EP3814212B1

EP3814212B1 - Ship comprising a bow door arrangement and/or a bow ramp arrangement

Info

Publication number: EP3814212B1
Application number: EP19739729.2A
Authority: EP
Inventors: Johan Olofsson; Thomas Petersson
Original assignee: MacGregor Sweden AB
Current assignee: MacGregor Sweden AB
Priority date: 2018-07-19
Filing date: 2019-07-04
Publication date: 2023-12-06
Anticipated expiration: 2039-07-04
Also published as: PL3814212T3; EP4289718A3; WO2020022945A2; CN112654556A; WO2020022945A3; EP3814212C0; KR20210042917A; EP3814212A2; EP4289718A2; CN112654556B

Description

TECHNICAL FIELD

The invention relates to a ship comprising a bow door arrangement.

BACKGROUND

Roll-on/roll-off (Ro-Ro) ships and similar ships are commonly used to transport cars, trucks, other wheeled vehicles and other types of cargo. Unloading of vehicles can take place from a number of various types of ramps, for instance a bow ramp. The bow ramp of a roll-on/roll-off ship, such as for instance a ROPAX ship, are normally stowed inside the hull and are covered by bow doors.
Today's bow ramps are operated by means of bulky cylinders for deploying and stowing the bow ramp with struts supporting the bow ramp. Further, operation of today's side swinging bow doors are made by means of large hinge arms mounted on the inside of the hull. These solutions take up space inside the hull and create a limitation regarding the capacity that can be unloaded from a Ro-Ro ship.
Previously known bow ramps can be seen in for instance JP 2003 026 081 , DE20 2018 101722 U1 DE 2 723 797 and WO 01/68442 A1 .
Commercial bow doors are provided today by for instance the applicant.
Thus, improvements in the field of ships that uses bow ramps and bow doors to unload cargo is needed.

SUMMARY

An object of this invention is to provide a ship comprising a bow door arrangement that addresses the problems described above. This object is achieved by the technical features contained in the characterizing portion of independent claims 1, 13, 14, 22 and 30. The dependent claims contain advantageous embodiments, further developments and variants of the invention.
The application relates to a bow door arrangement for a ship. The bow door arrangement comprises a starboard bow door, a port bow door, first starboard and port guiding arrangements and second starboard and port guiding arrangements. Each of the first and second starboard and port guiding arrangements comprises a starboard and a port ship guide part arranged to be attached to a ship and a starboard and port bow door guide part arranged to be attached to a bow door. The ship guide parts and bow door guide parts are arranged to interact to guide the starboard and port bow doors between an open position and a closed position. The first starboard bow door guide part of the first starboard guiding arrangement is arranged on a starboard bow door top part of the starboard bow door and the second starboard bow door guide part of the second starboard guiding arrangement is arranged on a bottom part of the starboard bow door. The first port bow door guide part of the first port guiding arrangement is arranged on a port top part of the port bow door and the second port bow door guide part of the second port guiding arrangement is arranged on a port bow door bottom part of the port bow door.
Embodiment not covered by the claimed invention. The application further relates to a bow ramp arrangement for a ship comprising a bow ramp and a wire actuation system. The bow ramp comprises a first bow ramp part and a second bow ramp part. The first bow ramp part is arranged to be pivotably connected to a ship. The first bow ramp part may be separable from the second bow ramp part and pivotable relative to the second bow ramp part when engaged to the second bow ramp part according to regulations and as described in WO 96/32317 A1 . Alternatively, the first bow ramp part is fixedly engaged to and pivotable relative to the second bow ramp part. The wire actuation system comprises at least one wire and a wire actuator. The wire is connected to the wire actuator, to the second bow ramp part and to a wire actuation point adapted to be arranged in a ship. The first bow ramp part is connected to a first bow ramp actuator. The wire actuator is arranged to control the deployment of the bow ramp together with the first bow ramp actuator.
The two arrangements of the application provides for enabling a wider and/or longer bow ramp for a ship. The arrangements display synergetic effects when combined but they can also be standalone alternatives. I.e., a ship can have only one of the two alternatives in order to enable a wider and/or longer bow ramp. Having both the bow door arrangement and the bow ramp arrangement will provides a ship with the greatest benefit of the largest loading/unloading capacity through the bow.
By having a bow door arrangement according to the above, a larger bow space within a ship is made available since the hinge arms used for today's side swinging bow doors can be removed by replacing the hinge arms with first and second starboard and port guiding arrangement which to operate the opening and closing of the bow doors. Removing the hinge arms opens up the possibility to use more of the ship's width for a bow ramp as the hinge arms take up space within the bow space. Also, as the first and second starboard and port guiding arrangements are located on the top and bottom parts of the bow doors, the guiding arrangements can be moved forward and aft within the bow space, thereby enabling use of more of the bow space's length. Further, the opening of the doors can now be made in a direction essentially parallel to a length direction of the ship.
By having a bow ramp arrangement according to the above, today's struts used to support the bow ramp located on the starboard and port sides of the ramp centreline can be removed. The struts are designed to hold the weight of the second bow ramp part during deployment of the bow ramp. Using a wire that takes up considerably less space than the struts frees up bow space so that the second bow ramp part and when required, the third bow ramp part, can be made longer. The third bow ramp part will have its end closer to the first bow ramp part in the bow ramps stowed position. This allows for a longer ramp as the space previously occupied by the struts can be used to lengthen the ramp.
A ship can be provided with a bow door arrangement in order to provide flexible solutions both for construction of new ships or conversion of existing ships. The widest and longest ramp will be made possible on a ship provided with both arrangements.

