NL2022173B1

NL2022173B1 - Piling frame with cut-out

Info

Publication number: NL2022173B1
Application number: NL2022173A
Authority: NL
Inventors: Peeters Lukas
Original assignee: Jumbo Maritime B V
Priority date: 2018-12-11
Filing date: 2018-12-11
Publication date: 2020-07-02
Also published as: WO2020122712A1

Abstract

The invention relates to a piling frame (1) for being lifted by a crane (2) of a vessel (3), characterized by the piling frame, when being lifted by the crane, comprising a horizontal circumference zone (4) with a cut-out (5), wherein the cut-out is configured for at least partially receiving a vertical crane mast (6) of the crane. The invention also relates to a vessel comprising such a piling frame, as well as a method for installing piles in a water body using such a piling frame or vessel.

Description

Title: Piling frame with cut-out Description

FIELD OF THE INVENTION The present invention relates to a piling frame for being lifted by a crane of a vessel, a vessel with one or more cranes for lifting such a piling frame, as well as a method for installing piles in a water body using such a piling frame and such a vessel.

BACKGROUND OF THE INVENTION Piling frames are also known as piling templates, in particular subsea piling templates. Piling frames are primarily used for installing piles on or in a seabed of a sea or ocean to form a foundation for a further subsea structure, such as an offshore platform or a wind turbine support structure. Such piling frames usually comprise pile sleeves for guiding the piles into the seabed under the proper angle during the pile driving process. Piling frames often have a triangular or square shape with the pile sleeves being arranged in the corners of the triangle.

A problem with the known piling frames is that they are getting larger and larger in order to form foundations for increasingly large subsea structures on the seabed. This in turn also requires the vessel installing the piles to become larger and larger to be able to accommodate the piling frame. Oftentimes, even when a vessel is actually large enough to store the piling frame onboard, problems may occur when trying to lift the piling frame in between onboard cranes towards the water body (also known as “overboarding”). Or, when a vessel is actually large enough, problems may occur with regards to the capacity of the crane, since the capacity of the crane is restricted by the outreach of the crane: the larger the outreach, the smaller the lift capacity. Operation of large vessels, i.e. vessels with larger cranes, is furthermore highly uneconomical primarily due to the size of such vessels: the larger the vessel, the more expensive exploitation of the vessel. Preferably, the vessel to be used during installation of the piles is thus as small as possible. However, this could again lead tothe vessel not having sufficient size to accommodate and overboard large piling frames. Another problem with the known piling frames and installation methods is that the rate of pile installation in the seabed is relatively low due to the same vessel being used for installing the piles with the piling frame, as well as the subsequent installation of the further subsea structure. The installation of piles thus has to be interrupted frequently for installing the further subsea structure on the created pile foundation. Yet another problem of the present piling frames, as well as the vessels and methods used for installation is that the piles require a lot of onboard storage space. Thus, when a single vessel is used, it is difficult to store the required amount of piles onboard along with the piling frame and further subsea structure.

OBJECT OF THE INVENTION An object of the invention is therefore to provide a piling frame which can be stored and used onboard a relatively small vessel, wherein problems when lifting the piling frame in between onboard cranes (or, for that matter, any other fixed obstruction, such as crew accommodation) towards the water body or problems with the lifting capacity and/or outreach of the cranes are prevented or at least minimized. Another object of the invention is to provide a method for installing piles in a water body with such a piling frame, wherein the pile installation rate is increased. Yet another object of the invention is to provide an installation method or vessel, wherein a relatively larger load of piles can be stored onboard the vessel installing the piles.

DESCRIPTION OF THE INVENTION Hereto, the piling frame according to the invention is characterized by the piling frame, when being lifted by the crane, comprising a horizontal circumference zone with a cut-out, wherein the cut-out is configured for at least partially receiving a vertical crane mast of the crane. Due to the provision of such a cut-out problems when lifting the piling frame in between onboard cranes towards the water body are minimized, due to thecut-out effectively reducing the distance between the vertical crane mast received in the cut-out and the horizontally opposing edge, thereby allowing the crane to overboard the piling frame in between the cranes even when the cranes are arranged relatively closely together.

Furthermore, the piling frame can be guided while rotating the piling frame overboard, by e.g. pulling the piling frame against a purpose-built round structure that is part of or around the crane mast, so that the piling frame cannot move in the horizontal plane whilst it is rotated by the crane from deck to the position above the water. Thus, dynamic movements in the horizontal plane, for instance caused by environmental factors such as wind, waves, swell, weather, et cetera, can be reduced. The piling frame can for example be pulled against a curved structure around the crane by means of tugger winches whilst rotating the crane, preventing any uncontrolled movement in the horizontal plane.

