Asymetric towing staple

Abstract

A vessel for towing is disclosed, comprising a hull comprising a deck, two propulsion systems arranged along the central longitudinal axis of the hull and a towing staple for guiding a towline. The towing staple comprises outer and inner towline stoppers, arranged between the two propulsion systems for engaging with the towline during towing procedure.

Description

[0001] ASYMETRIC TOWING STAPLE

[0002] Field of the Invention

[0003] The present invention relates to the field of tugboats, tugs or vessel for towing, comprising a hull and a towing assembly, said towing assembly further comprising a towing staple assembly for a hull of said tugboat, tug or towing vessel. The present invention further relates to a hull for a tugboat, tug or a vessel for towing, comprising said towing staple.

[0004] Background of the Invention

[0005] A vessel for towing, such as a tugboat or tug, is a secondary boat that is used for maneuvering other, typically larger, vessels by pushing or pulling them either by direct contact or by means of one or more tow line. T ugs / tugboats / vessels for towing typically move vessels that either are restricted in their ability to maneuver on their own, such as ships in a crowded harbor or a narrow canal, or vessels that cannot move by themselves, such as barges, disabled ships, log rafts, or oil platforms.

[0006] Without the help from a more nimble and maneuverable towing vessel / tugboat, larger ships, such as mega-ships, would not be able to, or at least have difficulties, getting into a port.

[0007] There are different types of tugboats / towing vessels, with different types of propulsion systems and pulling characteristics, such as the conventional tugboat, the tractor tug and the so-called azimuth stern drive tug.

[0008] Tugboats may use their propulsion system and / or hydrodynamic characteristics of the hull to generate forces for maneuvering the towed vessel. Tugboats may operate in a direct towing mode or an indirect towing mode. During direct mode operations a towing force on the towline is produced, due to a pull of the tugboat's propulsion system. Therefore, operations such as stopping or reducing the towed vessel's initial movement, or assisting the towed vessel during steering, is performed by keeping the tugboat either parallel to the towed vessel's centerline or open to the corresponding side of the towed vessel.

[0009] During indirect towing, which may also be referred to as dynamic towing, the tugboat usually trails the towed vessel and exerts forces on the towed vessel for turning and / or decelerating the towed vessel. The tugboat's propulsion system may be used to place and maintain the hull of the tugboat in an angled position in relation to the towed vessel. Thereby, hydrodynamic forces will be created by the tugboat or towing vessel's hull acting against the direction of travel of the towed vessel. By positioning the side, such as a starboard or port side, of the tugboat against the direction of travel of the towed vessel the hull of the tugboat will provide a large surface acting against the flow direction of the water thereby generating drag forces which may be transmitted to the towed vessel for turning and / or decelerating the towed vessel. Decelerating and / or steering is controlled by the tug by maintaining a reference angle corresponding to the water flow direction, as opposed to the direction taken by the towed vessel. The port side is the side of the vessel which is to the left of an observer facing the bow, that is, facing forward towards the direction the vessel is heading when underway, and the starboard side is to the right side of such an observer.

[0010] A tugboat's towing equipment is a crucial link for transferring forces generated by the tugboat to the towed vessel. The towing equipment may comprise various elements which may vary between different types of tugboats. These elements are in the simplest versions just a towing bit and towline or a towing hook and towline. The towing equipment may however also comprise a towing winch, a fairlead, the towline, and / or towing pins. Each element of the towing equipment must be strong enough or designed in such a way that it can cope with the high forces generated in the towline. Due to the high forces the towline is typically heavy and strong. A failure of any of the elements in the towing equipment may lead to the towline suddenly snapping or sweeping over a deck of the tugboat, which may cause injuries to crew members working on the deck of the tugboat.

[0011] A further crucial aspect of a towing vessel / a tugboat performance, including maneuverability, stability and towing force and speed, is the location of the towing point. Within the present application, the towing point shall be interpreted as the point or location on the tugboat where the forces from the towing procedure are applied by the towline, that is the location of the towing forces of the towline on the towing vessel / tugboat during a towing procedure. The towing point is commonly regarded as the point where the towline leaves the tugboat in a straight line towards the vessel to be towed.

[0012] The location of the towing point and thereby the point where the majority of the tugging or towing forces are applied on the towing vessel / tugboat, has a major influence on the towing vessel’s / tugboat’s properties. This includes the towing vessel’s / tugboats’ overall manoeuvring ability, the available pulling force, pulling speed and the towing vessel’s / tugboats’ stability or risk for capsizing.

[0013] It is known that the location of the towing point may vary between different types of towing vessel’s / tugboats, depending on the towing vessel’s / tugboat’s design, including the propulsion system of the vessel for towing / tugboat, its steering properties and the positions utilized during pulling. The location of a towing point may vary for the same towing vessel / tugboat, depending on the actual towing procedure.

[0014] The danger with towing using a towline is the risk of girting and capsizing of the towing vessel or tugboat. Girting may happen when the towline comes at right-angles to the tugboat, e.g., during indirect towing when the hull of the tugboat is positioned perpendicular to the towed vessel. If the towline is secured around amidships of the tugboat and position at a right angle to the tugboat, then the towline under tension will exert a heeling moment on the tugboat. As with any vessel which heels over to one side, such as the starboard or port side, due to an external force, a righting lever may be formed as a center of buoyancy of the tugboat moves towards a center of the tugboats underwater volume, countering the heeling moment and pushing the tugboat back upright again. However, if the force in the towline is sufficiently powerful, it may overcome the tugboat's righting lever which may lead to deck-edge immersion of water, flooding and capsizing, which may also be referred to as girting, unless the towline is released in good time. Girting may occur very rapidly, and incidents have occurred where crew members have not been able to escape in time.

[0015] WO2011 / 139154 A2 discloses a towing device comprising two propulsion systems arranged along the longitudinal direction of the vessel, where the tow point is arranged between the first and the second propulsion system, for increased stability during indirect pulling, but without disclosing where on the longitudinal line between the two propulsion systems the tow point should be placed or how to achieve a beneficial towing point, for not only increased stability and but also efficiency of the towing device.

[0016] WO2021 / 156252 A1 discloses a hull for a vessel for towing, comprising a towing staple, or a towing structure for guiding a towline, comprising a guiding element having a symmetrical extension in a first plane parallel to the deck, comprising a towline guiding surface facing the deck, such that the towline can freely move along a periphery of the main section of the towing staple in the first plane while being restricted in movement by the main section in a direction perpendicular to the first plane, thereby controlling the vertical movement of the towing forces, by keeping the towing forces closer to the deck of the vessel for increased stability, however, the publication does not consider the effect of the horizontal placement of the towing force or towing point on the stability, nor the effect that the towing point has on the utilization of the propulsion system of the towing vessel and towing efficiency of the towing vessel.

[0017] Accordingly, there is a need for a towing solution, which mitigate, alleviate or address the shortcomings of the existing towing solutions, while providing a reliable and cost- effective solution for towing which reduces the risk of failure while fully utilizing the power of the tug.

[0018] Object of the Invention

[0019] It is an objective of the present invention to improve the stability and efficiency of the prior art towing vessels / tugboats.

[0020] A further objective of the present invention is to provide a hull for a towing vessel / tugboat comprising a towing staple constructed to control and optimize the placement of the towing points of a towing vessel / tugboat with a forward propulsion system and a reward propulsion system aligned along the central longitudinal axis of the hull of the towing vessel / tugboat, wherein the towing staple is constructed for optimizing the placement of the towing points in relation to the placement of the two propulsion systems during different towing procedures, that is a hull for a towing vessel / tugboat comprising a towing staple constructed to control and optimize the location where the towing forces act on the towing vessel / tugboat in relation to the forward propulsion system and the reward propulsion system during both direct, semidirect and indirect towing procedure.

[0021] A further objective of the present invention is to provide a hull for a towing vessel / tugboat with a forward propulsion system and a reward propulsion system aligned along the central longitudinal axis of the hull, comprising a towing staple constructed to control and optimize where the application of the towing forces act on the towing vessel / tugboat, that is the location of the towing point, during both direct and semi-direct towing procedure, wherein the towing staple is further constructed for controlling and optimizing the placement of the towing point / s in relation to the placement of the two propulsion systems, by ensuring that the towing point is placed relatively centrally between the forward propulsion system and the reward propulsion system and in close proximity to the longitudinal axis between the two propulsion systems of the towing vessel / tugboat for full utilization of the force of both propulsion systems and less interference between the forward propulsion system and the reward propulsion system.

[0022] A further objective of the present invention is to provide a hull for a towing vessel / tugboat comprising a towing staple constructed to control and optimize where the towing forces act on the towing vessel / tugboat during indirect towing, ensuring that during indirect towing, the towing point placement in relation to the forward propulsion system and the reward propulsion system is such that the towing forces applied through the at least one towline on the hull rotates the towing vessel / tugboat, such that the angle between the central longitudinal axis (A) of the hull and the at least one towline is not 90 degrees, thereby ensuring safe failure mode.

