A pile support device for supporting an elongated pile and a method thereof

FIELD OF THE INVENTION

The present invention relates to a pile support device for supporting an elongated pile, in particular a tubular wind turbine monopile, a pile support system using the pile support device and a method thereof.

BACKGROUND AND PRIOR ART

Systems and devices for retaining monopiles for support of wind turbines have been described previously.

Common for many of these prior art solutions is that they involve rigid structures which allow for monopiles of only one single diameter at a time. In order to adapt these systems to a monopile of a different diameter, the interface towards the monopile has to be fully replaced. One such solution is described in WO 2020/011681 Al describing use of height adjustable benches to support the monopiles.

Systems and devices adaptable for retaining monopiles of different diameters have also been described previously. EP 3575199 Al relates to a monopile fastening system for retaining a monopile of a windmill. The fastening system comprises two vertically uprising standards with a flexible element extending therebetween. The distance between the standards and the length of the flexible element may be varied to adapt the system to monopiles of different diameters. Additionally, the flexible element is in one end connected to an arm designed to pivot inwards towards the monopile, thus allowing the flexible element to adapt to the monopile’s shape during support.

EP 3670318 Al also describes a device for supporting a monopile on a vessel. The solution includes rigid support parts which have a rounded U-shape in cross section, and which are received between vertically oriented uprights. The support surfaces of the support parts are formed by saddles which are rotatable around a horizontal axis parallel to the monopile and/or which can be adjusted in height to be able to accommodate monopiles of different diameters.

In CN 202884266 U another solution is described using a bracket structure for supporting a high temperature petroleum pipeline. The bracket structure comprises rails and pivotable parts which enable the bracket structure to be adapted to pipeline deformations caused by temperature changes in the transported fluid. One disadvantage with these known solutions is that they do not allow pile movements without use of other auxiliary equipment such as heavy lift cranes. In addition to an increase in complexity and operation cost, use of such auxiliary equipment may reduce accuracy as well as an increased need of human interventions. The latter may also involve serious health hazards.

It is an aim of the present invention to provide a pile support device, a pile supporting system and a method thereof that solves or at least mitigates one or more of the aforementioned problems related to the use of prior art systems.

It is further an aim of the present invention to provide a solution which is less complex and/or more adaptable for supporting piles, particularly piles configured as pillars for offshore wind turbines,

It is further an aim of the present invention to provide a solution which is adaptable for supporting piles having a wide range of diameters.

It is further an aim of the present invention to provide a solution which is more adaptable for misalignment between a pile support device and a pile, particularly piles configured as pillars for offshore wind turbines.

In at least one exemplary configuration, the aim of the present invention is further to provide a pile support device adapted to support piles having a conical form along at least part of the pile’s longitudinal length.

In at least one exemplary configuration, the aim of the present invention is further to provide a system and a method to displace piles in both vertical and lateral directions relative to a vessel’s deck.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the main claims, while the dependent claims describe other characteristics of the invention.

In a first aspect, the invention concerns a pile support device for supporting an elongated pile oriented parallel to a flat base.

A pile is herein defined as any elongated object such as steel construction beams or monopiles for wind turbines.

The pile support device comprises a first tiltable pile support element onto which the elongated pile may be arranged, a second tiltable pile support element mirroring in at least one tilt orientation the first tiltable pile support element around a mirror plane Mps position centered between the first and second tiltable pile support elements and a stationary structure. During support of the elongated pile, the mirror plane Mps is aligned with a center plane along the longitudinal direction of the pile.

Each of the first and the second tiltable pile support elements comprise a contact pad contacting the elongated pile during support and a displacement arrangement pivotably fixed to the stationary structure. The displacement arrangement is further configured to rotate the respective contact pad at least around a rotational axis relative to the mirror plane Mps, for example at least around a rotational axis parallel to the mirror plane Mps.

Furthermore, the displacement arrangement and the contact pads are mutually configured such that the entire contacting surface of each contact pads remains in direct contact with the surface of the pile during pile support, even when the diameter of the pile varies.

A high degree of horizontal stability of the pile during horizontal support on the contact pads is hence achieved.

Each of the contact pads may be configured to reshape when exposed to the weight of the pile to adapt to a shape deviating from a cylindrical shape such as conical. The reshaping may be achieved by distorting / bending the contact pad with a skew component directed perpendicular to the mirror plane Mps.

The first and second tiltable pile support elements may be attached to a supporting frame for fixation to the flat base.

In one exemplary configuration, each displacement arrangement is fixed at both pad ends of the contact pad relative to the direction of the mirror plane Mps.

In another exemplary configuration, each displacement arrangement comprises a first arm fixed at least indirectly to the contact pad, for example at or near the pad end, a second arm having one end section pivotably fixed to the stationary structure and the other end section pivotably fixed to the first arm and a linear actuator such as a hydraulic actuator and/or an electric linear actuator configured to rotate the second lever arm around a rotational axis parallel to the mirror plane Mps. The first arm is preferably pivotably fixed to the pad end, for example via an additional arm.

The linear actuator may be operated by a control system, either through electrical wiring or through wireless signal communication. The control system may be semiautomatic or fully automatic.

In yet another exemplary configuration, each displacement arrangement comprises two first arms fixed at least indirectly to each pad ends of the contact pad relative to the direction of the mirror plane Mps, two second arms having one end section pivotably fixed to the stationary structure and the other end section to the first arms and two linear actuators such as hydraulic actuators and/or electric linear actuators configured to rotate the two second lever arms around a rotational axis parallel to the mirror plane Mps. As for the exemplary configuration mentioned above, the two first arms may be pivotably fixed to each pad ends, for example via a third arm.