Bow door arrangement

The bow door arrangement may further comprise a first drive mechanism. The first drive mechanism comprises at least one drive source and transmission. The first drive mechanism is arranged to interact with drive parts arranged on the top parts of the starboard and port bow doors in order to operate the starboard and port bow doors between the open and closed positions. The drive mechanism can be any suitable drive mechanisms known in the art, such as for instance a rack and pinion arrangement, hydraulic or electro-mechanic actuators or a wire and tackle arrangement.
The first drive mechanism may be arranged to operate the opening and closing of both the starboard and port bow doors simultaneously. The first drive mechanism may be arranged such that a single drive mechanism operates both the starboard and port bow doors. This can be achieved by having the drive source interact with the drive parts on the top parts of both the starboard and port bow doors simultaneously.
Alternatively, the first drive mechanism may comprise a first starboard drive mechanism, comprising at least one drive source and transmission, arranged to operate the starboard bow door and a first port drive mechanism, comprising at least one drive source and transmission, arranged to operate the port bow door. Depending on for instance the size of the bow doors and/or the need for individual operation of the doors, a first starboard drive mechanism arranged to interact with the drive parts of the top part of the starboard bow door and a first port drive mechanism arranged to interact with the drive parts of the top part of the port bow door can be installed.
The bow door arrangement may further comprise a second drive mechanism. The second drive mechanism comprises at least one drive source and transmission. The second drive mechanism is arranged to interact with drive parts arranged on the bottom parts of the starboard and port bow doors in order to operate the starboard and port bow doors between the open and closed positions. In some instances, such as when a first drive mechanism is not sufficient or redundancy is desired, a second drive mechanism can be installed to assist in the operation of the bow doors or to be used instead of the first drive mechanism. It is possible as an alternative to have only a first drive mechanism arranged to interact with drive parts arranged on the bottom parts of the starboard and port bow doors.
The second drive mechanism may be arranged to operate both the starboard and port bow doors simultaneously. The second drive mechanism may be arranged such that a single drive mechanism operates both the first and port bow doors. This can be achieved by having the drive source interact with the drive parts on the top parts of both the starboard and port bow doors simultaneously.
Alternatively, the second drive mechanism may comprise a second starboard drive mechanism, comprising at least one drive source and transmission, arranged to operate the starboard bow door and a second port drive mechanism, comprising at least one drive source and transmission, arranged to operate the port bow door. As for the first drive mechanism, the second drive mechanism may be arranged to operate both the starboard and port bow doors individually instead of simultaneously.
The drive parts arranged on the top and bottom parts of the respective starboard, port bow doors may be racks, and the transmissions of the respective drive mechanisms may be pinions. The drive parts may alternatively be cylinders mounts arranged on the top and bottom parts of the respective starboard and port bow doors and the transmissions of the respective drive mechanisms may be hydraulic or electro-mechanical cylinders.
A starboard top beam part of the starboard bow door and a port top beam part of the port bow door may be elevated relative the remainder of a starboard bow door top part of the starboard bow door and a port top part of the port bow door respectively. The bow door may comprise a top beam part extending outside of a vertical bow door part in a transverse direction. A top part of a bow door comprises an upper side extending to the top beam part. By having a top part that comprises two different heights, the top parts of each bow door will have a stepped configuration. The elevated portion of the top parts will run in a recess in the ceiling of the bow space. This leads to that the clear height inside the bow space between the elevated top part running in the recess and the deployed bow ramp increases when the bow doors are in an open position and loading/unloading capacity is increased.
The first and second guiding arrangements may comprise at least one torque-free guiding device arranged between the ship guide part and the bow door guide part, e.g. a wheeled trolley hanging in a spherical bearing similar to one used in an overhead crane arranged to be rotatable along all axes. By having torque-free guiding means in the first starboard and port guiding arrangements, the installation of the bow doors can be made easier since the tolerance requirements can be reduced. Further, the torque-free guiding means can be used to make sure that the load on the movable parts of the respective guiding arrangements are evenly distributed. Having the first guiding arrangement torque free, may also be beneficial when sea load forces acts on the bow doors as they reduce sea load forces transferred into the guiding arrangement.
The second starboard bow door guide part of the second starboard guiding arrangement may be arranged to fit inside a cavity of the port bow door floor. Alternatively, the second port bow door guide part of the second port guiding arrangement is arranged to fit inside a cavity of the starboard bow door floor. Depending on the design of the bow doors, in some examples, the guiding arrangement of one of the bow doors may have to fit inside a cavity in the other bow door in order for the second starboard or port guiding arrangements to have enough space to fit inside the bow space of the ship. Alternatively, both bow doors have a cavity in which the guiding arrangement of the opposite door fits.
A third distance between the first starboard guiding arrangement and the second starboard guiding arrangement and a fourth distance between the first port guiding arrangement and the second port guiding arrangement may be essentially the same. By separating the starboard and port guiding arrangements from each other, the bow doors will be stable when installed/operated and forces acting on the bow doors will be more easily taken up by the guiding arrangements than if the guiding arrangement were placed closer together. The distances between the guiding arrangements will be different depending on ship type and ship length.

Bow ramp arrangement - Embodiment not covered by the claimed invention

The bow ramp may further comprise a third bow ramp part. The second bow ramp part is pivotably connected to the third bow ramp part. The second and third ramp parts are connected to each other by a second bow ramp actuator. The wire actuator is arranged to control the deployment of the bow ramp together with the first and second bow ramp actuators. Some bow ramps may require a third bow ramp part in order to achieve the desired length of the bow ramp. This third bow ramp part is engaged to the second bow ramp part and is folded underneath the second bow ramp part in the bow ramps stowed position.
The wire actuation system may comprise a wire attachment point arranged on the second bow ramp part. The wire attachment point is arranged on the second bow ramp part, leading to that the wire is attached only to the second bow ramp part of the bow ramp.
The wire actuation point may be adapted to be arranged above the wire attachment point, when the bow ramp is deployed. The wire actuation point is used to direct the wire from the wire actuator to the ramp. The wire actuation point can be located in the ship's hull or its internal structure, such as a deck. The wire actuation point can also be located in the bow ramp, specifically in the second bow ramp part.
The wire actuator may be arranged to be located either in a ship to which the ramp is attached or in the second bow ramp part. In the ship, the wire actuator may be located in a space in the hull of a ship or in a space in or on one of its internal structure, such as a deck. The wire actuator may be one of an electrically powered winch, a hydraulically powered winch or a hydraulic cylinder with a block and tackle/jigger winch.
The second ramp part and the third ramp part may have essentially the same length. By using a wire actuation system, the second ramp part can be tilted upwards during deployment of the bow ramp. This makes a longer third bow ramp part possible that does not interfere with any obstacles within the bow space during deployment of the ramp. Also, due to that the bow space for the bow ramp has been made larger, the second and third bow ramp parts can be made of essentially the same length, thereby extending the total length of the ramp compared with today's ramp where the third part is essentially shorter than the second part due to the position of the traditionally used struts.
The wire may be arranged to be pre-tensioned in order to absorb loads acting on the bow ramp during loading/unloading of cargo. In order to reduce the force exerted on for instance a quay, dock, link span or pontoon by the bow ramp when deployed and cargo is loaded or unloaded; the wire can be pre-tensioned when the bow ramp is deployed. In this way, the wire and the wire actuator will absorb at least part of the force exerted by the ramp on the quay, dock, link span or pontoon. This can increase the maximum weight of cargo being loaded or unloaded on a quay, dock, link span or pontoon compared to today, thus leading to increased loading/unloading capacity without having to reinforce the quay, dock, link span or pontoon. Also, as deflection of the bow ramp can be reduced using pre-tensioned wires when loading cargo on the bow ramp, it is possible to use the same maximum cargo weight as today with weaker/lighter ramp structure.
The second bow ramp part may further comprise bow ramp guides arranged to interact with a ramp guide arrangement arranged to be attached to the ship. The bow ramp guides may for instance glide or roll along the ramp guide arrangement in order to control the deployment of the bow ramp and of the second bow ramp part in particular.
The invention also relates to a ship comprising a bow door arrangement t according to the above. As mentioned earlier, a ship having the combination of both the bow door arrangement and the bow ramp arrangement can be provided with the longest and broadest ramp possible. A ship comprising only a bow door arrangement can be provided with a broader ramp, although today's struts holding up the bow ramp will reduce the maximum length of the ramp. A ship comprising only a bow ramp arrangement can be provided with a longer ramp with smaller first bow ramp actuators and a lighter ramp structure.
The wire actuation point may be movable relative the wire attachment point to a position where the actuation point and the wire attachment point lie essentially in the same vertical plane, when the bow ramp is deployed. By being able to move the wire actuation point relative to the wire attachment point, the direction of the force acting on the wire attachment point, and thereby on the second ramp part, by the wire can be changed such that the force is essentially vertical. This essentially reduces the force exerted by the wire on the second bow ramp part in the horizontal direction to zero leading to that a locking arrangement between the first and second bow ramp parts can be made smaller or removed completely. Moving of the wire actuation point can take place during deployment of the bow ramp or after the bow ramp is deployed.
The ship may comprise a bow space in which the entire bow ramp fits when the ramp is stowed. Inside of the bow doors, a bow space is present in which the bow ramp is placed. When the bow ramp is stowed and the bow doors are closed, the first bow ramp part creates a watertight seal between the bow space and the rest of the ship. Also, no part of the bow ramp is placed outside of the bow doors.
The invention also relates to a method for opening bow doors on a ship. A bow door arrangement comprises a starboard bow door, a port bow door, first starboard and port guiding arrangements and second starboard and port guiding arrangements. Each of the first and second starboard and port guiding arrangements comprises a ship guide part arranged to be attached to a ship and a bow door guide part arranged to be attached to a bow door. The ship guide parts and bow door guide parts are arranged to interact to guide the starboard and port bow doors between an open position and a closed position. The first starboard bow door guide part of the first starboard guiding arrangement is arranged on a starboard bow door top part of the starboard bow door and the second starboard bow door guide part of the second starboard guiding arrangement is arranged on a starboard bow door bottom part of the starboard bow door. The first port bow door guide part of the first port guiding arrangement is arranged on a port bow door top part of the port bow door and the second port bow door guide part of the second port guiding arrangement is arranged on a port bow door bottom part of the port bow door, wherein the method comprises:

