Heavy lift crane system installed at lift site

Abstract

A method for installing a heavy lift crane system at a lift site. The crane system comprises a circular slewing track assembly (1) extending over at least one section of slewing arc around a slewing center (2), and a crane (20) having a crane carriage configured to travel on a track arrangement, a main boom (40), a rear tower (50), an adjustable length arrangement (60) between the rear tower (50) and the main boom (40). The method comprises arranging a connector strut (80) below a horizontal rear tower (50), pivotally connecting an upper end of the connector strut (80), pivoting the rear tower (50) to an inclined raised position, arranging a counterweight (70) at a center of gyration (2), placing the connector strut (80) in a substantially vertical orientation above the counterweight (70), connecting a lower end of the connector strut (80) to the counterweight (70), and raising the main boom (40).

Description

Technical Field

[0001] The present invention relates to the field of heavy lift crane systems. Background Art

[0002] In the field of heavy lifting, crane systems are known, for example, as disclosed in WO2010 / 121134, WO2019 / 050405. An example of a heavy lifting mobile crane system is the SK10,000 crane system that has been developed by ALE.

[0003] A heavy lift crane system is disclosed in WO2021 / 140011. The crane system has a track arrangement configured to be mounted on the ground. The arrangement includes a circular slewing track assembly extending around a slewing center over at least one slewing arc. The crane has a crane carriage with a base, a first chassis and a second chassis. The first and second chassis are configured to travel on the track arrangement and support the base thereon. The main boom of the crane is pivotable about a main boom pivot axis relative to the base of the crane carriage and has a main boom tip. The rear tower is pivotable about a rear tower pivot axis relative to the base of the crane carriage and has a rear tower tip. An adjustable length device is provided between the rear tower and the main boom. The crane has a counterweight arranged at the slewing center. The connector strut of the crane is used to suspend the counterweight from the rear tower. As known in the art, the counterweight can then still rest on the ground or on another support. A swivel joint is provided between the counterweight and the rear tower to enable the crane to perform a swivel movement about a swivel center, for example the swivel joint is integrated with the connector strut.

[0004] These cranes are in fact so large that the cranes are usually assembled at the location of the lifting operation, for example at a refinery, a power plant, a production / assembly location of (offshore) wind turbines, etc. Usually, the main boom and the rear tower are each assembled from modules, for example, grid-like modules. For example, the main boom and / or the rear tower are embodied as an A-frame. Other designs are also known, for example a main boom with parallel boom legs connected by support members.

[0005] In an embodiment, the track arrangement may include a load spreading plate on which the track is mounted so that the load is distributed according to the permitted ground pressure. In another design, the track arrangement is mounted on a base, for example for more permanent (longer duration) use of a crane at one location.

[0006] In practice, the main boom, which may be extended by a cantilever, may be more than 100 meters long.For example, it is envisaged that a tall main boom, for example comprising a cantilever, may be used for a wind turbine assembly. Summary of the invention

[0007] An object of the present invention is to improve the installation process of a heavy lift crane system.

[0008] The invention provides a method according to claim 1 .

[0009] A circular slewing track assembly is installed at the lifting site. This can be a fully circular slewing track, a semicircular slewing track or a track extending over another arc segment, for example just more or less than a semicircle. The center of the slewing track forms the slewing center of the crane.

[0010] The slewing track can be configured to be installed at various locations because the crane system is used for lifting operations at these locations. For example, when the crane system is used at a location for a longer period of time, the slewing track can also be permanent. For example, the slewing track can be installed on a foundation such as concrete.

[0011] The assembly of the crane includes mounting the crane carriage on the track arrangement. If only a circular slewing track assembly is present, the carriage is mounted on it. In the case of a more complex track arrangement, such as in WO2021 / 140011, the carriage may also be mounted on a linear track assembly, as discussed herein. However, in many cases, the track arrangement will consist of only a circular slewing track assembly.

[0012] The main boom is assembled to the crane carriage in its horizontal orientation. As discussed, in a practical embodiment the main boom will be modular and assembled from (many) main boom sections, for example as described in WO2021 / 140011. For example, the main boom is an A-frame. In a practical embodiment, the horizontal main boom will rest on a ground support that keeps the main boom horizontal and at a distance above the ground, for example, the assembly of the main boom takes place on the ground support. The cantilever can be assembled to the tip of the main boom.