In yet another exemplary configuration, the second arm(s) is/are pivotably fixed to the first arm(s) via one or more spherical roller bearings, thereby allowing tilting of the arms with a rotational axis having a component perpendicular to the mirror plane Mps.

In yet another exemplary configuration, the third arm(s) is/are pivotably fixed to the first arm(s) via one or more spherical roller bearings, thereby allowing tilting of the arms with a rotational axis having a component perpendicular to the mirror plane Mps.

The term ‘spherical roller bearing’ is herein defined as a coupling/joint which allows for multi-axis movement between the coupled parts. The spherical roller bearings may also be further configured to allow axial movements of inserted shafts.

In yet another exemplary configuration, one or both of the contact pads comprises at a plurality of pad units distributed with offset perpendicular to the rotational axis of the tiltable pile support element / contact pad.

In yet another exemplary configuration, one or both of the contact pads comprises a plurality of pairs of pad units distributed with offset, preferably perpendicular to the rotational axis of the tiltable pile support element contact pad. Each of the plurality of pairs may be connected by the above-mentioned additional arm / third arm, for example via one or more spherical roller bearings.

Furthermore, when seen along the direction of the mirror plane Mps, each pad unit may be in the shape of a box comprising at least three walls, wherein the two side walls are preferably oriented perpendicular to the top wall. The pad units may also be in the shape of a four wall box, a five wall box, a T-profile, a U-profile, a L- profile or a rectangular plate. Each pad unit may have a length extending between both pad ends of the contact pad.

In yet another exemplary configuration, each of the contact pads is shapeable to at least partly adapt to a cylindrical shape of the elongated pile upon contact.

In yet another exemplary configuration, each of the contact pads is shapeable to at least partly adapt to a conical shape of the elongated pile upon contact, that is, where the diameter of the pile is varying along the longitudinal direction. In yet another exemplary configuration, each of the contact pads is configured to skew with a skew component directed perpendicular to the mirror plane Mps upon contact with a conical shaped part of the elongated pile, thereby achieving at least partly the desired adaptation of the conical shape.

A conical shape of the pile is herein defined as the part of the pile where the pile diameter along its longitudinal direction varies, for example gradually decreasing from one diameter to another diameter.

In yet another exemplary configuration, the contact pads are configured to distort / skew due to the pressure force enforced by the weight of the elongated pile upon contact.

In yet another exemplary configuration, one or both of the contact pads comprises a plurality of pad units distributed with offset, preferably perpendicular to the rotational axis of the tiltable pile support element. The pad units are configured to distort / skew with a skew component directed perpendicular to the mirror plane Mps upon contact with a conical shaped part of the elongated pile.

In a second aspect, the invention concerns a pile support system for supporting a horizontally oriented pile for an offshore wind turbine such as a monopile.

The pile support system comprises a height adjustable support and a pile support device as described above for the first aspect, wherein the pile support device is arranged on the height adjustable support.

In an exemplary configuration of the second aspect, the pile support device and the height adjustable support is configured such that the pile support device is movable along a longitudinal axis L of the pile during pile support.

In another exemplary configuration of the second aspect, the height adjustable support comprises a guiding track oriented along the longitudinal axis L. Furthermore, the pile support device comprises a recess and/or a protrusion for allowing movement along the guiding tracks.

In another exemplary configuration of the second aspect the pile support system further comprises a second pile support device as described above for the first aspect of the invention, wherein the second pile support device is arranged on the height adjustable support. The pile support system of the exemplary configuration may further comprise a first subsystem comprising a first height adjustable support module and the pile support device configured movable along a longitudinal axis L of the pile during pile support and a second subsystem arranged adjacent to the first subsystem along the longitudinal axis L. The second subsystem comprises a second height adjustable support module and the second pile support device configured movable along the longitudinal axis L during pile support. During use, the pile support system may be arranged such that an external support structure is situated next to the first subsystems with its vertical center plane aligned along the mirror plane Mps of the pile support device described above.

Each of the first and the second subsystems may comprise height adjusting means such as hydraulic actuators and/or electrical linear actuators for adjusting the height of the height adjustable support relative to a base floor during use. Such height adjusting means are fixed between the height adjustable supports and the base floor / deck.

The pile support system may further comprise one or more a pile support system bases onto which the height adjustable supports of the first and second subsystems are connected via the height adjusting means. Preferably, a single pile support base is used for both the first and the second subsystems. However, one system base for each subsystem may also be envisaged.

The pile support system base may be configured such that it is movable sideways along a base floor onto which the system base is supported during use. The direction of the sideways movement is perpendicular to the mirror plane Mps.

The side of the pile support system base facing towards the base floor during use may comprise a recess and/or a protrusion for allowing restricted / guided movement on one or more base floor tracks/rails oriented perpendicular to the mirror plane Mps on or within the base floor. Said protrusions may be wheels configured to move on linear rails. Use of low friction sliding bars may also be envisaged.

In addition, or alternatively, the pile support system may be moved by use of a rack- and-pinion system comprising circular gears (pinions) connected to linear gear (rack) arranged along the base floor. The circular gears, and the corresponding drive motor driving the circular gears, may be a separate unit located at one side of the up-ending tool (i.e. along the aft-bow-direction) opposite the locations of the piles.