opening the starboard bow door and port bow door in a direction essentially perpendicular to a length direction of the ship.

The invention also relates to a system for a ship comprising a bow door arrangement and a bow ramp arrangement, wherein the bow door arrangement comprises a starboard bow door, a port bow door, first starboard and port guiding arrangements and second starboard and port guiding arrangements, each of the first and second starboard and port guiding arrangements comprising a ship guide part arranged to be attached to a ship and a bow door guide part arranged to be attached to a bow door, where the ship guide parts and bow door guide parts are arranged to interact to guide the starboard and port bow doors between an open position and a closed position, where the first starboard bow door guide part of the first starboard guiding arrangement is arranged on a starboard bow door top part of the starboard bow door and that the second starboard bow door guide part of the second starboard guiding arrangement is arranged on a starboard bow door bottom part of the starboard bow door, and in that the first port bow door guide part of the first port guiding arrangement is arranged on a port bow door top part of the port bow door and that the second port bow door guide part of the second port guiding arrangement is arranged on a port bow door bottom part of the port bow door, and wherein the bow ramp arrangement comprises a bow ramp and a wire actuation system, wherein the bow ramp comprises a first bow ramp part and a second bow ramp part, wherein the first bow ramp part is arranged to be pivotably connected to a ship, the first bow ramp part further being separably engageable to or fixedly engaged to the second bow ramp part and pivotable relative to the second bow ramp part when engaged to the second bow ramp part, wherein the wire actuation system comprises at least one wire and a wire actuator, wherein the wire actuator e.g. is one of an electrically powered winch, a hydraulically powered winch or a hydraulic cylinder attached to a block and tackle/jigger winch, where the wire is connected to the wire actuator, to the second bow ramp part and to a wire actuation point adapted to be arranged in a ship, and the first bow ramp part is connected to a first bow ramp actuator, wherein the wire actuator is arranged to control the deployment of the bow ramp together with the first bow ramp actuator.
Embodiment not covered by the claimed invention. The invention also relates to a method for deployment of a bow ramp on a ship, wherein a bow ramp arrangement comprises a bow ramp and a wire actuation system. The bow ramp comprises a first bow ramp part and a second bow ramp part. The first bow ramp part is arranged to be pivotably connected to a ship. The first bow ramp part is further separably engageable to the second bow ramp part or fixedly engaged to the second bow ramp part and pivotable relative to the second bow ramp part when engaged to the second bow ramp part. The wire actuation system comprises at least one wire and a wire actuator. The wire is connected to the wire actuator, to the second bow ramp part and to a wire actuation point adapted to be arranged in a ship. The first bow ramp part is connected to a first bow ramp actuator. The method comprises:

operating the first bow ramp actuator to lower the first bow ramp part to engage with the second bow ramp part,
operating the first bow ramp actuator further and adjusting the length of the wire to deploy the second bow ramp part,
operating the first bow ramp actuator further and deploying the wire to lower the engaged first and second bow ramp parts, thereby deploying the bow ramp. The method of deploying a bow ramp with a wire actuation system as described above will benefit from the same advantages as already described for the bow ramp arrangement.

Bow ramp embodiment not covered by the claimed invention. The bow ramp may further comprise a third bow ramp part wherein the second bow ramp part is pivotably connected to a third bow ramp part and the second and third bow ramp parts are connected to each other by a second bow ramp actuator, wherein the method further comprises:

operating the first bow ramp actuator and adjusting the length of the wire in order to bring the second bow ramp part to forward and upwards tilted position in which the third bow ramp part can be rotated without interfering with supports placed on the tank top deck of the ship,
operating the second bow ramp actuator such that the third bow ramp part is extended, thereby deploying the bow ramp. By increasing the clearance to the supports as indicated above, a longer third bow ramp part can be used that have a good clearance to supports placed on the tank top deck of the ship without risking interference from the supports during deployment of the third bow ramp part. The supports can be for the ramp itself or for a bow door.

Bow ramp embodiment not covered by the claimed invention. The method may further comprise:

moving the wire actuation point relative a wire attachment point on the second bow ramp part to a position where the wire actuation point and the wire attachment point lie essentially in the same vertical plane, when the bow ramp is deployed.

Bow ramp embodiment not covered by the claimed invention. The method may further comprise:
after the first and second bow ramp parts are engaged,

guiding the second bow ramp part on a ramp guide arrangement arranged in the ship by means of ramp guides arranged on the second bow ramp part,
extending the second bow ramp actuator such that the third bow ramp part is extended, wherein the second bow ramp actuator is extended after the length of the wire is adjusted but before the ramp guides leaves the ramp guide arrangement. This example will also increase the clearance to the supports making a longer third bow ramp part possible without risking interference from the supports during rotation of the third bow ramp part.

The method may further comprise:

pre-tensioning the wire after deployment of the bow ramp.

