 may by means of the second drive system 9, be moved downwards until it makes contact with the landing platform on the vessel 4 (see figure 4). When in this position, personnel and goods may be loaded and made ready for being lifted up to the installation.

In this phase, the transport device may be operated from inside the elevator cabin 6 or by means of the remote control (e.g. when transporting goods).

Figure 5 is an illustration on how the elevator cabin 6 is run up, until it again makes contact with the first pitch rack 10a for the outer elevator shaft 3 and then stops. The inner elevator shaft 4 holds the elevator cabin 6 steady (hold), while the first drive system 8 (for the outer elevator shaft 3) is free-wheeling.

At this stage a change is made (a reversal of the procedure on the way down) for each of the two drive systems such that the elevator cabin 6 after the change now is attached to and is driven by the pitch rack 10a of the outer elevator shaft 3 and is de-coupled from (the drive wheel is free-wheeling) the inner elevator shaft 4. This is illustrated in figure 5. Figure 6 is an illustration of how the elevator cabin 6 then is lifted further up to an upper position, such that items and/or persons may be taken onto the installation 1.

Then, the inner elevator shaft 4 may be retracted up and into the outer elevator shaft 3 and parked (as shown in figure 1) until the transport device is to be used again. Figure 7 is a section along the section line B-B in figure 3B and illustrates i.a. how the inner elevator shaft 4 has an opening which provides room for the first drive system 8 between the elevator cabin 6 and the pitch rack 10a of the outer elevator shaft 3. The figure also illustrates (schematically) guide rails 15 between the elevator shafts and between the elevator shafts and the elevator cabin. The entrance and exit region for the elevator cabin, with doors and mechanisms which per se are known, are denoted by the reference number 38.

Reference is now made to figure 8, 9, 10 which illustrate an alternative embodiment of the drive systems where, instead of using pitch rack for driving elevator cabin 6, a system of wires and winches are used.

As shown in figures 8, 9, 10, two wires 28, 29 are attached to the elevator cabin 6. A first wire 29 runs from the elevator cabin 6 to a winch (not shown) which is mounted at the top of the outer elevator shaft 3 or on the platform 1. A second wire 28 runs from the elevator cabin 6 to a winch 20 which is mounted on top of and on the side of the inner elevator shaft 4. The two wires (and associated winches) are used in the various phases in the transportation of the elevator cabin 6.

To be able to use the two winches in the various phases of the transportation of the elevator cabin 6, a system is configured as a part of the inner elevator shaft 4 to ensure that the second wire 28 is kept in a correct position with respect to the elevator cabin. A wire sheave 23 is held in position right above the center of the elevator cabin 6 when this is lifted from the deck of the vessel 2 and a distance up inside the inner elevator shaft 4. The wire sheave 23 is mounted on a strut 22 which is connected to the inner elevator shaft 4 via a hinged device 24.

In order to move the wire sheave 23 in the correct position with respect to the elevator cabin 6, a hydraulic cylinder 21 (or a pneumatic or electrical distance control mechanism) is used, and it is attached to the strut 22 and in the inner elevator shaft 4 by means of hinged devices 25, 26.

A further wire sheave 27 is attached to the roof of the elevator cabin 6 in order to guide the second wire when the elevator cabin 6 has moved past the winch 20 and is on its way up in the outer elevator shaft 3.

Reference is now made to figure 9, illustrating how the first wire 29 which extends to the upper winch (not shown) gradually has taken over the load from the second wire 28. The mechanism which has held the second wire 28 (which is connected to the winch 20 on top of the inner elevator shaft 4)is now de-activated in that the entire system is pulled in against the wall of the inner elevator shaft 4 such that the elevator cabin 6 is not prevented from moving past the top of the inner elevator shaft 4.

Reference is now made to figure 10, illustrating how the elevator cabin 6 has moved past the winch 20 and the second wire 28 is maintained in a slight braking action. The second wire will be paid out from the winch 20 until the elevator cabin 6 has reached the top of the outer elevator shaft 3.