In particular during displacement of monopiles for wind turbines, a preferred embodiment is the use of both a wheel / rail system and a rack-and-pinion- system in order to handle the excessive weights with sufficient accuracy and safety.

In a third aspect, the invention concerns a method for arranging an elongated pile onto a plurality of pile support devices, wherein each pile support device is in accordance with the features of the first aspect.

In this third aspect, the pile support devices are fixed to a height adjustable support, wherein a lifting mechanism is configured to adjust the height of the adjustable support relative to a base such as a deck of a vessel. The lifting mechanism may comprise one or more hydraulic cylinders.

Further, the mirror plane Mps of each pile support device is aligned, thereby forming a common mirror plane.

The method comprises the steps of

- arranging the height adjustable support below an elongated pile such that a longitudinal orientation of the elongated pile is vertically aligned, or near vertically aligned, with the common mirror plane of the plurality of pile support devices,

- optionally measuring a first minimum distance between the elongated pile and at least one of the plurality of pile support devices using a distance measurement system,

- raising the height adjustable support towards the elongated pile by operating the lifting mechanism, preferably the minimum distance measured by the distance measurement system,

- for each pile support device, tilting the contact pad of the first pile support element and the contact pad of the second pile support element by operating the respective displacement arrangements until contact, or near contact, is achieved between the contact pads and the elongated pile and

- continue operating the lifting mechanism to increase the contact pressure between the contact pads of the plurality of pile support devices and the elongated pile, for example until the contact pads have gained a desired shape.

The arrangement of the height adjustable support below the elongated pile may be achieved by use of rollers, preferably guided by tracks.

The alignment of the elongated pile with the orientation of the common mirror plane is within a tolerance range set inter alia by the precision of the means of arranging the height adjustable support below the pile and/or the precision of the lifting device and/or the capability of the operator. For example, the tolerance range of the angle between the longitudinal orientation of the elongated pile and the common mirror plane may be ±3°. Furthermore, the tolerance range of any displacement of the elongated pile and the common mirror plane may be less than *4 of the average width of the pile support device perpendicular to the mirror plane Mps.

In an exemplary method, the height adjustable support comprises a first height adjustable support module and a second height adjustable support module, and the lifting mechanism comprises a first lifting mechanism for adjusting the height of the first height adjustable support module relative to the base and a second lifting mechanism for adjusting the height of the second height adjustable support module relative to the base. The second lifting mechanism is operable independently of the first lifting mechanism.

Furthermore, the plurality of pile support devices may be arranged / distributed on the first height adjustable support module and the second height adjustable support module.

The first minimum distance is measured using the distance measurement system between the elongated pile and the at least one of the plurality of pile support devices when arranged on the first height adjustable support module. The first height adjustable support module is thus raised towards the elongated pile a vertical distance corresponding to the first minimum distance by operating the first lifting mechanism.

The exemplary method further includes the following steps:

- measuring a second minimum distance between the elongated pile and at least one of the plurality of pile support devices arranged on the second height adjustable support module using the distance measurement system mentioned above or a separate distance measurement system and

- raising the second height adjustable support module towards the elongated pile a vertical distance corresponding to the second minimum distance by operating the second lifting mechanism.

Note that the height adjustable support may comprise more modules and the distance measurement system may measure more minimum distances, thereby acquiring more information concerning any variations of the pile’s diameter along its longitudinal axis.

In another exemplary method, the distance measurement system includes at least one laser arranged on the pile support device, the lifting mechanism and/or the height adjustable support. The distance measurement system may involve other distance measurement devices such as acoustic and/or optical devices emitting waves with other wavelengths than lasers.

In yet another exemplary method, the plurality of pile support devices and the height adjustable support are configured such that the plurality of pile support devices are movable along a longitudinal axis L of the pile during support, for example along tracks. In yet another exemplary method, the method uses a pile support system as described in the second aspect of the invention.

An alternative method for arranging an elongated pile onto a plurality of pile support devices may be envisaged, wherein each pile support device is in accordance with the features of the first aspect.

In this alternative method, the plurality of pile support devices is fixed to a base having a flat surface, wherein the mirror plane Mps of each pile support device is aligned, forming a common mirror plane. The base may be a height adjustable support as described above for the second and third aspect of the invention.

The method comprises the following steps:

- suspending an elongated pile to a lifting device such that a longitudinal orientation of the elongated pile is parallel or near parallel to the flat surface of the base,

- transporting the elongated pile suspended from the lifting device to a position vertically above the plurality of pile support devices and where the longitudinal orientation of the elongated pile is in alignment or near alignment with the orientation of the common mirror plane,

- lowering the elongated pile towards the plurality of pile support devices by operating the lifting device while measuring, continuously or at time intervals, a minimum distance between at least one of the plurality of pile support devices and the elongated pile using a distance measurement system,

- terminating the lowering of the elongated pile when the minimum distance is within a tolerance range,

- for each pile support device, tilting the contact pad of the first pile support element and the contact pad of the second pile support element by operating the respective displacement arrangements until contact is achieved between the contact pads and the elongated pile and

- releasing the suspension between the lifting device and the elongated pile such that the full weight of the elongated pile is supported by the plurality of pile support devices.