[0023] Description of the Invention

[0024] One objective of the invention is achieved by providing a hull for a vessel for towing / tugboat, comprising

[0025] - a deck;

[0026] - a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems separated by a distance (D) and aligned along the central longitudinal axis of the hull;

[0027] - at least one winch comprising at least one towline; and

[0028] - a towing staple for guiding the at least one towline, wherein the towing staple comprises:

[0029] - two outer towline stoppers, mounted to the hull;

[0030] - a support element comprising a forward mounting section mounted to the hull and a rearward mounting section mounted to the hull, the rearward mounting section comprising a guiding element mounted to the hull by means of the two outer towline stoppers, the guiding element extending between the two outer towline stoppers in a first plane substantially parallel to the deck arranged for allowing the towline to move freely along the periphery of the guiding element between the two outer towline stoppers; and

[0031] - one or more inner towline stopper, mounted to the hull arranged laterally amidships, centrally on or in close proximity to the longitudinal axis of the hull, the one or more inner towline stopper arranged for engaging with the at least one towline extending from the at least one winch towards the guiding element and / or one of the two outer towline stoppers; wherein one or more inner towline stopper is arranged between the forward propulsion system and the reward propulsion system on and / or in close proximity to the central crosswise axis of the hull.

[0032] Accordingly, it is one object of the present invention to provide a vessel for towing or a tugboat, comprising a hull comprising a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems separated by a distance (D) and aligned along the central longitudinal axis of the hull, the hull further comprising a towing staple comprising one or more inner towline stoppers, wherein the one or more inner towline stopper is arranged as to position the towing point of the towing vessel / tugboat between the forward propulsion system and the reward propulsion system during a towing procedure wherein the at least one towline exits the towing vessel / tugboat in the periphery of the guiding element, thereby ensuring that the towing point is placed between the forward propulsion system and the reward propulsion system in close proximity to central crosswise axis of the towing vessel / tugboat. This placement of the towing point in close proximity to the central crosswise axis of the towing vessel / tugboat, ensures that there is a distance between each of the two propulsion system and the towing point, thereby providing two lever arms from the pivot point of the centrally placed towing point to the point of force, created by the two propulsion systems, thereby creating a torque for considerably increased utilization of the force of the two propulsion systems.

[0033] It is an further object of the present invention to provide a vessel for towing / a tugboat, comprising a hull comprising a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems separated by a distance (D) and aligned along the central longitudinal axis of the hull, the hull further comprising a towing staple comprising one or more inner towline stoppers, wherein the one or more inner towline stoppers or one of the two outer towline stoppers are arranged as control the location where the main towing forces are applied on the towing vessel during different towing procedures in relation to the two propulsion systems. The one or more inner towline stoppers or one of the two outer towline stoppers of the towing staple are specifically constructed and arranged as to control and optimize location of the towing point, such that the placement of the towing point differs in relation to both the forward propulsion system and the reward propulsion system for different towing procedures. Thus, the present invention provides a towing staple wherein the one or more inner towline stoppers or one of the two outer towline stoppers are utilized for flexible solutions for optimizing the placement of the towing point in relation to the placement of both the forward propulsion system and the reward propulsion system and the applied towing procedure. The present invention provides a towing staple, constructed to enable different towing points for different towing procedures, such as direct, semi-direct and indirect towing procedures, wherein the towing staple is constructed as to optimize the relation between the towing point and the two propulsion systems for optimal stability of the tugboat, optimal utilization of the force of the two propulsion systems during different towing procedures and optimal safe failure mode.

[0034] Another advantage of placing the towing point between the forward propulsion system and the reward propulsion system during a towing procedure wherein the at least one towline exits the vessel / tugboat in the periphery of the guiding element is less interference between the forward propulsion system and the reward propulsion system.

[0035] Accordingly, it is another object of the present invention to provide a method of using hull according to the invention for bollard pull, wherein one of the outer towline stoppers is arranged such as to create the towing point of the towing vessel / tugboat, ensuring that during bollard pull, the pulling forces applied through the at least one towline on the hull rotates the towing vessel / tugboat, such that the angle between the central longitudinal axis (A) of the hull and the at least one towline is not 90 degrees, thereby ensuring safe failure mode.

[0036] The hull for a vessel for towing / tugboat provided by the present invention thereby provides a towing staple wherein the one or more inner towline stoppers or one of the two outer towline stoppers are arranged as control and optimize the location where the main towing forces are applied on the towing vessel / tugboat during different towing procedures in relation to the forward propulsion system and the reward propulsion system and thereby optimize the placement of the towing point of the tugboat for different towing procedures in relation to the forward propulsion system and the reward propulsion system. The towing staple provided by the present invention, thus controls and optimizes the placement of the towing point by utilizing the arrangement of the towline stoppers, such that the towing point is always placed between the two propulsion systems during different towing procedures. It is highly beneficial for both the stability and efficiency of the towing vessel / tugboat to place the towing point between the forward propulsion system and the reward propulsion system while in close proximity to the central crosswise axis of the hull. This placement of the towing point in close proximity to the central crosswise axis of the vessel / tugboat, ensures that there is a distance between each of the two propulsion system and the towing point, thereby providing two lever arms from the pivot point of the centrally placed towing point to the two force points of the two propulsion systems, thereby creating a torque for considerably increased utilization of the force of the two propulsion systems. Furthermore, the central placement of the towing point results in less interference between the two propulsion systems, as the arrangement of the towline stoppers and thereby the placement of the towing point results in the towing vessel / tugboat automatically arranging itself at an angle, such that interference between the two propulsion systems is minimized.

[0037] Another advantageous effect of the arrangement of the towline stoppers and thereby the placement of the towing point between the two propulsion systems, in close proximity to the central crosswise axis of the hull of the towing vessel / tugboat, is that the towing vessel / tugboat will have better navigation ability and improved manoeuvring properties during a towing procedure.

[0038] Yet another highly beneficial effect of the arrangement of the towline stoppers and thereby the placement of the towing point between the two propulsion systems, in close proximity to the central crosswise axis of the hull of the towing vessel / tugboat, is that such placement of the towing point considerably increases the righting movement / moment or stability of the towing vessel / tugboat, especially during indirect high-speed towing procedure, wherein the towline will extend upward from the towing vessel / tugboat and the placement of the towing point, between the two propulsion systems, in close proximity to the central crosswise axis of the hull of the towing vessel / tugboat will increase the righting movement / moment capabilities of the vessel / tugboat, thereby correcting or counteracting any cap-sizing.

[0039] Yet another advantageous effect of the arrangement of the towline stoppers and the utilization of the towline stoppers, both the inner and the outer towline stoppers for controlling and optimizing the location of the towing point, is that the placement of the towing point between the two propulsion systems, in close proximity to the central crosswise axis of the hull of the towing vessel / tugboat, results in a improved equilibrium position, that is the position that the towing vessel / tugboat returns to or seeks during shut down, failure of towline or save failure, during disruption of towing procedure. The equilibrium position is the position that the towing vessel / tugboat seeks or wants, and is also the staring position, when the towing vessel / tugboat is running or driving at low speed / engine power. The equilibrium position is the position that the towing vessel / tugboat will return to or align to, during failure, such as snapping of the towline and / or engine failure.

[0040] Another advantageous effect of the arrangement of the towline stoppers, both the two outer towline stoppers and the one or more inner towline stopper, is the how the different towline stoppers control and optimize the placement of the towing point in relation to the two propulsion systems, ensuring that the towing point is always placed between the two propulsion systems and in close proximity to the central crosswise axis of the hull of the towing vessel / tugboat during different towing procedures;

[0041] During indirect towing, the towline engages with one of the outer towline stoppers, thereby placing the towing point at the location of the outer towing stopper engaging with the towline.

[0042] During direct towing, the towline will exit the tugboat between the two outer towline stoppers without engaging with either of the two outer towline stoppers, while the towline will engage with one or more of the inner towline stoppers, thereby placing the towing point at the location of the one or more inner towline stopper engaging the towline.

[0043] The effect of the arrangement or location of the towline stoppers between the two propulsion systems and thereby the placement of the towing point in relation to and between the two propulsion systems, in close proximity to the central crosswise axis of the hull of the towing vessel / tugboat provides a combination of different advantages, resulting in a towing vessel / tugboat with superior properties, both during pulling or pushing.

[0044] The present invention provides a towing staple wherein the one or more inner towline stoppers or one of the two outer towline stoppers are arranged as control the location where the main towing forces are applied on the towing vessel during different towing procedures in relation to the two propulsion systems. The one or more inner towline stoppers or one of the two outer towline stoppers of the towing staple are specifically constructed and arranged as to optimize the different placement of the towing point in relation to both the forward propulsion system and the reward propulsion system for different towing procedures. Thus, the present invention provides a towing staple wherein the one or more inner towline stoppers or one of the two outer towline stoppers are utilized for flexible solution for optimizing the placement of the towing point in relation to the placement of both the forward propulsion system and the reward propulsion system and the applied towing procedure. The present invention provides a towing staple, constructed to enable different towing points for different towing procedures, such as direct, semi-direct and indirect towing procedures, wherein the towing staple is constructed as to optimize the relation between the towing point and the two propulsion systems for optimal stability of the tugboat and optimal utilization of the force of the two propulsion systems during different towing procedures.