As mentioned above, the ship can be equipped with a bow door arrangement according to the description above in order to achieve the object of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 schematically shows a ship comprising a bow door arrangement and a bow ramp arrangement,
Fig. 2 schematically shows a bow section of a ship comprising a bow door arrangement and a bow ramp arrangement,
Fig. 3 schematically shows a bow section of a ship comprising a bow door arrangement and a bow ramp arrangement with the outer parts of a starboard and port bow doors removed,
Fig. 4 schematically shows a bow section of a ship comprising a bow door arrangement with the starboard bow door and port bow door in an open position,
Fig. 5 schematically shows close up views of details of the bow door arrangement,
Fig. 6 schematically shows a close up view of details of an alternative bow door arrangement,
Fig. 7 schematically shows a top down view of the bow door arrangement with the starboard bow door and port bow door in a closed position,
Fig. 8 schematically shows a top down view of the bow door arrangement when opening the starboard and port bow doors,
Fig. 9 schematically shows a top down view of the bow door arrangement with the starboard bow door and port bow door in an open position,
Fig. 10a-10d schematically shows a traditional bow ramp arrangement,
Fig. 11a-11d schematically shows a bow ramp arrangement according to a first example,
Fig. 12a-12c schematically shows a bow ramp arrangement according to a second example,
Fig. 13a-13d schematically shows a bow ramp arrangement according to third example.