The alignment of the elongated pile with the orientation of the common mirror plane is within a tolerance range set inter alia by the precision of the lifting device and/or the capability of the operator of the lifting device. For example, the tolerance range of the angle between the longitudinal orientation of the elongated pile and the common mirror plane may be ±3°. Furthermore, the tolerance range of any displacement of the elongated pile and the common mirror plane may be less than *4 of the average width of the pile support device perpendicular to the mirror plane MPS.

Between the step of tilting the contact pads and the step of releasing the suspension, the lifting device is preferably further lowering the elongated pile until there are insignificant or no tension in a lifting wire of the lifting device.

The tolerance range may be a minimum distance less than 10 % of the length of the pile support device perpendicular to its mirror plane Mps, more preferably less than 5 %, for example 2 %.

In an exemplary method, the distance measurement system includes one or more lasers arranged on the plurality of pile support devices and/or the lifting device and/or the base.

In another exemplary method, the plurality of pile support devices and the base are configured such that the plurality of pile support devices are movable along a longitudinal axis L of the pile when the pile support devices are supporting the full weight of the pile.

In another exemplary method, the method uses a pile support system as described in the second aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings depict alternatives of the present invention and are appended to facilitate the understanding of the invention. However, the features disclosed in the drawings are for illustrative purposes only and shall not be interpreted in a limiting sense.

Figure 1 illustrates a cross sectional aft-to-bow view of an installation vessel, wherein a pair of pile support devices in accordance with the invention are attached on a height adjustable table arranged on the deck of the vessel.

Figure 2 illustrates a more detailed view of the vessel deck, wherein a pile is supported by two pile support devices arranged on a height adjustable table.

Figure 3 illustrates a first embodiment of a pile support device in accordance with the invention from a front view perspective, where the pile support device is shown in a fully open position.

Figure 4 illustrates the first embodiment of the pile support device in a contact configuration, in which the pile support device is shown to support two different piles of two different diameters. Figure 5 illustrates the first embodiment of the pile support device in a contact configuration, in which the pile support device is shown to support two different piles of two different diameters, and wherein one of the piles is of a conical shape.

Figure 6 illustrates from a side view perspective a pile of varying diameters being supported by two pile support devices according to the invention, and wherein the pile support devices are attached to a height adjustable table.

Figure 7 illustrates from a perspective view a second embodiment of a pile support device in accordance with the invention, wherein the pile support device is in its fully open position.

Figure 8 illustrates form a perspective view the second embodiment of the pile support device in a contact configuration, in which the pile support device is supporting a pile.

Figure 9 illustrates from a bird perspective the second embodiment of the pile support device in a contact configuration, but where the pile is omitted to show the details of the pile support device.

Figure 10 illustrates two different perspectives of the pile support device according to the second embodiment, where figure 10A shows the pile support device in a contact configuration with the presence of a pile and where figure 10B shows the pile support device in a contact configuration without the presence of a pile

Figure 11 illustrates in detail an example of a contact pad in accordance with the invention.

Figure 12 illustrates from a side view perspective a method of arranging a pile onto a plurality of pile support devices according to the invention, where figure 12A shows the pile support devices in a fully open position below the pile, figure 12B shows the pile support devices in a contact configuration while partly enveloping the pile and figure 12C shows the pile support devices in the contact configuration while fully supporting the pile.

DETAILED DESCRIPTION OF THE INVENTION

In the following, embodiments of the invention will be discussed in more detail with reference to the appended drawings. It should be understood, however, that the drawings are not intended to limit the invention to the subject matter depicted in the drawings.

Figure 1 shows a cross sectional view along the aft-to-bow direction of a pile support system 100 arranged on a deck 401 of a transport vessel 400. As illustrated, the principal direction of the pile support system 100 is transverse of the vessel’s deck 401, i.e. perpendicular to the aft-to-bow. The vessel 400 may be designed to transport a plurality of horizontal monopiles 200 for offshore wind turbines, all oriented in said direction.

The pile support system 100 shown in figure 1 includes a first subsystem 100a and a second subsystem 100b onto which an inventive first pile support device 10 and an inventive second pile support device 10’ are fixed respectively. Each pile support device 10,10’, hereinafter called diameter adaptive cradle (DAC), may be configured to support monopiles having different diameters and/or conical shapes.

The pile support system 100 will be described further with respect to figure 2 and embodiments and details of the DAC 10,10’ will be described with respect to figures 3 through 11.

Figure 1 also shows a pile up-ending tool 500 arranged at one of the deck boundaries. The pile up-ending tool 500 is pivotable with a rotational axis along the aft-to-bow direction of the vessel 400. The pile up-ending tool 500 comprises a pivot arm 504, an upper support 501 pivotably connected to one upper end of the pivot arm 504 for providing support in a radial direction of the pile 200, an end support 503 connected to an opposite, lower end of the pivot arm 504 for supporting at least part of the pile’s weight when in vertical orientation and a pivotable pile gripper 502 arranged between the upper support 501 and the end support 503, configured to releasably grip the pile’s radial circumference in order to ensure horizontal stability. The pivoting of the pile up-ending tool 500 is ensured by a pivoting mechanism 505 fixed to the deck boundary and pivotably coupled to the pivot arm 504.

In figure 1 a monopile 200 has been rotated by use of the pile up-ending tool 500 from a horizontal orientation on the pile support system 100 to a vertical orientation relative to the vessel’s deck 401.

The up-ending of the monopile 200, when arranged in the pile up-ending tool 500, may be achieved by a lifting device such as a crane fixed with a crane wire to an upper end of the pile 200.