[0045] The present invention provides a vessel for towing, comprising a hull, the hull comprising a forward propulsion system and a reward propulsion system aligned along the central longitudinal axis of the hull, the hull further comprising a towing staple constructed to control the placement of the towing points of a towboat, the towing staple comprising a guiding element and one or more inner towline stopper, wherein the one or more inner towline stopper is arranged between the forward propulsion system and the reward propulsion system in close proximity to central crosswise axis of the vessel, wherein the one or more inner towline stopper is constructed as to position the towing point of the towing vessel between the forward propulsion system and the reward propulsion system during a towing procedure wherein the at least one towline exits the vessel in the periphery of the guiding element.

[0046] The present invention provides a towing staple, wherein one or more inner towline stopper creates the towing point during a towing procedure wherein the at least one towline exits the vessel in the periphery of the guiding element and wherein the one or more inner towline stopper is constructed for controlling and optimizing the placement of the towing the towing point between the forward propulsion system and the reward propulsion system in close proximity to central crosswise axis, thus ensuring that there is a distance between each of the two propulsion system and the towing point.

[0047] The present invention provides a towing staple, constructed to place the towing point at a distance from and between the two propulsion systems, thereby constructing positive arms or a levers from each propulsion system to the towing point, and wherein the two positive arms or a levers separating the towing point from the two propulsion system results in a tugboat with considerably increased secured maneuvering abilities and stability, wherein control, maneuverability and stability are ensured even if one of the two propulsion systems malfunction, as the other propulsion system will still provide a force at a distance from the towing point, thus enabling control over the tugboat, for increased security and maneuverability.

[0048] Furthermore, the central placement of the towing point results in less interference between the two propulsion systems, as the arrangement of the towline stoppers and thereby the placement of the towing point results in the towing vessel automatically arranging itself at an angle, such that interference between the two propulsion system is minimized.

[0049] The two points of force created by the two propulsion system are thereby separated by said positive arms / levers from the centrally placed towing point, resulting in a tugboat where each propulsion system can be said to be point of force, separated by a lever arm from the pivot point of the centrally placed towing point, thereby creating a torque for considerably increased utilization of the force of the two propulsion systems.

[0050] In one embodiment of the present invention, a vessel for towing / tugboat is provided comprising a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, and a towing staple wherein the relation between the one or more inner towline stopper and the two propulsion systems is such that the one or more inner towline stopper is arranged between the two propulsion systems along or in close proximity to the central longitudinal axis (A) of the towing vessel / tugboat and wherein the one or more inner towline stopper is furthermore arranged closer to the central crosswise axis (B) of the hull than the reward propulsion system.

[0051] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with a longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, and a towing staple comprising one or more inner towline stopper, wherein the relation between the one or more inner towline stopper and the two propulsion systems is such that the one or more inner towline stopper is arranged between the two propulsion systems along or in close proximity to the central longitudinal axis (A) of the towing vessel / tugboat such that the distance between one or more inner towline stopper and the central crosswise axis (B) of the hull is 25% or less, such as 20%, 15%, 12.5%, 10% or 8% or less of the longitudinal length (L) of the hull.

[0052] In one embodiment of the present invention, a vessel for towing / tugboat is provided comprising two propulsion systems arranged along the central longitudinal axis (A) of the vessel / tugboat, a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems separated by a distance (D), the towing vessel / tugboat further comprising a towing staple comprising two outer towline stoppers, wherein the relation between the two outer towline stoppers and the two propulsion systems is such that the two outer towline stoppers are arranged between the two propulsion systems closer to the central crosswise axis (B) of the hull than the reward propulsion system.

[0053] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with a longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems separated by a distance (D), the vessel / tugboat further comprising a towing staple comprising two outer towline stoppers, wherein the relation between the two outer towline stoppers and the two propulsion systems is such that the two outer towline stoppers are arranged between the two propulsion systems such that the distance between any of the two outer towline stoppers and the central crosswise axis (B) of the hull is 25% or less, such as 20%, 15%, 12.5%, 10% or 8% or less of the longitudinal length (L) of the hull.

[0054] In one embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems separated by a distance (D), the hull further comprising a towing staple comprising one or more inner towline stopper and two outer towline stoppers arranged between the two propulsion systems, wherein the relation between the two propulsion systems and all the towline stoppers, that is both the two outer towline stoppers and the one or more inner towline stopper, is such that wherein the longitudinal length (L) of the hull is divided into two equal halves each spanning 50 percent of the longitudinal length (L) of the hull, the one or more inner towline stopper and the two outer towline stoppers are arranged between the two propulsion systems and within the first half or 50% of the longitudinal length (L) of the hull from the central crosswise axis (B).

[0055] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems separated by a distance (D), the hull further comprising a towing staple comprising one or more inner towline stopper and two outer towline stoppers arranged between the two propulsion systems, wherein the relation between the two propulsion systems and all the towline stoppers, that is both the two outer towline stoppers and the one or more inner towline stopper, is such that wherein the longitudinal length (L) of the hull is divided into four equal lengths, each spanning one-fourth or 25% or 25 percent of the total longitudinal length (L) of the hull and wherein the one or more inner towline stopper is arranged between the two propulsion systems and within the first one-fourth that is 25% or 25 percent of the total longitudinal length (L) of the hull from the central crosswise axis (B).

[0056] In yet another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat, the hull further comprising a forward propulsion system arranged at the forward of the hull, and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), the hull further comprising a towing staple comprising one or more inner towline stopper and two outer towline stoppers arranged between the two propulsion systems, wherein the relation between the two outer towline stoppers, the one or more inner towline stopper and the two propulsion systems is such that wherein the longitudinal length (L) of the hull is divided into four equal lengths, each spanning one-fourth or 25% or 25 percent of the total longitudinal length (L) of the hull, and wherein the one or more inner towline stopper and the two outer towline stoppers are arranged between the two propulsion systems and within the first one-fourth that is 25% or 25 percent of the total longitudinal length (L) of the hull from the central crosswise axis (B).

[0057] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat, the hull further comprising a forward propulsion system arranged at the forward of the hull, and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising one or more inner towline stopper and two outer towline stoppers arranged between the two propulsion systems, wherein the relation between the two outer towline stoppers, the one or more inner towline stopper and the two propulsion systems is such that wherein the longitudinal length (L) of the hull is divided into eight equal lengths, each spanning one-eight or 12.5% or 12.5 percent of the total longitudinal length (L) of the hull and wherein the one or more inner towline stopper is arranged between the two propulsion systems and within the first one-eight or 12.5% or 12.5 percent of the total longitudinal length (L) of the hull from the central crosswise axis (B).

[0058] In yet another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat, the hull further comprising a forward propulsion system arranged at the forward of the hull, and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising one or more inner towline stopper and two outer towline stoppers arranged between the two propulsion systems, wherein the relation between the two outer towline stoppers, the one or more inner towline stopper and the two propulsion systems is such that wherein the longitudinal length (L) of the hull is divided into four equal lengths, each spanning one-fourth or 25% or 25 percent of the total longitudinal length (L) of the hull, and wherein the one or more inner towline stopper and the two outer towline stoppers are arranged between the two propulsion systems and within the first one-eight or 12.5% or 12.5 percent of the total longitudinal length (L) of the hull from the central crosswise axis (B).

[0059] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat, the hull further comprising a forward propulsion system arranged at the forward of the hull, and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising one or more inner towline stopper and / or two outer towline stoppers arranged between the two propulsion systems, wherein the relation between the two outer towline stoppers, the one or more inner towline stopper and the two propulsion systems is such that the one or more inner towline stopper and / or the two outer towline stoppers are arranged between the two propulsion systems at a distance (D) rearwardly between the central crosswise axis (B) of the hull and the stern of the hull, and wherein the distance (D) between the central crosswise axis (B) and the one or more inner towline stopper and / or the two outer towline stoppers is less than the distance between the stern and the one or more inner towline stopper and / or the two outer towline stoppers.

[0060] In one embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising one or more inner towline stopper and / or two outer towline stoppers arranged between the two propulsion systems, wherein the relation between the two outer towline stoppers, the one or more inner towline stopper and the two propulsion systems is such that the one or more inner towline stopper and / or the two outer towline stoppers are arranged between the two propulsion systems at a distance (D) rearwardly between the central crosswise axis (B) of the hull and the stern of the hull, wherein the distance (D) between the central crosswise axis (B) and the one or more inner towline stopper and / or the two outer towline stoppers is equal to or less than the half or 50% of the distance between the stern and the central crosswise axis (B), such as 40%, 30%, 25%, 20%, 15%, 12% of the distance between the stern and the central crosswise axis (B).

[0061] In one embodiment of the present invention, a towing vessel / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising an innermost inner towline stopper and two outermost inner towline stoppers arranged between the two propulsion systems.

[0062] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) and a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising an innermost inner towline stopper and two outermost inner towline stoppers arranged between the two propulsion systems, and wherein the innermost inner towline stopper is arranged on the longitudinal axis (A) of the hull between the winch and the two outermost inner towline stoppers, and wherein the innermost inner towline stopper is arranged as to engage the at least one towline extending from the at least one winch, thereby placing the towing point at the location of the innermost inner towline stopper between the two propulsion systems on the longitudinal axis (A) of the hull and between the winch and the two outermost inner towline stoppers.