Preferably, the piling frame comprises a horizontal centroid or center of gravity, wherein the horizontal center of gravity is closer to the horizontal circumference zone at the cut-out than to other circumference zone positions. Another major advantage of the cut-out allowing the vertical crane mast to be received in the cut-out, is that the vertical crane mast and the centroid or center of gravity of the piling frame can be positioned closer together during lifting, which decreases the bending moments on the crane and therefore allows the operator to use cranes with lower load capacity.

For optimal effect, the centroid or center of gravity is preferably positioned adjacent to the horizontal circumference zone at the cut-out, thus allowing the centroid or center of gravity to be positioned virtually next to the vertical crane mast during lifting, further minimizing bending moments.

The horizontal circumference zone may have a polygonal shape with corners and sides connecting the corners, wherein the corners comprise pile sleeves and one of the sides comprises the cut-out. Thus, it is relatively easy and to produce the piling frame with the cut-out.

For instance, the piling frame may comprise a truss structure and the sides are formed by frame members of the truss structure. The cut-out can be advantageously formed by omitting a frame member at the side comprising the cut- out, allowing easy manufacture of the piling frame. In this context “omitting” means that normally, based on the polygonal shape, one would expect a frame member there,

such as a steel tube.

The cut-out is then created by leaving the respective frame member out.

Advantageously, the piling frame comprises three sides and three corners.

Such a piling frame is easy to manufacture, is sturdy, and, for instance, leaving one of the frame members of the truss structure out leads to a relatively large cut-out compared to polygonal shapes with more sides and corners.

Of course, a piling frame with four (perpendicular) sides and four corners is also conceivable.

Preferably, the piling frame comprises a crane connection, wherein the crane connection is closer to the horizontal circumference zone at the cut-out than to other circumference zone positions.

This again advantageously allows the crane to carry the piling frame relatively close to the vertical crane mast during lifting.

Therein, the crane connection is preferably adjacent to the horizontal circumference zone at the cut-out for maximum effect.

Another aspect of the invention relates to a vessel with one or more cranes for lifting an aforementioned piling frame, comprising an aforementioned piling frame.

As explained in the foregoing, when the piling frame is lifted by a crane of the vessel, a vertical mast of the crane is received in the cut-out.

The vessel may comprise a pair of cranes arranged at a same side of the vessel, wherein the distance between the horizontal circumference zone at the cut- out and a horizontally opposing circumference zone position is smaller than a crane distance between the pair of cranes.

Thus, it is possible to a use a relatively large-size piling frame with cranes being positioned relatively closely together.

Basically, it is possible to use relatively larger-size piling frames during overboarding when compared to using “conventional” piling frames, i.e. piling frames without the cut-out.

Such conventional piling frames would simply not fit in between the cranes at similar crane distances when overboarding, forcing the operator to use larger and more expensive vessels.

Another aspect of the invention relates to a method for installing piles in a water body using an aforementioned vessel with an aforementioned piling frame, comprising the steps of: - lifting the piling frame with one of the cranes, wherein a vertical mast of the crane is received in the cut-out, wherein the distance between the horizontal circumference zone at the cut-out and a horizontally opposingcircumference zone position is smaller than a crane distance between the pair of cranes, - rotating the crane lifting the piling frame in between the pair of cranes towards a position above the water body, wherein the vertical mast of the crane 5 remains positioned in the cut-out during the rotating, - lowering the piling frame until the piling frame is positioned on a bottom of the water body, and - using the vessel to install piles in the bottom of the water body, with help of the piling frame. Thus, a relatively smaller vessel can then be used to install the piles. Preferably, the piles are stored onboard the vessel. More preferably, all piles required for the operation are stored onboard the vessel. Advantageously, after forming a foundation of piles on the bottom of the water body, another vessel installs a further water body structure, such as an offshore platform or a wind turbine support structure, on the foundation. By using another vessel to install the further subsea or water body structure the pile installation rate can be significantly increased due to the pile installation vessel and the further subsea structure installation vessel being allowed to work “in series”, as opposed to the conventional installation methods, wherein the pile installation vessel is also used to install the further subsea structure. This greatly increases installation speed, reduces the size of vessel being required for the operation, leading to major cost savings, and furthermore frees up space onboard the pile installation vessel, due to the pile installation vessel not having to carry the further subsea structure. This also enables the pile installation vessel to carry significantly more piles.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be explained hereafter with reference to exemplary embodiments of the piling frame, vessel and method according to the invention and with reference to the drawings. Therein: Figure 1 shows a perspective view of a vessel with an exemplary embodiment of a piling frame according to the invention;

Figure 2 shows a top view of a vessel with another exemplary embodiment of a piling frame according to the invention; Figure 3 shows a vessel installing piles using the piling frame according to the invention; and Figure 4 shows another vessel installing the further subsea structure on the foundation of piles created by the vessel of figure 3.