Additional control of the up-ending movement may be ensured by an upending winch 700 installed on the deck 401 at the deck boundary opposite of the pile upending tool 500. A winch cable 701 is connected to the upper end of the monopile 200 allowing continuous adjustment of a tension force towards the deck 401 to avoid uncontrolled rotation away from the vessel 400 during the up-ending.

One specific purpose of this invention is to provide a DAC 10,10’ and a pile support system 100 which can accommodate monopiles 200 of different diameters and shapes, while also allowing controlled displacement of the horizontal monopile 200 from a parking position on the pile support system 100 to a position within the pile up-ending tool 500, thereby enabling the up-ending movement of the monopile 200 from horizontal to vertical to commence.

In figure 2, an inventive pile support system 100 is shown in more detail. The pile support system 100 is placed on the deck 401 of the vessel 400. The pile support system 100 includes a height adjustable first table 100a and a height adjustable second table 100b arranged adjacent to the first table 100a along the longitudinal axis L of the monopile 200. Each of the tables 100a, 100b comprise a table plate 101a, 101b onto which one or more inventive DACs 10,10’ are attached to support the monopile 200. Guiding tracks 106 allow the DACs 10,10’ to move along the longitudinal axis L on each of the table plates 101a, 101b. The upper support 501 and the pile gripper 502 of the pile up-ending tool 500 are also shown in figure 2.

After support of the monopile 200 onto the DACs 10,10’, the pile support system 100 may move the monopile 200 along the longitudinal axis L to the up-ending position within the pile up-ending tool 500 as shown in figure 1, thus enabling the up-ending movement to commence. Such horizontal movement of the monopile 200 is achieved by incrementally moving the monopile 200 synchronically on the DACs 10,10’ along the guiding tracks 106. When the DACs 10,10’ are positioned with a part of the monopile 200 directly above the upper support 501, the DACs 10,10’ may be repositioned one by one to allow the monopile 200 to be moved another increment. This is achieved by first lowering the second table plate 101b so that the second DAC 10’ is no longer in contact with the monopile 200 but resting on the upper support 501 and the first DAC 10. The second DAC 10’ is then moved towards its opposite end along the longitudinal axis L and raised so that the DAC 10’ again engages the monopile 200. The same procedure is repeated for the first table plate 101a and the first DAC 10.

Yet another DAC 10 may form part of the upper support 501 providing direct support of the monopile 200, i.e. arranged / situated within the concave section of the upper support 501 shown in figure 2.

Figure 2 also illustrates additional monopiles supported horizontally on the deck 401 by parking cradles 300. The pile support system 100 may move on rails 107 in the aft-to-bow direction of the vessel 400, perpendicular to the longitudinal axis L, to pick up the monopiles 200 from the parking cradles 300 and feed them into the pile up-ending tool 500 as explained above.

An example of a DAC 10 according to a first embodiment of the invention is shown in figure 3 in a fully open position. The DAC 10 is made up of a first and a second DAC element 10a, 10b symmetrically arranged across an imaginary mirror plane Mps. In this particular embodiment, each DAC element 10a, 10b comprises a contact pad 11 set up by four contact pad units; a first contact pad unit 1 lal,l Ibl, a second contact pad unit I la2,l lb2, a third contact pad unit I la3,l lb3 and a fourth contact pad unit I la4,l lb4. Each contact pad unit 1 lal-4,1 lbl-4 has a three wall box shape where an upper side of the box provides the interface between the DAC 10 and a monopile 200 to be supported.

The first contact pad unit 1 lal,l Ibl and the second contact pad unit I la2,l lb2 of each DAC element 10a, 10b are pivotally fixed to opposite ends of a first contact pad rocker arm (additional arm / third arm) 26al,26bl through a first pivot point 21. Likewise, the third contact pad unit I la3,llb3 and the fourth contact pad unit I la4,l lb4 are pivotally fixed to opposite ends of a second contact pad rocker arm 26a2, 26b2 through another first pivot point 21.

The first pivot points 21 may be provided with a spherical roller bearing to allow for pivotal movements of the contact pad units 1 lal-2,1 la3-4,l lbl-2,1 lb3-4 relative to the contact pad rocker arms 26al -2,26b 1-2 which is not restricted to a rotational axis parallel to Mps.

The first contact pad rocker arm 26a 1, 26b 1 and the second contact pad rocker arm 26a2,26b2 of each DAC element 10a, 10b may further be pivotally fixed to opposite ends of an intermediate rocker arm (first arm) 23 a, 23b through a second pivot point 22. The second pivot point 22 may, like the first pivot points 21, be provided with a spherical roller bearing to allow for pivotal movement of the contact pad rocker arms 26al-2,26bl.2 relative to the intermediate rocker arm 23a, 23b which is not restricted to a rotational axis parallel to Mps.

Still with reference to figure 3, a pivot arm (second arm) 24a, 24b is at one end section pivotally connected to the mid- section of the intermediate rocker arm 23a, 23b through a third pivot point 27. The third pivot point 27 may, like the first pivot points 21 and the second pivot points 22, be provided with a spherical roller bearing to allow for pivotal movements of the intermediate rocker arm 23 a, 23b relative to the pivot arm 24a, 24b which is not restricted to a rotational axis parallel to Mps. The pivot arm 24a, 24b is at another end section pivotally connected to a first stationary structure 30a, 30b, thereby allowing the pivot arm 24a, 24b to rotate about an axis parallel to the mirror plane Mps. The first stationary structure 30a, 30b may be rigidly attached to a base floor, such as a deck 401 of a vessel 400 or a height adjustable support 101 as illustrated in figs. 1, 2, 6 and 12. Also the end section connected to the first stationary structure may include a spherical roller bearing to allow for pivotal movements beyond an axis parallel to the mirror plane Mps.