[0063] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising an innermost inner towline stopper and two outermost inner towline stoppers, wherein the innermost inner towline stopper and the two outermost inner towline stoppers are arranged between the two propulsion systems, and wherein the innermost inner towline stopper is arranged on the longitudinal axis (A) of the hull between the winch and the two outermost inner towline stoppers, and wherein the two outermost inner towline stoppers are arranged rearwardly from the innermost inner towline stopper, between the innermost inner towline stopper and the stern of the hull.

[0064] In one embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising an innermost inner towline stopper and two outermost inner towline stoppers arranged between the two propulsion systems, wherein the innermost inner towline stopper is arranged on the longitudinal axis (A) of the hull between the winch and the two outermost inner towline stoppers, and wherein the two outermost inner towline stoppers are arranged rearwardly from the innermost inner towline stopper, between the innermost inner towline stopper and the guiding element, and wherein at least one of the two outermost inner towline stoppers is arranged to engage the least one towline extending from the innermost inner towline stopper towards the outer towline stoppers and / or the guiding element, thereby placing the towing point at the location of the outermost inner towline stopper engaging with the at least one towline, such that the towing point is placed between the two propulsion systems and between the innermost inner towline stopper and the guiding element rearwardly from the innermost inner towline stopper.

[0065] In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the two propulsion systems arranged along the central longitudinal axis (A) separated by a distance (D), wherein the hull further comprises a towing staple comprising an innermost inner towline stopper and two outermost inner towline stoppers arranged between the two propulsion systems and wherein the innermost inner towline stopper are arranged between and in relation to the two propulsion systems at a distance D1 rearwardly between the central crosswise axis (B) of the hull and the stern of the hull and wherein the two outermost inner towline stoppers are arranged between and in relation to the two propulsion systems at a distance D2 rearwardly between the central crosswise axis (B) of the hull and the stern of the hull, and wherein both distance D1 and distance D2 between the central crosswise axis (B) and any of the one or more inner towline stopper and / or the two outer towline stoppers is less than the distance between the stern and the central crosswise axis (B), such that the either distance D1 and / or distance D2 is equal to or less than the half or 50% of the distance between the stern and the central crosswise axis (B), such as 40%, 30%, 25%, 20%, 15%, 12% of the distance between the stern and the central crosswise axis (B). In another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising an innermost inner towline stopper and two outermost inner towline stoppers arranged between the two propulsion systems, and wherein the innermost inner towline stopper and the two outermost inner towline stoppers are arranged between the two propulsion systems on and / or in close proximity to the central crosswise axis (B) of the hull.

[0066] In yet another embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising an innermost inner towline stopper and two outermost inner towline stoppers, the three inner towline stoppers arranged between and in relation to the two propulsion systems such that the distance D1 between any of the three inner towline stoppers and the central crosswise axis (B) of the hull is 25% or less of the longitudinal length (L) of the hull, such as 20% or less, such as 15% or less, such as 12% or less or such as 10% or less of less of the longitudinal length (L) of the hull.

[0067] In one embodiment of the present invention a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising outer towline stoppers arranged between the two propulsion systems and a guiding element mounted to the hull by means of the two outer towline stoppers, the guiding element extending between the two outer towline stoppers in a first plane substantially parallel to the deck arranged for allowing the towline to move freely along the periphery of the guiding element between the two outer towline stoppers.

[0068] In one embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising outer towline stoppers arranged between the two propulsion systems and a guiding element mounted to the hull by means of the two outer towline stoppers, the guiding element extending between the two outer towline stoppers in a first plane substantially parallel to the deck arranged for allowing the towline to move freely along the periphery of the guiding element between the two outer towline stoppers hull, the towing staple further comprising at least one tow pin, wherein the at least one tow pin is arranged for being reversibly displaceable between a retracted position and engaging position where the tow pin engages with the guiding element thereby creating a reversible physical obstruction for the movement of the towline along the guiding element. In one embodiment of the present invention a vessel for towing / tugboat is provided comprising a hull along the central longitudinal axis (A) and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising outer towline stoppers arranged between the two propulsion systems and a guiding element mounted to the hull by means of the two outer towline stoppers, the guiding element extending between the two outer towline stoppers in a first plane substantially parallel to the deck arranged for allowing the towline to move freely along the periphery of the guiding element between the two outer towline stoppers, the towing staple further comprising at least one tow pin, mounted to the hull, wherein the at least one tow pin is arranged for being reversibly displaceable between a retracted position and engaging position where the tow pin engages with the guiding element thereby creating a reversible physical obstruction for the movement of the towline along the guiding element, and wherein the tow pin is arranged directly above the rearward propulsion system.

[0069] In one embodiment of the present invention, a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising outer towline stoppers arranged between the two propulsion systems and a guiding element mounted to the hull by means of the two outer towline stoppers, the guiding element extending between the two outer towline stoppers in a first plane substantially parallel to the deck arranged for allowing the towline to move freely along the periphery of the guiding element between the two outer towline stoppers and at least one tow pin mounted to the hull by a tow pin mounting staple, wherein the tow pin mounting staple comprises a upper surface arranged for supporting the towline when one or more tow pins are arranged in engaging position, such that a closed guiding surface is constructed by the one or more tow pin, the surface of the guiding element and the upper surface of the tow pin mounting staple.

[0070] In one embodiment of the present invention, the tow pins are utilized for locking the towline between two tow pins, the surface of the guiding element between the two tow pins and the upper surface of the tow pin mounting staple during direct towing, thereby creating a towing point at the location of the tow pins. In one embodiment of the present invention the towing pins are placed on the central longitudinal axis of the towing vessel / tugboat, directly above the rearward propulsion system, thereby directing the towing forces directly at the location of the rearward propulsion system for better utilization of the propulsion forces and more stability of the towing vessel / tugboat during direct towing procedure.

[0071] In one embodiment of the present invention a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising outer towline stoppers arranged between the two propulsion systems, wherein the outer towline stoppers are arranged as to control and optimize the placement of the towing point during indirect towing procedure.

[0072] In yet one embodiment of the present invention a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising outer towline stoppers arranged between the two propulsion systems, wherein the engagement of one of the outer towline stoppers with the towline during indirect towing, results in the towing point being placed at the placement of the outer towline stopper engaging with the towline, thereby controlling and optimizing the placement of the towing point between the two propulsion systems during the indirect towing, and thereby ensuring that the placement of the towing point is optimal for the stability of the towing vessel / tugboat, while simultaneously constructing a save failure mode by improving the equilibrium position of the towing vessel / tugboat.

[0073] In yet another embodiment of the present invention a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising two outer towline stoppers and one or more inner towline stopper arranged between the two propulsion systems and a guiding element mounted to the hull by means of the two outer towline stoppers, the guiding element extending between the two outer towline stoppers in a first plane substantially parallel to the deck arranged for allowing the towline to move freely along the periphery of the guiding element between the two outer towline stoppers, wherein if and when the towline exits the towing vessel / tugboat at the periphery of the guiding element, without engaging with either of the two outer towline stoppers while engaging with one or more of the inner towline stoppers, the inner towline stopper engaging with the towline constructs the towing point, and thereby the arrangement of the inner towline stoppers controls and optimizes the placement of the towing point in relation to and between the two propulsion systems during the towing procedure.

[0074] In one embodiment of the present invention a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising two outer towline stoppers and one or more inner towline stopper arranged between the two propulsion systems, the towing staple further comprising a guiding element mounted to the hull by means of the two outer towline stoppers, the guiding element extending between the two outer towline stoppers in a first plane substantially parallel to the deck arranged for allowing the towline to move freely along the periphery of the guiding element between the two outer towline stoppers, and wherein if and when the towline exits the towing vessel / tugboat at the periphery of the guiding element, without engaging with either of the two outer towline stoppers while engaging with the innermost inner towline stopper, the towing point is the point of engagement between the innermost inner towline stopper and the towline, and thus the arrangement of the innermost inner towline stopper controls and optimizes the placement of the towing point between the two propulsion systems.

[0075] In one embodiment of the present invention a vessel for towing / tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising two outer towline stoppers arranged between the two propulsion systems and one or more inner towline stopper arranged between the two propulsion systems, wherein the arrangement of the one or more inner towline stopper and / or the two outer towline stoppers between the two propulsion systems ensures that during an indirect towing procedure, the pulling forces applied through the at least one towline on the hull rotates the hull, such that the angle (C) between the central longitudinal axis (A) of the hull and the at least one towline is not 90 degrees.

[0076] In one embodiment of the present invention a vessel for towing / a tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the towing vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising two outer towline stoppers and one or more inner towline stopper arranged between the two propulsion systems, in close proximity to the central crosswise axis of the hull of the towing vessel / tugboat, wherein the arrangement of the outer towline stoppers and the one or more inner towline stopper and thereby the placement of the towing point in relation to and between the two propulsion systems results in a improved equilibrium position, that is the position that the towing vessel / tugboat returns to or seeks during shut down, failure of towline or save failure, that is during disruption of towing procedure. The equilibrium position is the position that the towing vessel / tugboat seeks or wants, and is also the staring position, when the towing vessel / tugboat is running or driving at low speed / engine power. The equilibrium position is the position that the towing vessel / tugboat will return to or align to, during failure, such as snapping of the towline and / or engine failure.

