NO345400B1

NO345400B1 - Anchoring system for a gangway end portion

Info

Publication number: NO345400B1
Application number: NO20190411A
Authority: NO
Inventors: Trond Edvard Hystad
Original assignee: Hystad Prosjekt As
Priority date: 2019-03-26
Filing date: 2019-03-26
Publication date: 2021-01-18
Also published as: NO20190411A1; WO2020197410A1

Description

ANCHORING SYSTEM FOR A GANGWAY END PORTION

The invention concerns an anchoring system for releasably securing an end portion of a heave compensated gangway to a landing platform.

When connecting two floating vessels or a floating vessel and an installation projecting above a sea level with a gangway, heave motion of the one or two vessels induced by waves, water currents etc. will cause a projecting end portion of the gangway to move relative to the installation or floating vessel onto which the end portion is to dock. Actuator systems arranged for manoeuvring the gangway may be heave compensated, thus reducing the relative movement of the gangway end portion versus the landing. However, there is still a need of assisting the landing of the gangway end at the landing platform. It is a benefit to connect the gangway end to the landing platform while there is still a gap between the gangway end and the landing platform for improved control of the docking of the gangway end.

The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art, or at least to provide a useful alternative to prior art.

The object is achieved through features, which are specified in the description below and in the claims that follow.

An anchoring system is provided, wherein a catching structure is arranged at a landing platform, the catching structure being provided with a guide extending from a mouth portion at an outer edge of the catching structure to a bottom portion of the guide. The guide is preferably V-shaped. A narrow aperture is extending from the bottom portion of the guide further into the landing platform. The inner, narrow aperture is at each side defined by an anchor securing means extending downwards from the bottom face of the catching structure. The portion of the landing platform defining the guide is preferably slanted, descending from the bottom portion of the guide.

An end portion of a gangway is provided with an anchor arrangement wherein a longitudinal element, typically a wire or a rope, the longitudinal element, hereinafter named “rope”, being connected to an actuator arranged to extend and retract said longitudinal element. In a preferred embodiment the rope is passing over a drawwork, wherein a first multisheave block section is firmly attached to a gangway framework close to the outermost end of the gangway, while a second multi-sheave block section is displaceable arranged in the framework further from the outermost end of the gangway, the displacement being performed by an actuator, typically a hydraulic cylinder or another type of linear actuator. At the outermost end of the gangway the rope is passing over a guide pulley. At the outermost end of the rope an anchor body is attached. The anchor body may have a spherical cross section, having the form of a ball, a cylindrical body, a barrel-shaped body or the like, arranged to engage with the anchoring securing means at the aperture of the catching structure of the landing platform when the portion of the rope extending from the gangway end has been conveyed into the aperture via the guide and thereafter retracted by the drawwork. By the retraction of the rope, the anchor body is lifted till it touches the catching structure. Further retraction of the rope will cause the gangway to be pulled towards the landing platform, the gangway end finally touching the landing platform, the gangway end being secured to the catching structure of the landing platform.

A fender, a cushion or the like is preferably arranged facing downwardly from the end portion of the gangway to form a yielding contacting face between the gangway end and the landing platform.

In one embodiment the guide pulley at the gangway end is attached at an end of a rod axially displaceably arranged in the gangway. In a preferred embodiment the rod is connected to the second multiblock section, thus being displaced by the drawwork actuator synchronously with the extension or retraction of the rope. Thus, the rope is extended and the rod is simultaneously displaced to its fully protruding state, causing the anchor being located far from the gangway end, thus reducing the risk of the gangway colliding with the landing platform or surrounding structures during an initial phase of the anchoring procedure. As the rope is retracted, the rod is displaced to its inner, retracted position causing the anchor to arrive at a position close to the end of the gangway.

The rod might be made of a resilient material allowing the guide pulley to flex during the docking operation.

The invention is defined by the independent patent claim. The dependent claims define advantageous embodiments of the invention.

More specifically, the invention relates to an anchoring system for releasably securing an end portion of a heave compensated gangway to a landing platform, wherein the anchoring system comprises

an anchor arrangement comprising

an elongated, spoolable element having a first end portion, and hanging down from said end portion of the gangway;

an anchor body attached to the first end portion of the elongated, spoolable element ; and

a drawwork connected to the spoolable element and located in the gangway, the drawwork being arranged to lower and lift the anchor body;

the landing platform which comprises:

a catching structure arranged to engage with the anchor body, the catching structure comprising a guide tapering from a mouth portion of the guide at a platform edge to a bottom portion of the guide, from which a longitudinal aperture is extending with a transverse width smaller than a minimum width of the anchor body and anchor securing means located at each side of said aperture facing downwards and arranged to support the anchor body, preventing the anchor body from being displaced towards the mouth portion when in contact with the landing platform, wherein

the anchor arrangement further comprises:

a guide pulley forming an exit for the elongated, spoolable element from the gangway;

a linear actuator; and

a rod having an end portion which is attached to the guide pulley and which is axially displaceable in the longitudinal direction of the gangway by means of the linear actuator.