A linear actuator 25a, 25b is pivotally connected to the pivot arm 24a, 24b at one end and pivotally connected to a second stationary structure 3 la, 3 lb at the opposite end. The second stationary structure 3 la, 3 lb may like the first stationary structure 30a, 30b be rigidly attached to the base floor. The function of the linear actuators 25a, 25b is to facilitate rotation of the pivot arm 24a, 24b about the pivot connection with the first stationary structure 30a, 30b. The linear actuator may be any type of linear actuator suitable for this purpose, such as a hydraulically driven cylinder, an electric linear actuator or a combination thereof. Several linear actuators 25a, 25b arranged in parallel along the base floor to increase strength / safety may also be envisaged.

The linear actuators 25a, 25b may be operated by a control system, either through electrical wiring or through wireless signal communication. The control system may be semi-automatic or fully automatic, manual or a combination thereof.

Note that all components described above are in the first embodiment of fig. 1 also present at the other side of the contact pad units 1 lal-4,1 lbl-4 relative to the mirror plane Mps.

However, embodiments having only one set of the above-described components may also be envisaged. In such an embodiment, the components should be arranged along a center plane of the contact pads 11 perpendicular to the mirror plane Mps.

Each DAC element 10a, 10b preferably includes a number of blocking means (not shown) to prevent the contact pads from rotating away from the monopile 200, at least above a predetermined tolerance angle. The blocking means may be in the form of pins / stoppers and may be arranged between the contact pads 11 and the contact pad rocker arms 26al-2,26bl-2. The blocking means thus allow the contact pads 11 to rotate with a limited degree of freedom away from the monopile 200. The degree of freedom may be up to 15 degrees, or up to 10 degrees, for example 7 degrees.

Figure 4 illustrates the first embodiment DAC 10 of figure 3 while supporting two monopiles 200’, 200” of two different diameters R1,R2. The DAC 10 is in figure 4 in a contact configuration in which the contact pads 11 a, 11b engages the monopile 200 by activation of the linear actuators 25a, 25b. The left-hand side of the dotted line illustrates the DAC 10 while supporting a monopile 200’ of a radius R1 and the right-hand side of the dotted line illustrates the DAC 10 while supporting a monopile 200” of a smaller radius R2. To compensate for the smaller radius R2, the linear actuator 25b is extended further than the linear actuator 25a.

It is emphasized that the contact surfaces of the contact pads I la, 11b fit tightly around the monopiles 200’, 200” due to the multi -joint design provided by pivot points 21,22,27 allowing the contact pads 11 a, 11b to adapt to the shape of the cylindrical monopiles 200’, 200” when pushed into contact by the linear actuators 25a, 25b. The DAC 10 of the first embodiment is configured to support monopiles 200 with diameters of at least 4 meters. Typically, the pile diameter range is between 6 - 11 meters, for example 8 meters.

As for figure 4, figure 5A illustrates the DAC 10 while supporting two different monopiles 200’, 200” of two different diameters R1,R2. However, the left-hand side of the dotted line in figure 5 illustrates the DAC 10 while supporting a part of a monopile 200’ having a conical shape. Due to the pressure exerted by the part of the monopile 200’ the first DAC element 10a is re- shaped by the conical form upon contact to maintain direct contact, thereby ensuring an even distribution of contact pressure across the surface area of the contact pad I la.

The hydraulic cylinder 25a at one side of the contact pad I la is extended a certain length to match a large diameter area of the conical shape while the hydraulic cylinder 25a at the opposite side of the contact pad I la relative to the mirror plane Mps (not shown in figure 5) is extended a greater length to match the smaller diameter area of the conical shape.

The twisting of the first DAC element 10a to accommodate the conical shape is achieved due to the spherical roller bearings provided at pivot points 21,22,27.

In order to further ensure full (or near full) contact with the monopile 200’, each contact pad unit l lal-4 of the contact pad I la may be allowed to distort / skew due to the pressure force enforced by the weight of the monopile 200’ upon contact. As shown in figure 5B, the contact pad units l lal-4 distort with a skew component directed perpendicular to the mirror plane Mps when contacting the conically shaped part of the pile 200’. A specific design of a contact pad unit 1 lai allowing such distortion will be explained in further detail with reference to figure 11.

To increase the integrity and stability of the DAC elements 10a, 10b it is considered advantageous to arrange shafts (not shown) that interconnects the intermediate rocker arms 23a, b and/or the contact pad rocker arms 26al-2,26bl-2 on each side of the DAC elements 10a, 10b beneath the contact pad I la, 11b. Furthermore, when arranging such shafts within spherical roller bearings allowing incremental slide in axial direction, a compensation of increased distances between the rocker arms 23a,b,26al-2,26bl-2 during distortion / bending is achieved, thereby enabling adaption to conical pile sections.

The intermediate rocker arms 23a, 23b on each side of the DAC element 10a, 10b may also be reinforced with one or more additional transverse profiles (not shown) extending between the rocker arms 23a, 23b beneath the contact pads I la, 11b. The transverse profiles may hence provide further stability of the DAC elements 10a, 10b while maintaining the required distance between the intermediate rocker arms 23a, 23b on each side during support of the monopile 200’. The DAC 10 may be designed to adapt to a conical angle of at least 2 degrees, more preferably to a conical angle of at least 4 degrees, for example 5 degrees.