[0013] The rear tower is assembled to the crane carriage in its horizontal orientation. As discussed, in a practical embodiment, the rear tower will be modular and assembled from (many) rear tower sections, for example as described in WO2021 / 140011. For example, the rear tower is an A-frame. In a practical embodiment, the horizontal rear tower will rest on ground supports that keep the rear tower horizontal and at a distance above the ground, for example, assembly of the rear tower takes place on the ground supports.

[0014] The adjustable length device is arranged between the rear tower and the main boom. For example, as described in WO2021 / 140011, the device may include one or more winch drive cables, for example in a multi-reel arrangement between associated pulleys, between the rear tower and the boom, for example between the rear tower tip and the main boom tip. Possibly, the device includes a dedicated mechanism of winches and cables between the rear towers, which is only used to raise the main boom (e.g. with a cantilever), which mechanism cannot be used during normal operation of the crane.

[0015] Thanks to the method of the invention, the connector strut can be efficiently handled. The connector strut is a critical component having considerable size (particularly length) and mass and can be assembled from strut parts that are stable end to end. The strut can have a plurality of parallel strut parts.

[0016] In a practical embodiment, it is envisaged that the connector struts are moved below the still horizontal rear tower, for example using one or more vehicles, such as self-propelled modular transporters. In another method, the assembly of the connector struts is completed below the still horizontal rear tower.

[0017] In a practical embodiment, before the connector strut is moved or assembled beneath the rear tower, the ground supports on which the rear tower rests are first removed or displaced to clear the area for the connector strut. In a practical embodiment, the adjustable length means are operated, e.g. tensioned, so that the rear tower no longer rests on the ground supports and is effectively suspended (albeit in a horizontal position) by the adjustable length means.

[0018] During the installation configuration, the connector strut is horizontally arranged below the horizontal rear tower.The upper end of the connector strut is then pivotally connected to the rear tower, for example to the tip of the rear tower, around a strut pivot axis.

[0019] In the operational configuration, after which the rear tower is pivoted to an inclined raised position, a connector strut pivotally connected to the rear tower, such as the tip of the rear tower, hangs in a substantially vertical orientation. A counterweight is connected to the lower end of the connector strut, hanging from the rear tower.

[0020] During the pivoting of the rear tower to the tilted position, the connector strut moves from a horizontal position to a substantially vertical position. When the rear tower is raised, the tip of the rear tower is raised. Since the connector strut is pivotally connected and can rotate along a pivot axis defined by the pivot connection, the orientation of the connector strut is changed. This change of orientation is caused, for example, by pulling on its weight or by a driving force that induces the connector strut to rotate.

[0021] In an embodiment, a temporary fastening device is then arranged and / or operated to secure the connector strut along the rear tower. This enables the connector strut to be raised by the process step of pivoting the rear tower to its raised position. For example, temporary fastening involves the use of an auxiliary winch of a crane system and a corresponding winch drive cable, which extends from the rear tower and is attached to the connector strut at a position remote from its upper end, such as at or near its lower end. The cable can be used to pull the connecting rod towards the rear tower. Other methods of providing temporary fastening are also envisioned, for example involving the use of slings, locking devices, etc.

[0022] In an embodiment, the rear tower may be pivoted to a raised position using an adjustable length device.Other methods are also contemplated, including, for example, a dedicated erection mechanism for the rear tower.

[0023] In another embodiment, - after pivotally connecting the upper end of the connector strut to the horizontal rear tower, - the connector strut is supported at its lower end by the vehicle, wherein the method then comprises:

[0024] - pivoting the rear tower to an inclined raised position wherein the lower end of the connector strut initially remains supported by the vehicle moving away from the swing track assembly until the lower end of the connector strut is lifted away from the vehicle,

[0025] - Place the counterweight at the center of rotation,

[0026] - orienting the connector struts substantially vertically above the counterweight,

[0027] -Attach the lower end of the connector strut to the counterweight,

[0028] - Raising the main boom, for example by operating an adjustable length device between the rear tower and the main boom.

[0029] Here, the vehicle may be a vehicle that has been used to move the connector strut into a position below the horizontal rear tower.

[0030] In a further development of the method, - before pivoting the rear tower into the tilted raised position, - the lower end of the connector strut is connected to the rear tower via a sling or cable, thereby limiting the pivoting angle of the connector strut relative to the rear tower, and wherein the method then comprises:

[0031] - pivoting the rear tower to an inclined raised position, preferably by operating an adjustable length device between the rear tower and the main boom, wherein the lower end of the connector strut initially remains supported by the vehicle moving away from the swing track assembly until the lower end of the connector strut is lifted away from the vehicle when the sling or cable limits the pivoting angle of the connector strut,

[0032] - Place the counterweight at the center of rotation,

[0033] - for example by pivoting the rear tower so that the connector strut is in a substantially vertical orientation above the counterweight,

[0034] -Attach the lower end of the connector strut to the counterweight,

[0035] - Raising the main boom, for example by operating an adjustable length device between the rear tower and the main boom.