Reference is again made to figure 4. In this state, the winch 20 in the lower (inner) elevator shaft 4 will hold the elevator cabin 6 with a tight second wire 28 (see figure 8, which illustrates a corresponding situation, where the elevator cabin is lowered by means of the second wire). The elevator cabin 6 thus follows the movements of the vessel 2. The first wire 29 (from the upper (outer) elevator shaft 3) is hanging freely, that is with a small or no load from caused by the elevator cabin, and will follow the movements of the elevator cabin without carrying any of the load (but only possibly with a pre-tension to prevent the winch drum from paying out too much wire and causing a slack in the wire).

Reference is again made to figure 5. In this state, when the elevator cabin 6 is lifted clear of the deck of the vessel 2, the change of winches between the two systems will take place. As in this case no pitch racks attached to the elevator shafts are used, the change between the two winch systems may take place anywhere below the top of the lower (inner) elevator shaft 4 as long as the elevator cabin 6 is lifted well clear of the deck of the vessel 2. This transition is described above, with reference to figures 8 and 9.

The sheave/block system 21,22,23,24,25,26 (described above) is attached to the lower (inner) elevator shaft 4, and ensures that the elevator cabin (the cargo) is lifted as close as possible to the horizontal centre of gravity.

With the cargo (i.e. the elevator cabin 6) hanging "midway", the first wire 29 is tightened and (gradually or instantly) takes over the load from the second wire 28 and its winch 20. When the load has been transferred completely to the first wire 29, the cargo may be lifted all the way to the top of the upper (outer) elevator shaft 3 and gain access to the installation. A corresponding, but reverse procedure is used for the transportation from the platform 1 to the vessel 2.

Figure 11, 1 IA and 12 illustrate a further embodiment of the transport device according to the invention, which comprises two telescopingly arranged elements with an external elevator cabin. Such variant may be suitable for smaller structures (windmills, vessels, etc.). Instead of two elevator shaft telescopingly arranged, as described above, this embodiment uses two "climbing towers" (e.g. truss structures), where a first (upper) structure 31 is attached directly to the platform (or installation/vessel) 1 via a universal joint 5, while a second (lower) structure 32 is connected to one side of the first structure 31 via a sliding connection. The sliding connection is of a type which per se is known.

In order to move the second structure 32 with respect to the first structure 31 (which is connected to the installation 1), a winch system or a pitch rack system is used, for example of the types described above. The universal joint 5 is preferably arranged directly above centre of gravity (CG) of the entire transport device in order to minimize lateral displacements.

As for the embodiments described above, the elevator cabin 6 will use two drive systems for operation up and down, and the elevator cabin 6 will be physically connected to, in turn, the first (upper) structure 31, then both structures 31, 32 (in the overlap region), and then only to the second (lower) structure 32.

Figure 1 IA shows that the first pitch rack 1OA is attached to the first structure 31 and that the second pitch rack 1OB is attached to the second structure 32.

Figures 1 IA and 12 also show the guide systems 37 which are used for guiding the second structure with respect to the first structure, and also shows the guide system (rails 33, 34, 35, 36) which is used for the elevator cabin 6 in relation to the two structures 31, 32.

Two motors 11 A,B are used to drive the elevator cabin 6 between the vessel 2 and the installation 1 in a manner similar to what is described above. A drive system of the type described above with reference to figure 8, 9, 10 may also be used. The elevator drive systems may be also be electrical, pneumatic, hydraulic, or similar.

Although the invention has been described with reference to drive systems comprising electric motors and pitch racks, and winch/wire systems, a skilled person will understand the also other drive systems may be used, such as hydraulic drive systems and rack-and-pinion systems.

Although the invention has been described with reference to an elevator cabin 6 for transportation of persons and goods, the transport device according to the invention shall also comprise variants where the elevator cabin is replaced by other units, such as a container, machine parts, or other items which are to be lifted between the installation and the vessel. The device according to the invention can thus replace a crane for lifting of goods to and from installations, from the sea or from vessels.