The guide may be V-shaped.

A landing platform structure defining the guide may be slanted, descending from the bottom portion of the guide.

The anchor body may have a spherical cross section.

The drawwork may comprise a first multi-sheave block section firmly attached to the gangway, and a second multi-sheave block section arranged displaceable in the gangway, said second multi-sheave block section being connected to a linear actuator.

A guide pulley forming an exit for the elongated, spoolable element from the gangway, may be attached at an end portion of a rod which is axially displaceable in the longitudinal direction of the gangway.

The rod may be attached to the second multi-sheave block section. Alternatively, the rod may be attached to a rod actuator separated from the second multi-sheave block section.

The rod may be made of a resilient material.

The drawwork may be arranged to apply an adjustable pull force on the rope during docking of the gangway to the landing platform.

In the following is described examples of preferred embodiments illustrated in the accompanying drawings, wherein:

Fig. 1 is a side view of a gangway anchoring system wherein an end portion of a gangway is provided with a first embodiment of an anchor arrangement, a landing platform for the gangway is provided with a catching structure arranged to catch, secure and release the anchor, the gangway end portion approaching at the landing platform;

Fig. 2 is a ground view of the landing platform;

Fig. 3 is a side view of the gangway end portion being docked at the landing platform, the gangway being attached to the landing platform by the anchoring system of the gangway and the catching system of the landing platform;

Fig. 4 is a side view of a second embodiment of an anchor arrangement, wherein a guide pulley is provided at an end portion of a resilient, axially displaceable rod, the rod being displaced to an extracted, outer position; and

Fig. 5 is a side view of the second embodiment of the anchor arrangement,

wherein the guide pulley rod and the anchor is retracted.

In the drawings an end portion 11 of a gangway 1 is depicted. A fender or cushion 111 is provided at a bottom face of the gangway end portion 11. The gangway end portion 11 is arranged to land on a landing platform 3, see figure 1 and 3. The gangway 1 is operated by appropriate means (not shown), for example a hydraulic system or a winch system provided with heave compensation means (not shown) and arranged to apply an upright lifting force component at the gangway end portion 11 during a docking of the gangway 1 at the landing platform 3.

An anchor arrangement 2 is integrated in the gangway end portion 11. A longitudinal element 22 in the form of a rope or the like, hereinafter named rope, is provided with an anchor body 221 attached at a first end of the rope 22. The anchor body 221 is preferably a ball, however various shapes, for example cylindrical barrel shaped bodies may be used. The anchor arrangement 2 comprises a drawwork 23 arranged to extend and retract the portion of the rope 22 extending from the gangway end portion 11. The rope 22 is passing over a guide pulley 21 supported in the gangway end portion 11 and is further passing over sheaves 233 of a first multi-sheave block section 231 firmly attached to the gangway 1 and sheaves 233 of a second multi-sheave block section 232 displaceably supported in the gangway 1, the displacement being performed by a linear actuator 235, preferably in the form of a hydraulic cylinder or the like. The second multi-sheave block section 232 is located further away from the guide pulley 21 than the first multi-sheave block section 231. A second end of the rope 22 is connected to a rope attachment provided in the gangway 1. By displacing the second multi-sheave block section 232 relative the first multi-sheave block section 231, the anchor body 221 can be quickly lowered and raised relative the gangway end section 11.

The anchor arrangement 2 may include one or more safety devices arranged for disconnecting the gangway 1 from the landing platform 3 in an emergency situation. In figure 1 is shown a weak link 222 connecting the anchor body 221 and the longitudinal element 22, the weak link 222 arranged to disconnect the anchor body 222 from the longitudinal element 22 in case the anchor arrangement 2 is overloaded. An additional or alternative safety device in the form of an anchor emergency release system 223 can also be provided, arranged to release the anchor body 221 and a portion of the longitudinal element 22 from the gangway 1 by cutting the longitudinal element 22 operating the anchor emergency release system 223 manually or automatically.

It is now referred to figure 2 and 3. The landing platform 3 is provided with a catching structure 31 arranged to catch and hold the first end portion of the rope 22 and the anchor body 221. A mouth portion 3111 of a V-shaped guide 311 is directed towards the gangway 1. An oblong, narrow aperture 3113 is extending from a bottom portion 3112 of the guide 311, arranged to allow the rope 22 to pass. At each side of the aperture 3113 and facing downwards anchor securing means 312 are provided, formed to prevent the anchor body 221 from sliding away from the aperture 3113 when contacting a bottom face of the landing platform 3. In order to ease the guiding of the rope 22 and the anchor body 221 into engagement with the landing platform 3, the portion of the landing platform 3 defining the V-shaped guide is slanted, slightly descending from the aperture 3113. The securing means 312 are formed to easily free the anchor body 221 from the catching structure by the gravity when the rope 22 is extended during undocking.