DETAILED DESCRIPTION

In the description, all references to directions and coordinates, e.g. vertical, horizontal, length, width, height, upper, lower, top, bottom etc. refers to a ship-based coordinate system. This means that the coordinate system is fixed within the ship and moves with the ship's movements.
Fig. 1 schematically shows a ship 1 comprising a bow section 2 comprising a bow door arrangement 3 and a bow ramp arrangement 4. The ship 1 is for instance a roll-on/roll-off (RORO) ship arranged to carry wheeled cargo as well as other types of cargo.
Fig. 2 schematically shows the bow section 2 of the ship 1 of figure 1. The bow section 2 comprises a bow door arrangement 3 comprising a starboard bow door 5 and a port bow door 6. In this example, the ship 1 comprises a bulbous bow, but the ship 1 can also be without a bulb, i.e. comprise a differently shaped bow.
Fig. 3 schematically shows the bow section 2 of the ship 1 of figure 1 with outer surfaces of the starboard bow door 5 and port bow door 6 removed in order to display an interior bow space 7 of the bow section 2 not normally visible when the bow doors 5, 6 are closed. The bow ramp arrangement 4 is placed within the bow space 7 and comprises a bow ramp 8 and a wire actuation system (not shown). The bow ramp 8 comprises a first bow ramp part 9, a second bow ramp part 10 and a third bow ramp part 11. The wire actuation system comprises at least one wire (not shown) attached to a wire actuator (not shown), to the second bow ramp part 10 of the bow ramp 8 and to a wire actuation point (not shown) arranged in the ship 1.
In all figures, a bow ramp with a first bow ramp part, a second bow ramp part and a third bow ramp part is illustrated. However, as described above, the disclosure works just as well for a bow ramp with only a first bow ramp part and a second bow ramp part.
Fig. 4 schematically shows the bow section 2 of the ship 1 comprising the bow door arrangement 3 with the starboard bow door 5 and port bow door 6 in an open position. In figure 4, the starboard bow door 5 and the port bow door 6 have opened in an essentially straight line that is perpendicularto a length direction of the ship 1. Today's side hinged doors swing forward and outwards when opening The outer surface 12 of the starboard bow door 5 is outlined with a dash-dot line.
Fig. 5 schematically shows close up views of details of the bow door arrangement 3. The function of the starboard bow door 5 will be described in most detail. The port bow door 6 work in the same way as the starboard bow door 5 unless otherwise indicated.
The starboard bow door 5 comprises an essentially vertical starboard bow door part 13 connected to an essentially horizontal starboard bow door part 14. The starboard bow door part 13 has an essentially vertical inner edge 15 transitioning to an essentially horizontal starboard top beam part 16. The starboard bow door part 13 also has a slanted outer edge 17 essentially following the shape of the hull of the ship 1 within the bow space 7. The starboard bow door 5 comprises a starboard bow door top part 18 having a length equal to the combined length of an upper side 57 of the starboard bow door part 13 and the starboard top beam part 16. The starboard bow door top part 18 is essentially perpendicular to a length direction of the ship 1 and can be straight or curved. In the example described in the application, the starboard bow door top part 18 is straight leading to that the bow doors 5, 6 open in a direction essentially perpendicular to the length direction of the ship.
The bow door arrangement 3 comprises a first starboard guiding arrangement 19, a first port guiding arrangement 20, a second starboard guiding arrangement 22 and a second port guiding arrangement 21 arranged on the starboard bow door 5 and port bow door 6 respectively. Each of the first and second starboard guiding arrangements 19, 21 and first and second port guiding arrangements 20, 22 comprises a ship guide part 19a, 21a; 20a, 22a arranged to be attached to the ship 1 and a bow door guide part 19b, 21b; 20b, 22b arranged to be attached to the respective starboard and port bow doors 5, 6.
The first starboard ship guide part 19a and first starboard bow door guide part 19b and the second starboard ship guide part 21a and second starboard bow door guide part 21b are arranged to interact to guide the starboard bow door 5 between an open position and a closed position. The first port ship guide part 20a and first port bow door guide part 20b and the second port ship guide part 22a and second port bow door guide part 22b are arranged to interact to guide the port bow door 6 between an open position and a closed position.
The first starboard bow door guide part 19b is arranged on the starboard bow door top part 18 of the starboard bow door 5 and the second starboard bow door guide part 21b is arranged on a starboard bow door bottom part 23 of the starboard bow door 5. The first port bow door guide part 20b is arranged on a port bow door top part 24 of the port bow door 6 and the second port bow door guide part 22b is arranged on a port bow door bottom part 25 of the port bow door 6.
In this example, the starboard bow door top part 18 of the starboard bow door 5 has a shape similar to a T-beam, with the flange of the T-beam acting as the first starboard bow door guide part 19b. The flange allows for the first starboard ship guide part 19a, which is arranged to be attached to a ceiling 26 of the bow space 7, to interact with the first starboard bow door guide part 19b of the starboard bow door 5. In this example, the first starboard ship guide part 19a is a pair of wheels or rolls arranged to run along a lower side of the flange of the first starboard bow door guide part 19b. The first starboard ship guide part 19a can comprise more than one pair of wheels or rolls. Alternatively, the first starboard ship guide part 19a can be similar to the mechanism arranged to move a hoist of an overhead crane or any other similar means. Other types of guide parts can also be conceivable such as sliding pads/parts instead of wheels or rolls.
Alternatively, the examples of the first starboard bow door guide part 19b and the first starboard ship guide part 19a can be replaced by the respective counterpart. In one example, the first starboard ship guide part 19a can thus be a T-beam arranged to be attached to the ceiling 26 of the bow space 7. The first starboard bow door guide part 19b can thus be a pair of wheels or rolls attached to the starboard bow door top part 18 of the starboard bow door 5 arranged to run along an upper side of the flange of the T-beam.
In the example of figure 5, the starboard bow door top part 18 of the starboard bow door 5 is essentially straight. The first starboard guiding arrangement 19 is thus arranged such that the starboard bow door 5 moves in a direction essentially perpendicular to the length direction of the ship 1. Alternatively, the starboard bow door top part 18 of the starboard bow door 5 can be curved, with the curvature of the starboard bow door top part 18 of the starboard bow door 5 comprising one radius, at least two radii or a continuous change in radius. This leads to that the starboard bow door 5 will open along a curved path from its closed to its open position.
In its closed position, in which the starboard bow door 5 is in figure 5, the first starboard ship guide part 19a is positioned close to an outer upper edge 27 on the starboard bow door top part 18 of the starboard bow door part 13.
In order to keep the starboard bow door 5 balanced, the first starboard guiding arrangement 19 comprises a starboard balancing part 28 attached to the starboard bow door top part 18 of the starboard bow door 5 close to an inner upper edge 29 of the starboard bow door 5 and is arranged to be movable with the starboard bow door 5. The starboard balancing part 28 can for instance be a wheel or roll arranged to roll against the ceiling 26 of the bow space 7. Alternatively, sliding pads/parts can be used instead of the wheel or roll. In figure 5, this is illustrated by the port balancing part 30 of the port bow door 6 with a port top beam part 31 in dashed lines arranged behind starboard bow door top part 18 of the starboard bow door part 13 in a length direction of the ship 1.
In the starboard bow door's 5 open position, which is not shown in figure 5, the first starboard ship guide part 19a is positioned close to an inner upper edge on the starboard top beam part 16 of the starboard bow door part 13.
The starboard bow door bottom part 23 of the starboard bow door 5 is arranged to be attached to the starboard bow door part 14. The starboard bow door bottom part 23 in this example is a vertical sheet transitioning to a starboard bottom sheet part 32 extending outside of the starboard bow door part 14. The second starboard bow door guide part 21b is arranged in the starboard bow door bottom part 23. In this example, the second starboard bow door guide part 21b is a recess. The second starboard bow door guide part 21b of the starboard bow door bottom part 23 of the starboard bow door 5 is arranged to interact with the second starboard ship guide part 21a of the second starboard guiding arrangement 22. In this example, the second starboard ship guide part 21a is a set of wheels or rolls arranged to be attached to a bottom surface 34 of the bow space 7. The set of wheels or rolls are in this example separated by a distance in a direction essentially perpendicular to the ship's length direction in order to provide sufficient lever arms from the respective wheel in order to balance the starboard bow door 5. The separation between the respective wheels are determined by the width of the ship. Alternatively, the second starboard ship guide part 21a may comprise a sheet with a recess arranged in it attached to the bottom surface 34 of the bow space and the second starboard ship guide part 21a may comprise a set of wheels or rolls arranged to be attached to the starboard bow door part 14. Alternatively, sliding pads/parts instead of wheels or rolls can be used.