DETAILED DESCRIPTION Figures 1-4 will be discussed in conjunction. Figure 1 shows a vessel 3, such as an offshore vessel, with two cranes 2 lifting a piling frame 1 according to the invention. Preferably, the cranes 2 are heavy-lift cranes, for instance having a lifting capacity up to 1500 MT. Such cranes 2 are preferred for oversea transport of large and heavy equipment, such as the piles 22 and piling frame 1, onboard heavy lift vessels, such as the vessel 3 as shown. As shown in figure 1, the cranes 2 are preferably used in tandem configuration. The piling frame 1 is lifted by the crane 2 and a vertical mast 6 of the crane 2 is received in a cut-out 5 according to the invention. Preferably, the vertical crane mast 6 is positioned fully within the cut-out 5, i.e. it does not horizontally protrude past an imaginary delimitation line extending between adjacent corners 12 of the piling frame 12. The pair of cranes 2 is arranged at a same side 18 of the vessel 3, such as the starboard or port side of the vessel 3. The distance 19 between the horizontal circumference zone 9 at the cut-out 5 and a horizontally opposing circumference zone position 20 is smaller than a crane distance 21 between the pair of cranes 2, such that the piling frame 1 can be overboarded in between the cranes 2. Several piles 22 are shown stored onboard the vessel 3 in a cargo space. The maximum diameter of the horizontal circumference zone 4 of the piling frame 1 may amount to for instance 10 — 50 m, such as 20 — 40 m. The crane distance 21 may similarly amount to for instance 10 — 50 m, such as 20 — 40 m. The cut-out 5 effectively reduces the distance 19 between the horizontal circumference zone 9 (at the cut-out 5) and a horizontally opposing circumference zone position 20 (i.e. compared to a conventional piling frame without cut-out 5) by for instance 5 — 50 %, more preferably 10 — 50 %, even more preferably 25 — 50%, most preferably 40 — 50 %, such that the piling frame 1 (more easily) fits in between the cranes 2 when overboarding.

The piling frame 1 according comprises a horizontal centroid 7 or center of gravity 8, wherein the horizontal centroid 7 or center of gravity 8 is closer to the horizontal circumference zone 9 at the cut-out 5 than to other circumference zone positions 10, allowing the centroid 7 or center of gravity 8 to be positioned close to the vertical crane mast 6 during lifting. Depending on the specific design of the piling frame 1 and the choice of materials, the centroid 7 and center of gravity 8 may or may not coincide. Most preferably, the centroid 7 or center of gravity 8 is adjacent to the horizontal circumference zone 9 at the cut-out 5 to minimize bending moments exerted on the vertical crane mast 6.

The horizontal circumference zone 4 has a polygonal shape 11 with corners 12 and sides 13 connecting the corners 12, wherein the corners 12 comprise pile sleeves 14 and one of the sides 13, i.e. the side 13 turned towards the crane 2, comprises the cut-out 5. The piling frame 11 comprises a truss structure 15 and the sides 13 are formed by frame members 16 of the truss structure 15, such as steel tubes. The cut-out 5 is formed by omitting a frame member 16 at the side 13 comprising the cut-out 5, i.e. the side 13 turned towards the crane 2. The piling frame 1 as shown in figure 1 comprises three sides 13 and three corners 12, although a piling frame 1 having four sides 13 and four corners 12 as shown in figure 2 - or even more sides and corners, such as six or eight - is also conceivable. The piling frame 1 comprises a crane connection 17, wherein the crane connection 17 is closer to the horizontal circumference zone 9 at the cut-out 5 than to other circumference zone positions 10, to keep the crane connection 17 as closely positioned to the vertical crane mast 6 as reasonably possible. The crane connection 17 therefore is preferably positioned adjacent to the horizontal circumference zone 9 at the cut-out 5.

Alternatively put, the crane 2 outreach minus a distance in the horizontal plane between a vertical centre line through the vertical crane mast 6 and a crane connection or lift rigging connection point 17 of said piling frame 1 is smaller than the crane 2 outreach minus the distance in the horizontal plane between the vertical centre line through the vertical crane mast 6 and the lift rigging connection point of a conventional piling frame without the cut-out.

Figures 3 and 4 depict a method for installing piles 22 in a water body 23 using a vessel 3 according to the invention. As explained in the foregoing - although not shown in figures 3 and 4 - the piling frame 1 is lifted with two cranes 2, wherein a vertical mast 6 of the crane 2 is received in the cut-out 5. The distance 19 betweenthe horizontal circumference zone 9 at the cut-out 5 and a horizontally opposing circumference zone position 20 is smaller than a crane distance 21 between the pair of cranes 2. The crane 2 lifting the piling frame 1 is rotated in between the pair of cranes 2 towards a position above the water body 23, wherein the vertical mast 6 of the crane remains positioned in the cut-out 5 during the rotating. The piling frame 1 is then lowered until the piling frame 1 is positioned on a bottom 24 of the water body, such as the seabed. As shown in figure 3, a vessel 3 is used to install piles 22 in the bottom 24 of the water body 23 to form a foundation 25, with help of the piling frame

1.