Figure 6 shows a side view of a monopile 200 supported by a first DAC 10 supporting a cylindrical part of the monopole 200 and a second DAC 10’ supporting a conical part of the monopile 200.

The DACs 10,10’ are attached to respective support plates 101a, 101b where each support plate 101a, 101b may be placed on the deck 401 of a transport vessel 400. Figure 6 shows how the two DACs 10,10’ enable stable support of elongated piles despite varying diameters and shapes along the longitudinal length L. See further details below.

As described above, the hydraulic cylinder or electric actuator 25a at the side of the DAC 10’ contacting the conical part with the smaller diameter is extended more than the hydraulic cylinder or electric actuator 25a contacting the conical part with the larger diameter, thereby allowing the contact pad 11 a, 11b of the DAC elements 10a, 10b to accommodate the conical shape. The twisting of the DAC 10 is enabled due to the spherical roller bearings in the multiple pivot points 21,22,27.

The DACs 10,10’ may be configured to support monopiles of a weight of at least 500 tons. Typically, the monopile weights range between 700 and 3600 tons, for example 2400 tons. Furthermore, the pile support system 100 may be configured to support monopiles of a length of at least 50 meters. Typically, the monopile lengths range between 70 and 120 meters, for example 100 meters.

Figure 7 illustrates a second embodiment of the inventive DAC 10 shown in a fully open position.

An important difference of this second embodiment DAC 10 compared to the first embodiment DAC 10 is the presence of more robust displacement arrangements 20a, 20b, i.e. the movable components causing pivoting and/or displacement of the respective contact pads I la, 11b. The displacement arrangement 20a, 20b involves a more compact fit between the contact pad rocker arms 26al,26a2, 26bl,26b2 and the intermediate rocker arms 23a, 23b. The pivot arms 24a, 24b are also more sturdy/massive than for the first embodiment. Moreover, the pivot arms 24a, 24b are in the second embodiment pivotally connected to a common stationary structure 30 fixed to (or forming an integral part of) a base floor 40.

Figure 8 illustrates the second embodiment DAC 10 in a contact configuration while supporting a monopile 200. The linear actuators 25a, 25b on both sides of the contact pads I la, 11b in respect of the mirror plane Mps have been extended to match the particular diameter of the monopile 200. And as described above for the first embodiment, the multi-joint design enables the DAC 10 to adapt to the shape of the monopile 200 upon contact.

Figure 9 shows the DAC 10 in a contact configuration from another angle, but where the monopile 200 has been omitted to better illustrate the adapted shape.

Figures 10A and 10B shows the second embodiment DAC 10 from two different perspective views, in which the DAC is shaped to accommodate a conical section 200”’ of a monopile 200. Figure 10A illustrates the DAC 10 supporting the conical section 200’ ” and figure 10B illustrates the same DAC 10 in which the monopile 200 has been omitted. As can be seen from the figures, the linear actuators 25a, 25b in the smaller diameter part of the conical section 200’” are extended further than the linear actuators 25a, 25b in the larger diameter part of the conical section 200’” so that one side of the DAC 10 is higher than the other relative to the base floor 40, thereby allowing the contact pads I la, 11b to adapt to the conical shape upon contact.

Figure 11 illustrates in detail a single contact pad unit 1 lai forming part of the contact pad I la of the DAC element 10a. The contact pad unit 1 lai has form of a hollow box or a three wall box comprising a contact plate 110, two side walls 111, two transverse sidewalls 112, a T-profile 113 extending between the transverse sidewalls 112, a rod 115 fixing the T-profile 113 to the contact plate 110 and two couplers 114 fixed on the sidewalls 112 opposite of the fixation to the T-profile 113. The couplers 114 may be fixed to one of the contact pad rocker arms 26al,26a2 described above and may include spherical roller bearings.

The contact plate 110 forms the interface between the DAC 10 and the monopile 200 to be supported and has a substantially rectangular surface area. As shown in figure 11, the contact plate 110 may have a slightly concave curvature to enhance the contact area towards a cylindrically shaped monopile 200. Alternatively, or in addition, the contact pad unit 1 lai may be configured such that pressure from the monopile 200 creates such concave curvature.

The surface of the contact plate 110 facing towards the monopile 200 is preferably made of a material that provides a high degree of friction between the monopile 200 and the contact pad I la.

Examples of such high friction materials are synthetic materials such as different types of rubber. In addition to high friction, the material should also be able to handle the weight of the monopile 200.

Alternatively, or in addition, the surface of the contact plate 110 may be designed with a plurality of ribs or other friction creating structures. Due to wear and tear, the friction surface may further be replaceable, thereby avoiding, or at least reducing, the necessity of replacing the entire contact pad I la, 11b or the entire DAC element 10a, 10b.

Preferably, the friction provided by the plurality of contact plates 110 forming the interface towards the monopile 200 is sufficient to keep the monopile 200 fastened within the plurality of DACs 10,10’ of a pile support system 100 without the use of additional fastening means such as straps. This is particularly important when the vessel 400, onto which the pile support system 100 is attached, experiences significant pitch, roll or heave motions.

The longitudinal side walls 111 may further be provided with apertures / slots 111’ into which protrusions 112’ of the transverse side walls 112 may be inserted, thereby allowing the contact pad 11 to twist and distort upon contact with a conical section 200’” of a monopile 200.