[0077] In one embodiment of the present invention a vessel for towing / a tugboat is provided comprising a hull with longitudinal length (L) along the central longitudinal axis (A) of the vessel / tugboat and two propulsion systems arranged along the central longitudinal axis (A), a forward propulsion system arranged at the forward of the hull and a reward propulsion system arranged at the reward of the hull, the hull further comprising a towing staple comprising outer towline stoppers and one or more inner towline stopper arranged between the two propulsion systems, wherein during different towing procedures one or more towline stopper engages with a towline, and wherein the towline stopper engaging with the towline constructs the towing point, wherein the arrangement of the towline stoppers between the two propulsion system controls and optimizes the placement of the towing point between the forward propulsion system and the reward propulsion system in close proximity to central crosswise axis of the vessel / tugboat. This placement of the towing point in close proximity to the central crosswise axis of the vessel / tugboat, ensures that there is a distance between each of the two propulsion system and the towing point, thereby providing two lever arms from the pivot point of the centrally placed towing point to the point of force, created by the two propulsion systems, thereby creating a torque for considerably increased utilization of the force of the two propulsion systems.

[0078] Definitions:

[0079] The phrases “towing vessel", “tugboat', “vessel for towing” and “a tug are used interchangeably within this application, and refer to a boat or a vessel, that is designed for and applied as an assistance boat which helps in the mooring or berthing operation of a ship by either towing or pushing a vessel towards the port.

[0080] A “towing vessel', “tugboat' or “a tug" is a particular class of boat which helps megaships enter or leave a port. In addition to towing the vessel towards the harbor, tugboats can also be engaged to provide essentials, such as water, air, etc., to a vessel.

[0081] The propulsion system of a “towing vessel', “tugboat' or “a tu j’ is the main reason behind their strength, and together with their solid structural engineering, tugs are small but relatively powerful machines, with tonnage ratio ranging between 2.20-4.50 for large tugs and 4.0-9.5 for harbor tugs. These are incredibly high ratios, especially considering the ratio of cargo ships or vessels varies between 0.35 and 1 .20.

[0082] Since “towing vessel', “tugboat' or “a tucj’ maneuverability is one of its assets, it is important to maintain maneuverability while increasing the strength and power of the propulsion system and even more importantly increasing the utilization of the power of the tugboat by improving the tugboats stability during full power pull and / or high-speed pulling.

[0083] Rearward / rearwards:

[0084] The phrases “reward / s, back, backward / s or rear-end’ as used within this application, is to be understood in the content of this disclosure as being utilized in relation to the towing vessel / tugboat and the towing vessels / tugboats sailing direction, thus referring to the direction towards the stern of the towing vessel / tugboat.

[0085] Forward / forwards:

[0086] The phrases forward / s or front, as used within this application, is to be understood in the content of this disclosure as being utilized in relation to the towing vessel / tugboat and its sailing direction, thus referring to the bow of the towing vessel / tugboat.

[0087] In close proximity to:

[0088] The phrase “in close proximity to" or close to, as used within this application, is to be understood in the content of this disclosure as being closer to one point than another. This can be in a situation where there is a line or distance that can be divided in two, by a midpoint, and then an object or point “in close proximity to" the midpoint, would mean that said object / point is closer to the midpoint than to either endpoint.

[0089] The phrase “towing point’ as used within this application, is to be understood in the content of this disclosure as the location or point on the hull of the towing vessel / tugboat, where, during towing procedure, the towing line applies the forces of the towing procedure on the tugboat. This means that the phrase “towing point” as used within this application refers to the location receiving majority of the towing forces during towing procedure. The towing point may vary between different types of tugboats, and the location of the towing point and thereby the point where the majority of the tugging forces are applied on the tugboat, has a major influence on the performance, characteristics and performance of a towing vessel or tugboat during towing procedure.

[0090] Save failure mode:

[0091] The phrase “save failure mode" as used within this application, is to be understood in the content of this disclosure as a safety feature that allows the captain / crew of the tugboat / towing vessel to react in a save manner to a pending risk of the towing vessel / tugboat girting and capsizing, such that an abrupt halt to the towing procedure will not result in any hazardous events, such as un-stabilizing forces on the towing vessel / tugboat, any sudden movement of the towing vessel / tugboat, snapping or abrupt movement of the towline or other risks for the stability of the towing vessel / tugboat and / or the health of the crew.

[0092] Propulsion system interaction:

[0093] The phrases “propulsion systems interaction" or “thruster-to-thruster interaction" as used within this application, are to be understood in the content of this disclosure, as the possible interaction or interference of the waterflow from one of the two propulsion system on the other propulsion system. As the present invention provides a vessel for towing / a tugboat with a forward propulsion system and a reward propulsion system arranged along the longitudinal direction of the towing vessel / tugboat, there are situations or positions of the towing vessel / tugboat, wherein the flow of the water from one of the propulsion device / system can be directed at the other propulsion device / system, thereby creating an interference that decreases the utilization of the power of the propulsion systems and thereby the efficiency of the towing vessel / tugboat.

[0094] Direct towing:

[0095] The phrase “direct towing” used within this application, is commonly understood within the field, as a method of towing, where the towing vessel / tugboat is attached to the bigger ship by a towline, the tugboat moving forward while utilizing the towline for towing or dragging the bigger ship directly behind and wherein the towline is exiting the towing vessel / tugboat along the central longitudinal axis A of the tugboat.

[0096] Indirect towing:

[0097] The phrase “indirect towincj’ used within this application, is understood within this disclosure as a method of towing, where the towing vessel / tugboat is attached to the bigger ship by a towline, and where due to the circumstances, such as lack of space for manoeuvring the tugboat / towing vessel, the tugboat is towing the bigger ship at an angle, such that the towing line is directly engaging with one of the outer towline stoppers, and the location of the outer towline stopper directly engaging with the towline is the towing point during such towing procedure.

[0098] Semi-direct The phrase “semi-direct towin ’ used within this application, is understood within this disclosure as a method of towing, where the towing vessel / tugboat is attached to the bigger ship by a towline, and where the tugboat is towing the bigger ship at an angle that lies between the angle created during indirect-towing and the direct towing, such that the towing line is not lined up to the central longitudinal axis A of the tugboat as during direct towing, but not exiting the tugboat by interacting directly with one of the outer towline stopper, but exiting the tugboat along or in the periphery of the guiding element between the central longitudinal axis A of the tugboat and the two outer towline stoppers.

[0099] Description of the Drawing

[0100] Various examples are described hereinafter with reference to the figures. Like reference numerals refer to like elements throughout. Like elements will, thus, not be described in detail with respect to the description of each figure. It should also be noted that the figures are only intended to facilitate the description of the examples. They are not intended as an exhaustive description of the claimed invention or as a limitation on the scope of the claimed invention. In addition, an illustrated example need not have all the aspects or advantages shown. An aspect or an advantage described in conjunction with a particular example is not necessarily limited to that example and can be practiced in any other examples even if not so illustrated, or if not so explicitly described.

[0101] Exemplary embodiments of the invention are described in the figures, whereon:

[0102] Fig. 1A illustrates a side view of an embodiment of a tugboat with a towing staple according to the present invention.

[0103] Fig. 1 B illustrates a side view of another embodiment of a tugboat with a towing staple according to the present invention.

[0104] Fig. 2 illustrates a top-down view of an embodiment of a towing staple on a tugboat according to the present invention.

[0105] Fig 3. illustrates a side view of an embodiment of a towing staple on a tugboat according to the present invention.

[0106] Fig. 4 illustrates a front view of an embodiment of a towing staple on a tugboat according to the present invention.

[0107] Fig. 5 illustrates a partly front view, partly side view of an embodiment of a tugboat with a towing staple according to the present invention.

[0108] Fig. 6 illustrates a top view of an embodiment of a tugboat with a towing staple according to the present invention. Fig. 7 illustrates a partly front view, partly side view of an embodiment of a towing staple on a tugboat according to the present invention.

[0109] Fig. 8a illustrates the position of a towing vessel / tugboat, comprising a towing staple according to an embodiment of the present invention during indirect towing procedure.

[0110] Fig. 8b illustrates the rotation achieved by a towing vessel / tugboat, comprising a towing staple according to an embodiment of the present invention during indirect towing procedure.

[0111] Fig. 9 illustrates a top view of an embodiment of a tugboat with a towing staple according to the present invention, demonstrating the length of the tugboat.

[0112] Detailed Description of the Invention

[0113] Exemplary examples will now be described more fully hereinafter with reference to the accompanying drawings. In this regard, the present examples may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the examples are merely described below, by referring to the figures, to explain aspects.

[0114] Throughout the specification, when an element is referred to as being “connected” to another element, the element is “directly connected” to the other element, “electrically connected”, “fluidic connected” or “communicatively connected” to the other element with one or more intervening elements interposed there between.