As shown in figure 4, after forming a foundation 25 of piles 22 on the bottom 24 of the water body 23, another vessel 26 installs a further water body structure 27, such as an offshore platform or a wind turbine support structure, on the foundation 25. The method allows for very fast “in series” installation of piles 22 in the seabed and further subsea structure 27 on the foundation 25 formed by the piles 22.

It should be clear that the description above is intended to illustrate the operation of preferred embodiments of the invention, and not to reduce the scope of protection of the invention. Starting from the above description, many embodiments will be conceivable to the skilled person within the inventive concept and scope of protection of the present invention.

LIST OF REFERENCE NUMERALS

1. Piling frame

2. Crane

3. Vessel

4. Horizontal circumference zone

5. Cut-out

6. Vertical crane mast

7. Centroid

8. Center of gravity

9. Horizontal circumference zone at the cut-out

10. Other circumference zone positions

11. Polygonal shape

12. Comer

13. Side

14. Pile sleeve

15. Truss structure

16. Frame member

17. Crane connection

18. Side of the vessel

19. Distance between circumference zone at cut-out and opposing circumference zone position

20. Horizontally opposing circumference zone position

21. Crane distance

22. Pile

23. Water body

24. Bottom of the water body

25. Foundation of piles

26. Further subsea structure installation vessel

27. Further subsea structure

Claims

CONCLUSIONS

Piling frame (1) for lifting by a crane (2) of a vessel (3), characterized in that the pile frame, when lifted by the crane, comprises a horizontal circumferential zone (4) with a recess (5 ), wherein the recess is arranged to receive at least partly a vertical crane mast (6) from the crane.

Piling frame (1) according to claim 1, comprising a horizontal geometric center (7) or center of gravity (8), the horizontal center of gravity being closer to the horizontal circumferential zone (9) at the recess (5) than at other circumferential zone positions (10).

Piling frame (1) according to claim 2, wherein the geometric center (7) or center of gravity (8) is adjacent to the horizontal circumferential zone (9) at the recess (5).

Piling frame (1) according to any one of the preceding claims, wherein the horizontal peripheral zone (4) has a polygonal shape (11) with corners (12) and sides (13) connecting the corners, the corners comprising post sleeves (14) and one of the sides comprises the recess (5).

Piling frame (1) according to claim 5, wherein the pile frame comprises a frame construction (15) and the sides (13) are formed by frame elements (18) of the frame construction.

Piling frame (1) according to claim 6, wherein the recess (5) is formed by the omission of a frame element (16) on the side (13) comprising the recess (5).

Piling frame (1) according to one of claims 4 to 6, wherein the pile frame comprises three sides (13) and three corners (12).

Piling frame (1) according to any of the preceding claims, comprising a crane connection (17), wherein the crane connection is closer to the horizontal circumferential zone (9) at the recess (5) than at other circumferential zone positions (10).

Piling frame (1) according to claim 8, wherein the crane connection (17) is adjacent to the horizontal circumferential zone (9) at the recess (5).

Vessel (3) with one or more cranes (2) for lifting a pile-driving frame (1) according to any one of claims 1 to 9, comprising a pile-driving frame according to one of claims 1-9.

Vessel (3) according to claim 10, wherein the pile driver (1) is lifted by a crane (2) and a vertical crane mast (6) of the crane is received in the recess (5).

Vessel (3) according to claim 10 or 11, comprising a pair of cranes (2) mounted on the same side (18) of the vessel, the distance (19) between the horizontal peripheral zone (9) at the recess and a horizontally opposite circumferential zone position (20) is less than a tap distance (21) between the pair of cranes.

Method for installing posts (22) in a water body (23) using a vessel (3) according to claim 12, comprising the steps of: - lifting the pile frame (1) with one or more cranes (2) ), wherein a vertical crane mast (6) of the crane is received in the recess (5), the distance (19) between the horizontal circumferential zone (9) at the recess and a horizontally opposite circumferential zone position (20) being less than a crane distance (21) between the pair of cranes, - rotating the crane that lifts the pile driver between the pair of cranes to a position above the body of water, keeping the vertical crane mast of the crane in the recess during rotation, - lowering from the pile frame until the pile frame is positioned on a bottom (24) of the water body, and - using the vessel to install posts (22) in the bottom of the water body, using the pile frame.

A method according to claim 13, wherein the piles (22) are stored on board the vessel (3).

A method according to claim 13 or 14, wherein, after forming the foundation (25) of piles on the bottom (24) of the water body (23), another vessel (26) a further water body construction (27), such as a offshore platform or a wind turbine support structure, install on the foundation.