Figure 6 shows an alternative starboard bow door top part 18 and port bow door top part 24. In figure 6, the starboard top beam part 16 and port top beam part 31 is elevated relative the remainder of the starboard bow door top part 18 and the port bow door top part 24 respectively. One example of how much the top beam parts can be elevated is between half and one and a half top beam part height. The top beam parts 16, 31 of figure 6 are arranged to run in one recess or two recesses 26a in the ceiling 26 of the bow space 7.
Fig. 7 schematically shows a top down view of the bow door arrangement 3 with the first and second bow doors 5, 6 in a closed position. As can be seen from figure 7, the starboard bow door top part 18 of the starboard bow door 5 lie forward of the port bow door top part 24 of the port bow door 6. An example first distance L1 in the length direction of the ship between the starboard bow door top part 18 of the starboard bow door 5 and the port bow door top part 24 of the port bow door 6 is between approximately 100 and 1000 mm.
Similarly, the starboard bow door bottom part 23 of the starboard bow door 5 lie forward of the port bow door bottom part 25 of the port bow door 6. An example second distance L2 in the length direction of the ship between the starboard bow door bottom part 23 of the starboard bow door 5 and the port bow door bottom part 25 of the port bow door 6 is between approximately 100 and 1000 mm. Alternatively, the port bow door top and bottom parts 24, 25 of the port bow door 6 lie forwards of the starboard bow door top and bottom parts 18, 23 of the starboard bow door 5. Alternatively, the starboard and port bow door top beam parts 16,31 and starboard and port bow door bottom parts 23, 25 can be telescopically arranged in two or more parts in the starboard bow door 5 and port bow door 6 respectively. In this arrangement, the starboard and port bow doors 5, 6 and their respective parts are aligned, e.g. the starboard and port bow door top beam parts 16,31 abuts.
The first and second distances L1, L2 are measured from the middle of the starboard and port bow door top parts and starboard and port bottom parts respectively, as seen in a length direction of the ship. The first and second distances L1, L2 are to be seen as example distances indicative for the example ship 1 of the drawings. If a larger or smaller ship 1 should use the bow door arrangement 3, these distances are adapted accordingly.
A first drive mechanism 35 comprising a drive source and transmission is arranged to operate the starboard bow door 5 and the port bow door 6. In one example, the first drive mechanism 35 comprises a single drive mechanism operating both the starboard bow door 5 and the port bow door 6 simultaneously. The first drive mechanism 35 can be a rack and pinion arrangement arranged to interact with a starboard top drive part 36 and a port top drive part 37 arranged on the respective top parts 18, 24 of each of the starboard and port bow doors 5, 6 in order to operate both the starboard bow door 5 and the port bow door 6 simultaneously. In one example, the top drive parts 36, 37 are gear bars or "racks" arranged on an innermost side 38 of the starboard bow door part 13 and starboard top beam part 16 and an outermost side 39 of a port bow door part 58 and port top beam part 31 with a circular gear or "pinion" arranged between the starboard bow door 5 and the port bow door 6 acting as the transmission. Rotating the pinion thus operates both the starboard bow door 5 and the port bow door 6 simultaneously. Alternatively, one circular gear can be arranged to interact with the starboard top drive part 36 and one circular gear can be arranged to interact with the port top drive part 37 where the two circular gears are driven by a single drive source, thereby operating both the starboard bow door 5 and port bow door 6 simultaneously.
In another example, the first drive mechanism 35 comprises separate drive mechanisms for the starboard bow door 5 and the port bow door 6. Also in this example, the first drive mechanism 35 can be rack and pinion arrangements arranged to operate both the starboard bow door and the port bow door separately. The top drive parts can be arranged in the same way as described above, with the difference that each pinion is coupled to a separate drive source.
Alternatively, the gear bar or "rack" may be arranged on starboard and port top surfaces 40, 41 of each of the starboard and port bow doors 5, 6. One separate pinion is arranged to interact with each rack in order to operate the starboard bow door 5 and port bow door 6 separately.
The first drive mechanism 35 can be integrated into the first starboard and port guiding arrangements 19, 21 or be separate from the first starboard and port guiding arrangements 19, 21 by that the wheels or rolls described above can be replaced with pinions. Alternatively, the wheels or rolls can be motorized to operate the bow doors 5, 6. Other types of drive mechanisms, such as hydraulic cylinders or linear actuators, can provide the necessary movement by pushing and pulling the starboard bow door 5 and the port bow door 6.
In figure 7, it can also be seen that the port bow door 6 comprises a cavity 42 in which a starboard bottom sheet part 32 fits in order to provide room for the necessary length of the entire second starboard guiding arrangement 20.
Fig. 8 schematically shows a top down view of the bow door arrangement 3 when opening the bow doors. As can be seen, the starboard bow door 5 and port bow door 6 move essentially linearly outwards in a direction perpendicular to the length direction of the ship 1. As mentioned above, the movement of the starboard and port bow doors 5, 6 can also be along a curved path.
Fig. 9 schematically shows a top down view of the bow door arrangement 3 in an open position. Also in figure 9 is an outline of a bow ramp 8 of a bow ramp arrangement 4 in a stowed position.
This illustrates that the bow door arrangement 3 provides ample space for a wider and/or longer bow ramp 8.
A third distance Ls between the first starboard guiding arrangement 19 and the second starboard guiding arrangement 21 and a fourth distance Lp between the first port guiding arrangement 20 and the second port guiding arrangement 22 are essentially the same.
In the present example, the third distance Ls is between approximately 8000 mm and 10000 mm and the fourth distance Lp is between approximately 8000 mm and 10000 mm.
The third and fourth distances Ls, Lp are measured from the middle of the starboard and port bow door top parts and starboard and port bottom parts respectively, as seen in a length direction of the ship. The third and fourth distances Ls, Lp are to be seen as example distances indicative for the example ship 1 of the drawings. If a larger or smaller ship 1 should use the bow door arrangement 3, these distances are adapted accordingly.
Bow ramp embodiments not covered by the claimed invention. Fig. 10a-10d schematically show a ship 1 with a traditional bow ramp arrangement 44 close to a docking structure 45 such as a quay, dock, link span, pontoon or similar structure.
The traditional bow ramp arrangement 44 comprises a first bow ramp part 9 releasably and pivotably connectable to a second bow ramp part 10. As an alternative, the first bow ramp part 9 may be fixedly and pivotably connected to the second bow ramp part 10 The second bow ramp part 10 is in turn pivotably connected to a third bow ramp part 11. The traditional bow ramp arrangement 44 further comprises at least one strut 46 connected to the second bow ramp part 10.
In figure 10a, the traditional bow ramp arrangement 44 is in its stowed position ready to be deployed. As indicated by the left-most arrow, the first bow ramp part 9 is operated by means of a first bow ramp actuator 47 that lowers and raises the first bow ramp part 9. The first bow ramp actuator 47 can comprise one or more actuators. The first bow ramp part 9 is arranged to engage with the second bow ramp part 10 when lowered. The separation of the first bow ramp part 9 and the second bow ramp part 10 is in one example of compliance to industry regulations and enables the first bow ramp part 9 to act as a watertight seal. This is shown in all the following figures. The first bow ramp part 9 and the second bow ramp part 10 may also be fixedly engaged to each other in another compliance example, this is not shown further. As indicated by the right-most arrow, the third bow ramp part 11 is ready to be deployed. This motion is made by a second bow ramp actuator (not shown) connecting the second bow ramp part 10 and the third bow ramp part 11, see also WO 96/32317 A1 . The second bow ramp part 10 is held in place by the at least one strut 46 attached to the bottom surface 34 of the bow space 7 of the ship 1. The at least one strut 46 guides the movement of the second bow ramp part 10 and thereby the entire bow ramp 8 during deployment and stowing of the bow ramp 8. Normally, two struts 46 are attached to the second bow ramp part 10 on either side of the bow ramp 8 centreline.
In figure 10b, the first bow ramp part 9 and the second bow ramp part 10 have engaged and the third bow ramp part 11 has been partially deployed. In this position, the first bow ramp actuator 47 continues to lower the first bow ramp part 9, which now connected to the second bow ramp part 10, result in the lowering of the entire bow ramp 8.
In figure 10c, the bow ramp 8 has been lowered further and is ready to be laid against the docking structure 45.
In figure 10d, the bow ramp 8 is fully deployed and a ramp flap 48 connected to the third bow ramp part 11 rests against the docking structure 45. The bow ramp 8 rests on bow ramp hinges located on the bottom surface 34 of the bow space 7 of the ship 1. Bow door supports 49 placed on the tank top deck of the ship 1 are also illustrated in the figure.