[0115] The terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting. As used herein, the terms “comprises" "comprising" "includes" and / or "including" when used in this specification specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0116] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this invention pertains. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly defined in the present specification. Fig. 1A and Fig. 1 B demonstrate embodiments of a hull (1) for a vessel for towing / a tugboat, such as a towing vessel / tugboat provided by the present invention. The hull (1) of the towing vessel / tugboat comprises a deck (13), such as a main deck of the towing vessel / tugboat and a towing staple (14) for guiding one or more towing lines (10) (not shown). The deck (13) may be a first deck arranged above a waterline of the hull. There can be one towing line (10) or multiple towing lines (10), the one or more towing line (10) may be towing lines arranged on the hull (1) or / and may be towing lines (10) arranged on a towed vessel. When the one or more towing line (10) is arranged on the hull (1) it may be connected to one or more winch (12) that is mounted to the hull (1). There can be one winch (12) or more than one winch (12), arranged for allowing one or more towing lines (10) to be extended and retracted by being wound up or unwounded from the one or more winch (12).

[0117] The one or more winches (12) are preferably arranged laterally amidships, such as centered on longitudinal axis A of the hull extending from the bow to the stern in the center of the hull (1) (axis A is not shown in Fig. 1 , but demonstrated in Fig 2, 4, 6-9) or in close proximity of the longitudinal axis A, depending on the number of winches (12) and the available space for mounting the one or more winches to the hull (1).

[0118] The hull (1) for a vessel for towing, such as a tugboat further comprises two propulsion systems aligned along the central longitudinal axis A of the hull (1), a forward propulsion system (25A) arranged at the forward of the hull (1) and a reward propulsion system (25B) arranged at the rearward of the hull (1), the two propulsion systems separated by the distance D along the central longitudinal axis A. The two propulsion systems may be any suitable propulsion systems known in the art, such as one or more omni-directional propulsion devices, azimuth thrusters, single-screw or twin-screw fixed propellers, Voith-Schneider propellers or any other suitable propulsion devices.

[0119] The embodiments of the present invention demonstrated in Fig. 1A and 1 B both provide a vessel for towing, such as a tugboat, wherein the hull (1) is provided with at least one keel (26), in order to increase lateral resistance and towline forces of the towing vessel / tugboat in transverse direction under influence of a towing load and to improve course stability of the towing vessel / tugboat.

[0120] The embodiments of the present invention demonstrated in Fig. 1A and 1 B provide a vessel for towing, such as a tugboat, comprising a towing staple (14), wherein the towing staple (14) comprises a support element (17), the support element (17) comprising a forward mounting section (22) and a rearward mounting section (21), the forward mounting section (22) extending forwards towards the bow of the hull (1). The forward mounting section (22) is mounted to the hull (1), by being mounted to the bridge or wheelhouse (23) of the hull (1) as demonstrated in Fig. 1A, or by being arranged as an integrated part of the bridge (23) as demonstrated in Fig. 1 B, or the forward mounting section (22) may be mounted to the hull (1) by any suitable means, such as by specific beams or other mounting means or any mixture of the above mentioned embodiments, such that the forward mounting section (22) is partly attached, partly integrated with the bridge or wheelhouse (23). The rearward mounting section (21) of the support element (17) is mounted to the hull (1) by means of two outer towline stoppers (15A, 15B), the rearward mounting section (21) extending between the two outer towline stoppers (15A, 15B) and the segment of the rearward mounting section (21) that extends between the two outer towline stoppers (15A, 15B) comprising a guiding element (20), the guiding element (20) extending between the two outer towline stoppers (15A, 15B) in a first plane substantially parallel to the deck (13) and wherein the two outer towline stoppers (15A, 15B) and the guiding element (20) together construct a guiding surface (23) constructed for allowing the one or more towline (10) to move freely along the periphery of the guiding element (20) between the two outer towline stoppers (15A, 15B), such that towline is inhibited from upwards movement by the guiding element

[0121] The support element (17) of the towing staple (14) of the embodiments of the present invention demonstrated in Fig. 1A and 1 B further comprises an additional mounting element (18), mounted to the hull (1) between the forward mounting section (22) and the rearward mounting section (21).

[0122] The towing staple (14) of the embodiments of the present invention demonstrated in Fig. 1A and 1 B further comprises one or more inner towline stopper (16) mounted to the hull (1), arranged for receiving one or more towline (10) (not shown in Fig. 1A or 1 B) from the one or more winch (12) and engaging with the one or more towlines (10) such that the pulling forces applied on the towing vessel / tugboat, through the towline, when the towline exits the towing vessel / tugboat anywhere along the periphery of the guiding element, are applied on the one or more inner towline stopper (16), such that the one or more towline stopper (16) defines and thereby controls and optimizes the position of the towing point of the towing vessel / tugboat provided by the present invention, during towing procedure where the towing line (10) exits the hull (1) along the periphery of the guiding element (20). As demonstrated in Fig. 1A and 1 B, the towing staple (14) of the embodiments of the present invention demonstrated comprises more than one inner towline stopper (16).

[0123] The towing staple (14) of the embodiments of the present invention shown in Fig. 1A and 1 B further comprises one or two tow pins (27) mounted to the hull (1), arranged as to be reversibly displaceable between a retracted position and engaging position, such that when the one or two tow pins (27) are in an engaging position, one or more of the tow pins engages with the guiding element (21) of the towing staple (14), thereby creating a reversible physical obstruction for the movement of the towline (10) along the periphery of the guiding element (20). The tow pins (27) of the embodiments shown in Fig. 1 A and 1 B are mounted to the hull directly above the rearward propulsion system (25B), for additional stability of the towing vessel / tugboat during direct towing, that is when the towline (10) is locked by the tow pins (27), whereby the towing point is placed directly above the rearward propulsion system (25B), resulting in more efficiency of the towing vessel / tugboat by improved utilization of the propulsion system during direct towing.

[0124] Fig. 2 illustrates a top-down view of a rear end of a vessel for towing, such as a tugboat, comprising an embodiment of a towing staple (14) according to the present invention. The towing staple (14) is mounted to the deck (13) of the hull (1) and comprises a support element (17), that in the embodiment shown in fig. 2 comprises additional mounting elements (18) mounting the support element to the hull (1), between the rearward mounting section (21) and the forward mounting section (22), where in the embodiment disclosed in Fig. 2, the additional elements (18) are constructed as two pairs of additional elements on each side of the hull (1). It should be noted that the additional mounting elements (18) are not an essential feature of the present invention. The rearward mounting section (21) is mounted to the deck (13) of the hull (1) by means of an outer towline stopper (15A) on one side of the hull (1) and by means of an outer towline stopper (15B) on the other side of the hull (1). The rearward mounting section (21) comprises a guiding element (20) extending between the two outer towline stoppers (15A, 15B), in a first plane substantially parallel to the deck (13), the guiding element (20) constructed for allowing the one or more towline (10) to move freely along the periphery of the guiding element (20) between the two outer towline stoppers (15A, 15B).

[0125] The rearward mounting section (21) of the embodiment of a towing staple (14) according to the present invention extends between the two outer towline stoppers (15A, 15B) in a semi-oval shape, such that the guiding element (20) stretches somewhat along the central longitudinal axis (A) between the outer towline stoppers, but does not follow the curvature of the gunwale (2) as shown in Fig. 2, such that the distance between the guiding element (20) and the gunwale (29) is not constant along the periphery of the guiding element (20).

[0126] The towing staple (14) of the embodiment shown in Fig. 2, further comprises three winches (12) mounted to the hull (1), and three inner towline stoppers (16) mounted to the hull, the winches (12) arranged laterally amidships, that is the winches are arranged centrally on or close to the longitudinal axis A of the hull extending from the bow to the stern along the longitudinal center of the hull (1). It should be noted that the present invention includes any number of winches, such as one, two, three or more winches. The three inner towline stoppers (16A, 16B, 16B’) of the embodiment demonstrated in Fig. 2 are arranged as to construct a triangle, with the innermost inner towline stopper (16A) mounted to the hull between the three winches and the two outermost inner towline stoppers (16B, 16B’), the innermost inner towline stopper (16A) arranged centrally on or very close to the longitudinal axis A of the hull, while the two outermost inner towline stoppers (16B, 16B’) are mounted to the hull (1) rearwards from the three winches and the innermost inner towline stopper (16A), with a longer distance from the central longitudinal axis A than the innermost inner towline stopper (16A) and are arranged symmetrically with the same distance from both the central longitudinal axis A and the innermost towline stopper (16A).

[0127] In the embodiment of the present invention, shown in Fig. 2, the towing line (10) is arranged for being extended and retracted by being wound up or unwounded from the middle winch of Fig 2 and extends from the middle winch towards to the innermost inner towline stopper (16A) and engages with the innermost inner towline stopper (16A) before extending to and engaging with the outer towline stopper (15B), that is the towing staple demonstrated in Fig. 2 is shown during indirect towing procedure, wherein the towline (10) engages directly with the outer towline stopper (15B) and thereby ensures that the towing forces are applied at the location of the outer towline stopper (15B) wherein the location of the outer towline stopper (15B) becomes the towing point during the indirect towing procedure. This arrangement and engagement between the towline (10) and the outer towline stopper (15B), results in the towing point being the placement of the outer towline stopper (15B), the position of the outer towline stopper (15B) being controlled and optimized such that the placement of the towing point during the indirect towing is optimal for the stability of the towing vessel / tugboat and for creating a save failure mode, wherein the placement of the outer towline stopper (15B) engaging with the towing line (10) and thus the location of the towing point of the towing vessel / tugboat during towing procedure, is optimized for enabling the captain / crew of the tugboat / towing vessel to react in a save manner to a pending risk of the towing vessel / tugboat girting and capsizing, such that an abrupt halt to the towing procedure will not result in any hazardous events, such as un-stabilizing forces on the towing vessel / tugboat, any sudden movement of the towing vessel / tugboat, snapping or abrupt movement of the towline or other risks for the stability of the towing vessel / tugboat and / or the health of the crew.