The T-profile 113 fixed between the transverse side walls 112 is further reinforcing the contact pad unit Hal, thus increasing the contact pad unit’s rigidity during distortion.

Figures 12A, 12B and 12C illustrates a method for arranging a monopile 200 onto a pair of DACs 10,10’ of a pile support system 100. The number of DACs may in other instances be more than two. The monopile 200 is shown to be supported by a pair of parking cradles 300 attached to the deck 401 of a vessel 400. As explained in relation to figure 2, the pile support system 100 may move perpendicular to the longitudinal axis L of the monopile 200 using rails 107 in order to pick up the monopiles 200 from the parking cradles 300 and feed them into the pile up-ending tool 500.

The pile support system 100 is further provided with a laser system 800. The laser system 800 includes a first laser system 800a comprising a first laser sensor 801a and a second laser sensor 802a attached to the first table plate 101a, and a second laser system 800b comprising a first laser sensor 801b and a second laser sensor 802b attached to the second table plate 101b. The laser sensors 801a, 802a, 801b, 802b, however, may also be placed on other parts, for example on the deck beneath the table plates 101a, 101b and/or directly onto the DACs 10,10’. Although the first and second laser systems 800a, 800b are shown to comprise two laser sensors, the number of laser sensors may in other instances be more than two or less than two.

The first and second laser systems 800a, 800b are configured to measure the height difference between its respective table plate 101a, 101b (and hence also its respective DAC 10,10’) and the monopile 200. This enables the control system to accurately position the DACs 10,10’ in a desired vertical position relative to the monopile 200 by use of the height adjustable tables 100a, 100b, for example upon direct contact.

The laser systems 800a, 800b may also register the shape (e.g. conical, cylindrical) and size (e.g. radius and circumference) of the monopile 200 in a position vertically above the DACs 10,10’. This further enables the control system to determine and operate the DACs 10,10’ to exact position of contact. The linear actuators 25a, 25b may thus be extended to accommodate the shape and size of the monopile 200 above each of the respective DACs 10,10’.

Instead of a system involving lasers, other distance measurement systems suitable for this purpose may be used in order to achieve the above measurement data. Such distance measurement systems may comprise sensors/transmitters transmitting waves of different wavelengths than lasers, for example ultrasonic sensors or radar sensors. Acoustic sensors/transmitters or ultrasonic sensors/transmitters may also be envisaged.

The figures 12A-12C illustrates the method of arranging the monopile 200 onto the pile support system 100 step by step. A first step, illustrated in figure 12A, involves positioning the pile support system 100, with the DACs 10,10’ in a fully open position (i.e. retracted linear actuators 25a, 25b) below the monopile 200 such that the longitudinal axis L of the monopile 200 aligns with a common mirror plane formed by the mirror planes Mps of each DAC 10,10’.

Again with reference to figure 6, the pile support system 100 may comprise two height adjustable tables 100a, 100b, each comprising a support plate 101a, 101b and first and second table linear actuators 102a, 102b configured to raise and lower the support plate 101a, 101b relative to a base (typically the deck 401 of the vessel 400). The two DACs 10,10’ are fixed to the respective support plates 101a, 101b as illustrated.

In a second step, illustrated in figure 12B, the linear actuators 102a, 102b are extended, such that the DACs 10,10’ may be raised to a position upon contact or within immediate vicinity of the monopile 200. Furthermore, the linear actuators 25a, 25b are activated to bring the DACs 10,10’ into the contact configuration, such as to partly envelope the circumference of the monopile 200. The linear actuators 25a, 25b of each of the DACs 10,10’ are hence extended to accommodate the shape and size of the monopile 200 in the position directly above the respective DAC 10,10’.

In a third step, illustrated in figure 12C, the desired full contact between the DACs 10,10’ and the monopile 200 is achieved by raising the table plates 101a, 101b further, such that the full weight of the monopile 200 is carried by the pile support system 100. As illustrated in figure 12C, the monopile 200 is now completely lifted off from the parking cradles 300 and may thus be moved on the pile support system 100 along the rails 107 to a position where it may be fed into the pile up-ending tool 500.

As explained in relation to figures 4 and 5 the contact pads 11 a, 11b and the contact pad units 1 lal-4,1 lbl-4 are manufactured and configured to reshape to create an intimate contact with the pile surface when exposed to the pressure exerted by the monopile 200. It is emphasized that the desired tight fit of the contact surfaces of the contact pads I la, 11b around the monopile 200 may be achieved due to the multi-joint design provided by pivot points 21,22,27, thereby allowing the contact pads 11 a, 11b to adapt to the shape of the cylindrical monopile 200 when pushed into contact by the table linear actuators 102a, 102b. Further, by designing the contact pad units reshapable as shown in figure 11, additional increase in the contact surface may be achieved.

In the preceding description, various aspects of the pile support device, the pile support system and the method for supporting a pile onto the pile support device and system by use of a distance measurement system have been described with reference to the illustrative embodiment. For purposes of explanation, specific numbers, systems and configurations were set forth in order to provide a thorough understanding of the inventive system and its workings. However, this description is not intended to be construed in a limiting sense. Various modifications and variations of the illustrative embodiment, as well as other embodiments of the system, which are apparent to persons skilled in the art to which the disclosed subject matter pertains, are deemed to lie within the scope of the present invention.

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