From this position, a great amount of force needs to be provided by the first bow ramp actuator 47 in order to raise the bow ramp 8 due to the short lever arm. This requires the first bow ramp actuator 47 to be sized accordingly in order to be able to provide the force required and results in that the first bow ramp actuator 47 can be take up a lot of space. Further, the short lever arm for the first bow ramp actuator 47 to raise the bow ramp 8, and the short lever arm for the struts 46 to prevent the second and third bow ramp parts 10, 11 to rotate around the hinges connecting the first and second bow ramp parts, result in high forces acting on ramp structure and ship structure.
Bow ramp embodiments not covered by the claimed invention. Fig. 11a-13d schematically show a bow ramp arrangement 4 according to a first, second and third example of the present solution. The bow ramp arrangement 4 comprises a bow ramp 8 and a wire actuation system 50. The various examples of figures 11a-13d can be used separately or be combined in order to reach the desired effect of providing a longer bow ramp that can open within the bow space.
In all examples of the bow ramp arrangement 4, the bow ramp 8 comprises a first bow ramp part 9, a second bow ramp part 10 and a third bow ramp part 11. The first bow ramp part 9 is arranged to be pivotably connected to a ship 1 and further being separable from the second bow ramp part 10 and pivotable relative to the second bow ramp part 10 when engaged to the second bow ramp part 10 or being fixedly engaged to the second bow ramp part 10. The second bow ramp part 10 is pivotably connected to a third bow ramp part 11. A ramp flap 48 may be pivotably connected to the third ramp part 11.
The wire actuation system 50 comprises at least one wire 51 and a wire actuator 52. The wire 51 is connected to the wire actuator 52, to the second bow ramp part 10 and to a wire actuation point 53 adapted to be arranged in the ship 1. The wire actuation point 53 is arranged to redirect the wire from a wire attachment point 54 on the second bow ramp part 10 to the wire actuator 52.
The first bow ramp part 9 is connected to a first bow ramp actuator 47 and the second and third bow ramp parts 10, 11 are connected to each other by a second bow ramp actuator (not shown). The wire actuator 52 is arranged to control the deployment of the bow ramp 8 together with the first bow ramp actuator 47 and the second bow ramp actuator.
In the figures, the wire actuator 52 is illustrated by a winch attached to the ship 1. The placement of wire actuator 52 in the figures is for illustrative purposes only. The wire actuator 52 is normally placed within the ship's structure or in the second bow ramp part 10 as indicated by the dashed outline in the figure. The wire actuator 52 may alternatively be an electrically powered winch, a hydraulically powered winch or a hydraulic cylinder controlling the actuation of the wire 51. A block and tackle system/jigger winch may be incorporated into the wire actuation system 50 in order to control the forces exerted by the wire actuator 52 and achieve the required stroke on the cylinder to deploy the bow ramp 8 completely.
Figure 11a schematically shows the bow ramp arrangement of the first example is in its stowed position ready to be deployed. Similar to the traditional bow ramp arrangement 44, a first bow ramp actuator 47 operates the first bow ramp part 9. In this example, the third bow ramp part 11 is essentially equal in length to the second bow ramp part 10, making the entire bow ramp 8 longer than in the traditional bow ramp arrangement 44 where the third bow ramp part 11 is shorter than the second bow ramp part 10 due to the location of today's used struts.
In figure 11b, the first bow ramp part 9 has engaged with the second bow ramp part 10. The wire 51 allows for the second bow ramp part 10 to be held in a more upright position that is different from the position of the second bow ramp part 10 of the traditional bow ramp arrangement 44 during deployment of the bow ramp 8. This is due to that the first bow ramp actuator 47 push the second bow ramp part 10 while the second bow ramp part 10 hang in the wire 51 and consequently moves forward and upwards during an initial phase of deployment of the bow ramp 8 and thereby create more space for the lengthened third bow ramp part 11 as illustrated by the outline in figure 10b. As can be seen, the third bow ramp part 11 does not collide with the bow door supports 49 during deployment. Having a longer third bow ramp part 11 in the traditional bow ramp arrangement 44 would have resulted in that the third bow ramp part 11 would have been hindered during deployment by the bow door supports 49.
In figure 11c, the third bow ramp part 11 is fully deployed and the bow ramp 8 is ready to be lowered onto the docking structure 45.
In figure 11d, the bow ramp 8 is completely deployed. From this position, when the bow ramp 8 is to be stowed, the wire 51 will assist in lifting the bow ramp 8 and will provide most of the lift required to lift the bow ramp 8. This leads to that the first bow ramp actuator 47 can be made smaller as it does not have to provide the same amount of force as for the traditional bow ramp arrangement 44.
Fig. 12a-12c schematically show a bow ramp arrangement 4 according to a second example. In the second example, the wire actuation point 53 is movable in a direction essentially parallel to the length direction of the ship 1.
As illustrated in figure 12a, the wire actuation point 53 is movable to a forward position from a rear position. In figure 12a, the bow ramp 8 is partly deployed, and the wire actuation point 53 is located above the wire attachment point 54 but not in the same vertical plane as the wire attachment point 54. As the bow ramp 8 is not fully extended, the second bow ramp part 10 will move outwards during its deployment, leading to that the wire actuation point 53 will be located at a distance horizontally from the wire attachment point 54. If the wire actuation point 53 not was movable forward in the length direction of the ship 1, it would have resulted in a horizontal force component acting on the second bow ramp part 10 by the wire 51. This horizontal force component is unwanted and tries to open the hinges between first bow ramp part 9 and second bow ramp part 10 if no pushing force is applied from the first bow ramp actuator 47, or if no locking device is used between the first bow ramp part 9 and the second bow ramp part 10. This is also the case in figures 11a-11d.
In figure 12b, the bow ramp 8 is almost deployed and the wire actuation point 53 has reached its forward position.
In figure 12c, the bow ramp 8 is fully deployed and the wire attachment point 54 is in a position where the wire attachment point 54 and the wire actuation point 53 lie essentially in the same vertical plane. This results in that the forces acting on the second bow ramp part 10 are directed essentially only vertically, with essentially no force component in the horizontal direction. As the horizontal force is removed or at least greatly reduced, this reduces the need for locking of the second bow ramp part 10 relative to the first bow ramp part 9 or reduces the need of pushing force from the first bow ramp actuator 47 in order to prevent opening of the first 9 and second 10 ramp hinge.
Fig. 13a-13d schematically show a bow ramp arrangement 4 according to third example. In the third example, the bow ramp arrangement 4 comprises a ramp guide arrangement 55 arranged to be attached to the ship 1. The second bow ramp part 10 comprises ramp guides 56 attached to the second bow ramp part 10 that can interact with the ramp guide arrangement 55.
In fig 13a, the bow ramp 8 has started to deploy. As can be seen from the figure, the second bow ramp part 10 is guided by the ramp guides 56 interaction with the ramp guide arrangement 55. The ramp guides 56 can be anything that can glide or roll on a surface, e.g. a glide surface or wheels or rolls attached to the second bow ramp part 10.
In fig. 13b, the second bow ramp part 10 has reached a position similar to the position in fig. 10b. The ramp guides 56, the ramp guide arrangement 55 and the wire 51 interact to bring the second bow ramp part 10 into a more upright position in which the third bow ramp part 11 can be deployed without interfering with the bow door supports 49.
In fig. 13c, the third bow ramp part 11 has been partly deployed. As can be seen by the outline in fig. 13c, the third bow ramp part 11 does not collide with the bow door supports 49 as would have been the result if the upright position not was reached before rotating the third bow ramp part 11.
In fig. 13d, the bow ramp 8 is fully deployed and rests on the docking structure 45.
In the above examples, the length of the first bow ramp part is between 4 and 10 m, the length of the second bow ramp part is between 5 and 10 m and the length of the third bow ramp part is between 2 and 10 m.
Reference signs mentioned in the claims should not be seen as limiting the extent of the matter protected by the claims, and their sole function is to make the claims easier to understand.
As will be realised, the invention is capable of modification in various obvious respects, all without departing from the scope of the appended claims. Accordingly, the drawings and the description thereto are to be regarded as illustrative in nature, and not restrictive.
As mentioned above, the combination of the bow door arrangement and the bow ramp arrangement will provide a ship with the longest and widest ramp possible. However, a ship comprising either of the bow door arrangement or the bow ramp arrangement will be able to utilize the advantages provided by each separate arrangement.
Further, all distances mentioned above are indicative of the example ship of the drawings. Depending on the final design of a ship, the distances are adapted accordingly.