[0128] The towing staple (14) of the embodiment of the present invention shown in Fig. 2 further comprises one or two tow pins (27) mounted to the hull (1) by a tow pin mounting staple (28), the one or two tow pins (27) arranged as to be reversibly displaceable between a retracted position and engaging position, such that when the one or two tow pins (27) are in an engaging position, one or more of the tow pins engages with the guiding element (21) of the towing staple (14), thereby creating a reversible physical obstruction for the movement of the towline (10) along the guiding element (20). In the embodiment illustrated in Fig. 2, the one or more tow pins (27) are placed centrally on the longitudinal axis A of the hull (1).

[0129] Fig. 3 illustrates a side view of an embodiment of a towing staple (14) according to the present invention, on a vessel for towing, such as a tugboat, the towing staple comprising a support element (17) comprising a forward mounting section (2) mounted to the bridge (23) and a rearward mounting section (21), the rearward mounting section (21) comprising a guiding element (20), (the mounting of the rearward mounting section (21) to the hull (1) is not demonstrated in Fig. 3), the support element (17) further mounted to the hull (1) between the forward (22) and the rearward (21) mounting sections by an additional mounting element (18). The towing staple (14) of the embodiment of the present invention shown in Fig. 3 further comprises at least one winch (12) and three inner towline stoppers (16A, 16B, 16B’), arranged and mounted to the hull (1) between the rearward mounting section (21) and the at least one winch (12), wherein the innermost inner towline stopper (16A) is arranged as to be closest to the winch (12) for receiving and engaging one or more towline (10) from the winch (12), and the two outermost inner towline stoppers (16B, 16B’) are arranged as to receive and engage the one or more towline extending from the innermost inner towline stopper (16A). In the embodiment of the present invention shown in Fig. 3, the innermost inner towline stopper (16A) is coupled with one or both of the outermost inner towline stoppers (16B, 16B’) with a coupling (19).

[0130] The towing staple (14) of the embodiment of the present invention shown in Fig. 3 further comprises one or more tow pins (27) mounted to the hull (1) by a tow pin mounting staple (28), the tow pin mounting staple (28) having a upper surface arranged for supporting the towline when one or more tow pins (27) is arranged in engaging position, such that a closed guiding surface is constructed by the one or more tow pin (27), the surface of the guiding element (20) and the upper surface of the tow pin mounting staple (28).

[0131] In one embodiment of the present invention, the towline is locked between two tow pins, the surface of the guiding element (20) between the two tow pins and the upper surface of the tow pin mounting staple during direct towing, thereby creating a towing point at the location of the tow pins. In one embodiment of the present invention the towing pins are placed on the central longitudinal axis of the towing vessel / tugboat, directly above the rearward propulsion system, thereby directing the towing forces directly at the location of the rearward propulsion system for better utilization of the propulsion forces and more stability of the towing vessel / tugboat during direct towing procedure.

[0132] Fig. 4 illustrates a front view of an embodiment of a towing staple (14) according to the present invention, on a vessel for towing, such as a tugboat, the towing staple comprising a support element (17) arranged as to span majority of the width of the deck

[0133] (13), the support element (17) comprising a rearward mounting section (21) comprising a guiding element (20), the rearward mounting section (21) mounted to the hull (1) with two outer towline stoppers (15A, 15B), close to the gunwale (29). The towing staple

[0134] (14) of the embodiment of the present invention shown in Fig. 4 further comprises three inner towline stoppers (16A, 16B, 16B’), the innermost inner towline stopper (16A) arranged on the central longitudinal axis (A) at the center of the hull (1) and coupled to the two outermost inner towline stoppers (16B, 16B’) with a coupling (19), the two outermost inner towline stoppers (16B, 16B’) arranged more rearwardly (closer to the viewpoint of Fig. 4) than the innermost inner towline stopper (16A), the two outermost inner towline stoppers (16B, 16B’) arranged symmetrically, with the same distance from both the innermost inner towline stopper (16A) and the same distance from the central longitudinal axis (A) as to construct a triangle. It should be noted that the couplings (19) demonstrated in Fig. 4 are not an essential feature of the present invention. Fig. 5 illustrates a partly front view, partly side view of a vessel for towing, such as a tugboat, comprising a towing staple (14) according to one embodiment of the present invention. The tugboat illustrated in Fig. 5 comprises a hull (1) comprising a bridge (23), a forward propulsion system (25A) and a rearward propulsion system (25B), the two propulsion systems aligned along the central longitudinal axis (A) of the hull (1) and a keel (26) arranged along the central longitudinal axis (A) of the hull (1) between the two propulsion systems (25A, 25B). The towing staple (14) of the embodiment of the present invention shown in Fig. 5 comprises a support element (17) comprising a forward mounting section (22) and a rearward mounting section (21), the forward mounting section (22) extending forwards from an additional mounting element (18) mounted to the hull (1) and mounted to the bridge (23) of the hull (1) and the rearward mounting section (21) extending rearwards from the additional mounting element (18), the rearward mounting section (21) being arranged to be mounted to the hull by two outer towline stoppers (15A, 15B), the rearward mounting section (21) comprising a guiding element (20) extending between the two outer towline stoppers (15A, 15B) (only one shown in Fig. 5) in a first plane substantially parallel to the deck (13). The towing staple (14) of the embodiment of the present invention shown in Fig. 5 further comprises one or two tow pins (27) mounted to the hull (1), arranged as to be reversibly displaceable between a retracted position and engaging position, such that when the one or two tow pins (27) are in an engaging position, one or more of the tow pins engages with the rearmost part of the guiding element (21) of the towing staple (14), thereby creating a reversible physical obstruction for the movement of the towline (10) along the guiding surface (24). In the embodiment illustrated in Fig. 5, the one or more tow pins (27) are placed centrally on the longitudinal axis A of the hull, or the directly above the reward propulsion system (25B) and directly under the rearmost part of the guiding element (20) of the rearward mounting section (21) of the towing staple (14).

[0135] Fig. 6 illustrates a top view of a vessel for towing, such as a tugboat, comprising a towing staple (14) according to one embodiment of the present invention. The tugboat shown in Fig. 6 comprises a hull (1) comprising a bridge (23), a deck (13), a gunwale (29), a forward propulsion system (25A) and a rearward propulsion system (25B), the two propulsion systems aligned along the central longitudinal axis (A) of the hull (1). The towing staple (14) of the embodiment of the present invention shown in Fig. 6 comprises a support element (17) comprising a forward mounting section (22) and a rearward mounting section (21), the forward mounting section (22) extending forwards from an additional mounting element (18) mounted to the hull (1) towards and around the bridge (23), the forward mounting section (22) mounted to the bridge (23) and the hull (1) and the rearward mounting section (21) extending rearwards from the additional mounting element (18), the rearward mounting section (21) being arranged to be mounted to the hull by two outer towline stoppers (15A, 15B), the rearward mounting section (21) comprising a guiding element (20) extending between the two outer towline stoppers (15A, 15B) in a first plane substantially parallel to the deck (13). The towing staple (14) of the embodiment of the present invention shown in Fig. 6 further comprises one or more winches (12) mounted to the hull (1) centrally on or in close proximity to the central longitudinal axis (A) of the hull (1) rearwardly from the bridge (23), between the bridge (23) and the the stern of the towing vessel / tugboat, the towing staple further comprising three inner towline stoppers (16A, 16B, 16B’) mounted to the hull (1) rearwardly from the one or more winches, between the at least one winch and the stern of the towing vessel / tugboat, the innermost inner towline stopper (16A) arranged on the central longitudinal axis (A) of the hull (1) and the two outermost inner towline stoppers (16B, 16B’) arranged more rearwardly than the innermost inner towline stopper (16A), between the innermost towline stopper (16A) and the stern of the towing vessel / tugboat, the two outermost inner towline stoppers arranged symmetrically with the same distance from both the innermost inner towline stopper (16A) and the central longitudinal axis (A) as to construct a triangle. The rearward mounting section (21) of the embodiment shown in Fig. 6, extends between the two outer towline stoppers (15A, 15B) in a semi-oval shape, such that the guiding element

[0136] (20) stretches somewhat along the central longitudinal axis (A) between the outer towline stoppers, but does not follow the curvature of the gunwale (2) as shown in Fig. 2, such that the distance between the guiding element (20) and the gunwale (29) is not constant along the periphery of the guiding element (20). As demonstrated in Fig. 6, the embodiment of the towing staple provided comprises a rearward mounting section

[0137] (21) with guiding element (20) that extends towards and at least partly over the rearward propulsion system (25B), such that during direct towing, the towing point is directly above rearward propulsion system (25B).