The device according to the invention may also be furnished with a bottom plate (not shown) on the lower elevator shaft 4 or the lower structure 32. The bottom plate may advantageously have inflatable elements which make it possible to land it directly on the surface of the water, i.e. independently of the vessel 2. With this, the transport device may be used for evacuating personnel from the installation 1. It is also conceivable to bring inflatable rafts in the elevator, in case of an emergency.

The device according to the invention may also be used between a large vessel and a smaller vessel, for transportation of goods and personnel.

The device according to the invention may also be used between a vessel and a quay, pier or seabed for compensating between the vertical movements of a vessel, caused by external factors such as waves (swell) and tides.

Claims

1. A transport device for transferring a module (6) between a first unit (1) and a second unit (2), characterized by

a first module guiding member (3; 31) which is articulately attached (5) to the first unit (1), a second module guiding member (4; 32) which is slidably connected to the first module guiding member; a first drive system (8) and a second drive system (9), configured for selectively moving the module along the module guiding members, and wherein the drive systems are configured with two references connected to each respective module guiding member (3, 4; 31, 32), where the two module guiding members are arranged with an overlapping region and arranged such that the module (6) is operated with respect to the one reference when it is in the first module guiding member and with respect to the other reference when it is in the second module guiding member and where the references for the drive system is switched when the module (6) is in the overlapping region.

2. The transport device of claim 1, wherein the drive system comprises two drive devices (8, 9) which are connected to respective module guiding members (3, 4; 31, 32), and which a arranged such that when the module (6) is in the overlapping region, they may operate in a free-wheeling mode and in an operative mode.

3. The transport device of claim 2, wherein the drive devices comprise devices whereby when a drive device changes from free-wheeling mode to operative mode, the other drive device will change from an operative mode to a free-wheeling mode.

4. The transport device of claim 1, further comprising means (12, 12A) for retracting the second module guiding member (4) into the first module guiding member (3).

5. The transport device of claim 4, further comprising means for moving the module guiding members and the module to a parked position.

6. The transport device of any one of the preceding claims, further comprising means for detecting the movements of the module guiding members with respect to one another, to determine the transition between the two drive systems.

7. The transport device of any one of the preceding claims, wherein each of the drive systems comprises at least one pitch rack (10a, 10b) and an electric motor (Ha, l ib).

8. The transport device of any one of the preceding claims, further comprising means (13) for guiding the movements of the module (6) in the vicinity of the second unit (2).

9. The transport device of any one of the preceding claims, wherein the first module guiding member (3) is an outer shaft and the second module guiding member (4) is an inner shaft, and wherein the two shafts are telescopically movable with respect to each other.

10. The transport device of claim 3, wherein the first drive system (8) comprises a first wire (29) connected to the module and a winch mounted on the first unit (1) or the first module guiding member (3), and wherein the second drive system (9) comprises a second wire (28) connected to a the module and a winch (20) mounted on the second module guiding member (4).

11. The transport device of any one of the preceding claims, wherein the module (6) comprises an elevator cabin for transportation of humans and goods.

12. The transport device of any one of the preceding claims, wherein the first unit (1) and the second unit (2) are separate units which are movable independently of each other.

13. The transport device of any one of the preceding claims, wherein the first unit (1) is an installation which is resting on a seabed or similar and extends above a surface of water, and wherein the second unit (2) is a vessel which floats on in the surface of water.

14. A method of transferring a module (6) between a second unit (2) and a first unit (1) characterized by hoisting the module inside or along a second module guiding member (4) which is slidably arranged with respect to a first module guiding member (3), until the module reaches a region where the two module guiding members overlap, and in this overlapping region changing the reference point for the module (6) drive unit from the second module guiding member to the first module guiding member, where after the module (6) is hoisted further up in the first module guiding member (3) which is connected to the first unit(l), until the module (6) has reached the first unit (1) and any possible cargo is moved out of the module (6) and over onto the first unit (1).