Claims

A bow door arrangement (3) for a ship (1), wherein the bow door arrangement (3) comprises a starboard bow door (5), a port bow door (6), first starboard and port guiding arrangements (19, 21) and second starboard and port guiding arrangements (20, 22), each of the first and second starboard and port guiding arrangements (19, 21; 20, 22) comprising a ship guide part (19a, 21a; 20a ,22a) arranged to be attached to a ship (1) and a bow door guide part (19b, 21b; 20b, 22b) arranged to be attached to a bow door (5, 6), where the ship guide parts (19a, 21a; 20a ,22a) and bow door guide parts (19b, 21b; 20b ,22b) are arranged to interact to guide the starboard and port bow doors (5, 6) between an open position and a closed position, characterized in that the first starboard bow door guide part (19b) of the first starboard guiding arrangement (19) is arranged on a starboard bow door top part (18) of the starboard bow door (5) and that the second starboard bow door guide part (21b) of the second starboard guiding arrangement (21) is arranged on a starboard bow door bottom part (23) of the starboard bow door (5), and in that the first port bow door guide part (20b) of the first port guiding arrangement (20) is arranged on a port bow door top part (24) of the port bow door (6) and that the second port bow door guide part (22b) of the second port guiding arrangement (22) is arranged on a port bow door bottom part (25) of the port bow door (6).
The bow door arrangement (3) according to claim 1, further comprising a first drive mechanism (35), the first drive mechanism (35) comprising at least one drive source and transmission, wherein the first drive mechanism (35) is arranged to interact with top drive parts (36, 37) arranged on the top parts (18, 24) of the starboard and port bow doors (5, 6) in order to operate the starboard and port bow doors (5, 6) between the open and closed positions.
The bow door arrangement (3) according to claim 2, wherein the first drive mechanism (35) is arranged to operate the opening and closing of both the starboard and port bow doors (5, 6) simultaneously.
The bow door arrangement (3) according to claim 2, wherein the first drive mechanism (35) comprises a first starboard drive mechanism, comprising at least one drive source and transmission, arranged to operate the starboard bow door (5) and a first port drive mechanism, comprising at least one drive source and transmission, arranged to operate the port bow door (6).
The bow door arrangement (3) according to any one of claims 2-4, further comprising a second drive mechanism, the second drive mechanism comprising at least one drive source and transmission, wherein the second drive mechanism is arranged to interact with drive parts arranged on the bottom parts (23, 25) of the starboard and port bow doors (5, 6) in order to operate the starboard and port bow doors (5, 6) between the open and closed positions.
The bow door arrangement (3) according to claim 5, wherein the second drive mechanism is arranged to operate both the starboard and port bow doors (5, 6) simultaneously.
The bow door arrangement (3) according to claim 5, wherein the second drive mechanism comprises a second starboard drive mechanism, comprising at least one drive source and transmission, arranged to operate the starboard bow door (5) and a second port drive mechanism, comprising at least one drive source and transmission, arranged to operate the port bow door (6).
The bow door arrangement (3) according to any one of claims 2-7, wherein the top drive parts (36, 37) are racks and the transmissions are pinions, or the top drive parts (36, 37) are cylinders mounts and the transmissions are hydraulic or electro-mechanical cylinders.
The bow door arrangement (3) according to any one of the preceding claims, wherein a starboard top beam part (16) of the starboard bow door (5) and a port top beam part (31) of the port bow door (6) is elevated relative the remainder of a starboard bow door top part (18) of the starboard bow door (5) and a port bow door top part (24) of the port bow door (6) respectively.
The bow door arrangement (3) according to any one of the preceding claims, wherein the first starboard and port guiding arrangements (19, 20) comprises at least one torque-free guiding device arranged between the ship guide part (19a, 20a) and the bow door guide part (19b, 20b), e.g. a wheeled trolley hanging in a spherical bearing.
The bow door arrangement (3) according to any one of the preceding claims, wherein the second starboard bow door guide part (21b) of the second starboard guiding arrangement (21) is arranged to fit inside a cavity (42) of the port bow door floor, or the second port bow door guide part (22b) of the second port guiding arrangement (22) is arranged to fit inside a cavity (42) of the starboard bow door floor (14).
The bow door arrangement (3) according to any one of the preceding claims, wherein a third distance (Ls) between the first starboard guiding arrangement (19) and the second starboard guiding arrangement (21) and a fourth distance (Lp) between the first port guiding arrangement (20) and the second port guiding arrangement (22) are essentially the same.
A method for opening bow doors (5, 6) on a ship, wherein a bow door arrangement (3) comprises a starboard bow door (5), a port bow door (6), first starboard and port guiding arrangements (19, 21) and second starboard and port guiding arrangements (20, 22), each of the first and second starboard and port guiding arrangements (19, 21; 20, 22) comprising a ship guide part (19a, 21a; 20a ,22a) arranged to be attached to a ship (1) and a bow door guide part (19b, 21b; 20b, 22b) arranged to be attached to a bow door (5, 6), where the ship guide parts (19a, 21a; 20a ,22a) and bow door guide parts (19b, 21b; 20b ,22b) are arranged to interact to guide the starboard and port bow doors (5, 6) between an open position and a closed position, the first starboard bow door guide part (19b) of the first starboard guiding arrangement (19) is arranged on a starboard bow door top part (18) of the starboard bow door (5) and that the second starboard bow door guide part (21b) of the second starboard guiding arrangement (21) is arranged on a starboard bow door bottom part (23) of the starboard bow door (5), and in that the first port bow door guide part (20b) of the first port guiding arrangement (20) is arranged on a port bow door top part (24) of the port bow door (6) and that the second port bow door guide part (22b) of the second port guiding arrangement (22) is arranged on a port bow door bottom part (25) of the port bow door (6), wherein the method comprises:
- opening the starboard bow door (5) and port bow door (6) in a direction essentially perpendicular to a length direction of the ship (1).
A ship (1) comprising a bow door arrangement (3) according to any one of the claims 1-12.
A system for a ship (1) comprising a bow door arrangement (3) and a bow ramp arrangement (4),
wherein the bow door arrangement (3) comprises a starboard bow door (5), a port bow door (6), first starboard and port guiding arrangements (19, 21) and second starboard and port guiding arrangements (20, 22), each of the first and second starboard and port guiding arrangements (19, 21; 20, 22) comprising a ship guide part (19a, 21a; 20a ,22a) arranged to be attached to a ship (1) and a bow door guide part (19b, 21b; 20b, 22b) arranged to be attached to a bow door (5, 6), where the ship guide parts (19a, 21a; 20a ,22a) and bow door guide parts (19b, 21b; 20b ,22b) are arranged to interact to guide the starboard and port bow doors (5, 6) between an open position and a closed position, where the first starboard bow door guide part (19b) of the first starboard guiding arrangement (19) is arranged on a starboard bow door top part (18) of the starboard bow door (5) and that the second starboard bow door guide part (21b) of the second starboard guiding arrangement (21) is arranged on a starboard bow door bottom part (23) of the starboard bow door (5), and in that the first port bow door guide part (20b) of the first port guiding arrangement (20) is arranged on a port bow door top part (24) of the port bow door (6) and that the second port bow door guide part (22b) of the second port guiding arrangement (22) is arranged on a port bow door bottom part (25) of the port bow door (6), and wherein the bow ramp arrangement (4) comprises a bow ramp (8) and a wire actuation system (50), wherein the bow ramp (8) comprises a first bow ramp part (9) and a second bow ramp part (10), wherein the first bow ramp part (9) is arranged to be pivotably connected to a ship (1), the first bow ramp part (9) further being separably engageable to or fixedly engaged to the second bow ramp part (10) and pivotable relative to the second bow ramp part (10) when engaged to the second bow ramp part (10), wherein the wire actuation system (50) comprises at least one wire (51) and a wire actuator (52), wherein the wire actuator (52) e.g. is one of an electrically powered winch, a hydraulically powered winch or a hydraulic cylinder attached to a block and tackle/jigger winch, where the wire (51) is connected to the wire actuator (52), to the second bow ramp part (10) and to a wire actuation point (53) adapted to be arranged in a ship (1), and the first bow ramp part (9) is connected to a first bow ramp actuator (47), wherein the wire actuator (52) is arranged to control the deployment of the bow ramp (8) together with the first bow ramp actuator (47).