[0138] Fig. 7 illustrates partly front view, partly side view of a vessel for towing, such as a tugboat, comprising a towing staple (14) according to one embodiment of the present invention. The tugboat shown in Fig. 6 comprises a hull (1) comprising a bridge (23), a deck (13), a rearward propulsion system (25B) and a keel (26). The towing staple (14) of the embodiment of the present invention shown in Fig. 7 comprises a support element (17) comprising a forward mounting section (22) and a rearward mounting section (21), the forward mounting section (22) extending forwards from an additional mounting element (18) mounted to the hull (1) towards and around the bridge (23), the forward mounting section (22) mounted to the bridge (23) and the hull (1) and the rearward mounting section (21) extending rearwards from the additional mounting element (18), the rearward mounting section (21) being arranged to be mounted to the hull by two outer towline stoppers (15A, 15B) (only one shown in Fig. 7), the rearward mounting section (21) comprising a guiding element (20) extending between the two outer towline stoppers (15A, 15B) in a first plane substantially parallel to the deck (13). The towing staple (14) of the embodiment of the present invention shown in Fig. 7 further comprises one or more winches (12) mounted to the hull (1) centrally on or in close proximity to the central longitudinal axis (A) of the hull (1) rearwardly from the bridge (23) and three inner towline stoppers (16A, 16B, 16B’) mounted to the hull (1) rearwardly from the one or more winches, the innermost inner towline stopper (16A) arranged on the central longitudinal axis (A) (not shown in Fig. 7) at the center of the hull (1) and the two outermost inner towline stoppers (16B, 16B’) arranged more rearwardly than the innermost inner towline stopper (16A), the two outermost inner towline stoppers arranged symmetrically from both the innermost inner towline stopper (16A) and the central longitudinal axis (A) as to construct a triangle.

[0139] Fig. 8a and 8b illustrate the position and the rotation possible by a towing vessel / tugboat comprising a towing staple according to the present invention, during indirect towing procedure. The towing vessel / tugboat shown in Fig. 8a and 8b comprises two propulsion systems aligned along the central longitudinal axis A of the hull (1), a towing staple (14) mounted to the hull (1) comprising innermost inner towline stopper (16A) engaging and directing towline (10) to an outer towline stopper (15A) engaging and directing the towline (10) from the hull (1) towards a ship to be towed (50), thereby creating a towing point at the outer towline stopper (15A) where the towline exits the towing vessel / tugboat. As demonstrated in Fig. 8a and 8b, the towing vessel / tugboat thereby has an increased rotatability and increased maneuvering abilities, for full utilization of the available space for towing and better utilization of the towing forces of the towing vessel / tugboat, by the possibility of rotating the towing vessel / tugboat as needed during the indirect towing procedure.

[0140] Fig. 9 illustrates a top view of an embodiment of a tugboat with a towing staple according to the present invention, demonstrating the arrangement of different elements of the towing staple along the length of the tugboat. The tugboat of the embodiment shown in Fig. 9 has a specific longitudinal length (L) along the central longitudinal axis (A). As demonstrated in Fig. 9, the central crosswise axis (B) marks the middle point of the longitudinal length (L), dividing the longitudinal length (L) of the hull (1) into two equal halves (50% - L) each spanning 50 percent of the longitudinal length (L) of the hull (1). As further demonstrated in Fig. 9, each of the two equal halves (50% - L) can be further divided into two equal halves (25% - L) each spanning 25 percent of the total longitudinal length (L) of the hull (1), and each of the two equal halves (25% - L) can be further divided into two equal halves (12.5% - L) each spanning

[0141] 12.5 percent of the total longitudinal length (L). In the embodiment demonstrated in Fig. 9, all inner towline stoppers (16) are arranged within the dotted line marking the one-eight or 12.5% (12.5% - L) of the longitudinal length (L) of the hull (1), that is all the inner towline stoppers (16) are arranged within a distance of 12.5% of the longitudinal length (L) from the central crosswise axis (C).

[0142]

Claims

39CLAIMS1. A hull (1) for a vessel for towing, comprising- a deck (13);- a forward propulsion system (25A) and a reward propulsion system (25B), the two propulsion systems aligned along the central longitudinal axis (A) of the hull (1) separated by the distance (D);- at least one winch (12) comprising at least one towline (10); and- a towing staple (14) for guiding the at least one towline (10) wherein the towing staple (14) comprises:- two outer towline stoppers (15A, 15B), mounted to the hull (1);- a support element (17) comprising a forward mounting section (22) mounted to the hull (1) and a rearward mounting section (21) mounted to the hull (1), the rearward mounting section (21) comprising a guiding element (20) mounted to the hull (1) by means of the two outer towline stoppers (15A, 15B), the guiding element (20) extending between the two outer towline stoppers (15A, 15B) in a first plane substantially parallel to the deck (13) arranged for allowing the towline (10) to move freely along the periphery of the guiding element (20) between the two outer towline stoppers (15A, 15B); and- one or more inner towline stopper (16), mounted to the hull (1) arranged laterally amidships, centrally on or in close proximity to the longitudinal axis (A) of the hull (1), the one or more inner towline stopper (16) arranged for engaging with the at least one towline (10) extending from the at least one winch (12) towards the guiding element (20) and / or one of the two outer towline stoppers (15A, 15B); wherein the one or more inner towline stopper (16) is arranged on and / or in close proximity to the central crosswise axis (B) of the hull (1).

2. A hull (1) according to claim 1, wherein the one or more inner towline stopper (16) is arranged closer to the central crosswise axis (B) of the hull (1) than the reward propulsion system (25B).

403. A hull (1) for a vessel for towing according to claim 1 or 2, the hull having a longitudinal length (L), wherein the one or more inner towline stopper (16) is arranged such that the distance (D1) between one or more inner towline stopper (16) and the central crosswise axis (B) of the hull (1) is 25% or less of the longitudinal length (L) of the hull (1).

4. A hull (1) for a vessel for towing according to claim 3, wherein the distance (D1) between one or more inner towline stopper (16) and the central crosswise axis (B) of the hull (1) is 12.5% or less of the longitudinal length (L) of the hull (1).

5. A hull (1) for a vessel for towing according to any of the preceding claims, the hull having a longitudinal length (L), wherein the outer towline stoppers (15A, 15B) are arranged such that the distance (D2) between the outer towline stoppers (15A, 15B) and the central crosswise axis (B) of the hull (1) is 25% or less of the longitudinal length (L) of the hull (1).

6. A hull (1) for a vessel for towing according to any of the preceding claims, the hull (1) comprising an innermost inner towline stopper (16A) and two outermost inner towline stoppers (16B, 16B’) and wherein:- the innermost inner towline stopper (16A) is arranged on the longitudinal axis (A) of the hull (1) closer to the winch (12) than the two outermost inner towline stoppers (16B, 16B’) and is arranged as to engage the at least one towline (10) extending from the at least one winch (12);- the two outermost inner towline stoppers (16B, 16B’) are arranged between the innermost inner towline stopper (16A) and the outer towline stoppers (15A, 15B) and / or the guiding element (20) and are arranged to engage the least one towline (10) extending from the innermost inner towline stopper (16A) towards the outer towline stoppers (15A, 15B) and / or the guiding element (20); wherein the three inner towline stoppers (16A, 16B, 16B’) are all arranged on and / or in close proximity to the central crosswise axis (B) of the hull (1).

7. A hull (1) for a vessel for towing according to claim 6, the hull having a longitudinal length (L), wherein the three inner towline stoppers (16A, 16B, 16B’) are arranged such that the distance (D1) between anyone of the three inner towline41 stoppers (16A, 16B, 16B’) and the central crosswise axis (B) of the hull (1) is 25% or less of the longitudinal length (L) of the hull (1).

8. A hull (1) for a vessel for towing according to claim 7, wherein the distance (D1) between anyone of the three inner towline stoppers (16A, 16B, 16B’) and the central crosswise axis (B) of the hull (1) is 12.5% or less of the longitudinal length (L) of the hull (1).

9. A hull (1) for a vessel for towing according to any of the preceding claims, wherein the towing staple (14) comprises at least one tow pin (27), mounted to the hull (1), the at least one tow pin (27) being reversibly displaceable between a retracted position and engaging position arranged for engaging with the guiding element (20), thereby creating a reversible physical obstruction for the movement of the towline (10) along the guiding element (20).

10. A hull (1) for a vessel for towing according to claim 9, wherein the at least one tow pin (27) is arranged directly above the rearward propulsion system (25B).

11. A method of using for a vessel for towing according to any of claims 1-10 for indirect towing, wherein the arrangement of the one or more inner towline stopper (16) and the two outer towline stoppers (15A, 15B) ensures that during the indirect towing procedure, wherein the towing point of the vessel is the point of engagement between any of the two outer towline stoppers (15A, 15B) and the towline (10).

12. A method of using a vessel for towing according to any claim 11 , wherein the position of the towing point enables a rotation of the hull (1).

13. A method of using for a vessel for towing according to any of claims 1-10, wherein the towline (10) exits the vessel at a point along the periphery of the guiding element (20) and wherein the towing point of the vessel is the point of engagement between one or more of the inner outer towline stoppers (16) and the towline (10).

14. A method of using for a vessel for towing according to any of claims 6-8, wherein the towline (10) exits the vessel at a point along the periphery of the guiding element (20) and wherein the towing point of the vessel is the point ofengagement between the innermost inner towline stopper (16A) and the towline (10).

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