A second embodiment of the anchor arrangement 2 is depicted in figures 4 and 5. The guide pulley 21 of the gangway end portion 11 is arranged in an end portion of a guide pulley rod 211 which is displaceable in the longitudinal direction of the gangway 1. The rod 211 is supported by a rod guide 212 and is connected to an actuator, preferably the linear actuator 235 of the second multi-sheave block section 232 as shown in figures 4 and 5. The rod 211 is preferably made of a resilient material to allow the guide pulley 21 to flex when displaced away from the gangway end portion 11 in an initial stage of docking the gangway 1 at the landing platform 3.

During the docking the rope 22 is guided into the aperture 3113 by manoeuvring the gangway 1 using the proper manoeuvring means like propelling systems of a vessel (not shown) on which the gangway 1 is located and the manoeuvring means (not shown) included in the gangway. When located inside the aperture 3113, the rope 22 is retracted by the drawwork 23 causing the anchor body 221 to engage with the bottom face of the landing platform 3 and the anchor securing means 312, thereby forcing the drawwork 23 to pull the gangway end section 11 to land on the landing platform 3. With the embodiment depicted in figures 4 and 5, the guide pulley 21 is displaced to its inner position at the gangway end section 11 as shown in figure 5 by the rod 211 being displaced by the linear actuator 235. By connecting the rod 211 to the second multi-sheave block section 232 for displacing the rod 211 by the block section actuator 235, the displacement of the rod 211 and the extension/retraction of the rope 22 is automatically synchronized. If a separate linear rod actuator (not shown) is used for the displacement of the rod 211, the extension/retraction of the rope 22 and the displacement of the rod 211 may be operated individually.

When the gangway 1 is to be released from the landing platform 3, the procedure disclosed above is reversed.

The pull force applied on the rope 22 by the drawwork 23 during the docking is preferably adjustable to maintain a controlled anchoring force acting on the gangway, thus allowing the rope 22 to be extended if the heave compensation means (not shown) of the gangway 1 fails, without releasing the anchor body 221 from the catching structure 31 of the landing platform 3.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

C l a i m s

1. An anchoring system for releasably securing an end portion (11) of a heave compensated gangway (1) to a landing platform (3), wherein the anchoring system comprises:

an anchor arrangement (2) comprising:

- an elongated, spoolable element (22) having a first end portion, and hanging down from said end portion (11) of the gangway (1);

- an anchor body (221) attached to the first end portion of the elongated, spoolable element (22); and

- a drawwork (23) connected to the spoolable element (22) and located in the gangway (1), the drawwork (23) being arranged to lower and lift the anchor body (221);

the landing platform (3) which comprises

- a catching structure (31) arranged to engage with the anchor body (221), the catching structure (31) comprising a guide (311) tapering from a mouth portion (3111) of the guide (311) at a platform edge (32) to a bottom portion (3112) of the guide (311), from which a longitudinal aperture (3113) is extending with a transverse width smaller than a minimum width of the anchor body (221) and anchor securing means (312) located at each side of said aperture (3113) facing downwards and arranged to support the anchor body (221), preventing the anchor body (221) from being displaced towards the mouth portion (3111) when in contact with the landing platform (3);

c h a r a c t e r i s e d i n that the anchor arrangement (2) further comprises:

a guide pulley (21) forming an exit for the elongated, spoolable element (22) from the gangway (1);

a linear actuator (235); and

a rod (211) having an end portion which is attached to the guide pulley (21) and which is axially displaceable in the longitudinal direction of the gangway (1) by means of the linear actuator (235).

2. The anchoring system according to claim 1, wherein the guide (311) is V-shaped.

3. The anchoring system according to claim 1 or 2, wherein a portion of the landing platform (3) defining the guide (311) is slanted, descending from the bottom portion (3112) of the guide (311).

4. The anchoring system according to any of the preceding claims, wherein the anchor body (221) has a spherical cross section.

5. The anchoring system according to any of the preceding claims, wherein the drawwork (23) comprises

a first multi-sheave block section (231) attached to the gangway (1), and a second multi-sheave block section (232) arranged displaceable in the gangway (1), said second multi-sheave block section (232) being connected to the linear actuator (235).

6. The anchoring system according to claim 5, wherein the rod (211) is attached to the second multi-sheave block section (232).

7. The anchoring system according to claim 5, wherein the rod (211) is attached to a rod actuator separated from the second multi-sheave block section (232), said rod actuator being arranged to axially displace the rod (211) in the longitudinal direction of the gangway (1).

8. The anchoring system according to any of the preceding claims, wherein the rod (211) is made of a resilient material.

9. The anchoring system according to any of the preceding claims, wherein the drawwork (23) is arranged to apply an adjustable pull force on the elongated, spoolable element (22) during docking of the gangway (1) to the landing platform (3).