[0036] Since the rear tower in its horizontal orientation effectively extends beyond the slew center, the stage of arranging the counterweight at the slew center can be easily performed once the rear tower is in this raised position, so that the connector strut is spaced from the location where the counterweight is to be arranged.

[0037] The stage of arranging the ballast weight may include assembling the ballast weight from components such as steel plates, containers filled with ballast material, and the like.

[0038] Once the counterweight has been completed, the connector strut is brought into a position that allows its lower end to be connected to the counterweight. For example, the connector strut is released from the rear tower so that the strut can be swung about its pivot connection to a generally vertical orientation, such as a fully vertical orientation. Considering the size and mass of the connector strut, an auxiliary winch and corresponding cables may be employed to cause a controlled swinging of the connector strut.

[0039] The lower end of the connector strut is then connected to the counterweight. Once this is achieved, the main boom - possibly with a cantilever arrangement at its tip - can be raised by operating an adjustable length arrangement between the rear tower and the main boom.

[0040] The installation process of the present invention is effective and reliable.

[0041] In an embodiment, the horizontal main boom rests on a ground support that keeps the main boom horizontal and at a certain distance above the ground, for example, assembly of the main boom occurs on the ground support, and / or the horizontal rear tower rests on a ground support that keeps the rear tower horizontal and at a certain distance above the ground, for example, assembly of the rear tower occurs on the ground support.

[0042] In an embodiment, before the connector strut is moved or assembled under the rear tower, the ground supports on which the rear tower rests are first removed or displaced to clear an area for the connector strut, For example, the adjustable length device is operated so that the rear tower no longer rests on the ground supports and is effectively suspended in a horizontal position by the adjustable length device, and then the ground supports are displaced or removed to clear an area under the horizontal rear tower for the connector strut.

[0043] In an embodiment, temporary fastening involves using an auxiliary winch of the crane system and a corresponding winch drive cable, the winch drive cable extending from the rear tower and attached to the connector strut away from the upper end of the connector strut, for example at or near the lower end of the connector strut, wherein the cable is used to hold the connector strut along the rear tower, for example to pull the connector strut towards the rear tower, for example against the rear tower.

[0044] In an embodiment, an auxiliary winch and corresponding cable are used to controllably swing the connector strut 80 away from the rear tower, for example, using the winch to temporarily secure the connector strut.

[0045] The invention also relates to a heavy lift crane system according to claim 10 to be installed at a lifting site. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention will now be discussed with reference to the accompanying drawings. In the drawings:

[0047] Figure 1 An example of an installation of a heavy lift crane system according to the invention is shown, wherein the crane is arranged on a circular swing track assembly,

[0048] Figure 2 Shown in side view Figure 1 The crane,

[0049] Figure 3 shows the installation of the crane carriage on the circular swing track assembly and the assembly of the main boom to the crane carriage in a horizontal orientation,

[0050] Figure 4 Shows the assembly of the rear tower to the crane carriage in a horizontal orientation and the provision of an adjustable length device between the rear tower and the main boom,

[0051] Figure 5 Shown is the tensioning of the adjustable length device and the removal of the support from beneath the still horizontal rear tower.

[0052] Figure 6 showing the arrangement of the connector strut below the horizontal rear tower, pivotally connecting the upper end of the connector strut to the horizontal rear tower, and temporarily fastening the connector strut along the rear tower,

[0053] Figure 7 The rear tower is shown pivoted to a tilted raised position by operating an adjustable length device between the rear tower and the main boom,

[0054] Figure 8 The counterweight is arranged at the center of rotation, the temporarily fastened connector strut is loosened and the connector strut is swung to a substantially vertical orientation, and the lower end of the connector strut is then connected to the counterweight,

[0055] Fig. 9 Another embodiment for arranging the connector strut below the horizontal rear tower and pivotally connecting the upper end of the connector strut to the horizontal rear tower is shown.

[0056] Fig.10 Shown in Fig. 9 Then the rear tower is pivoted to the tilted raised position by operating the adjustable length device between the rear tower and the main boom.

[0057] Fig.11 Shown in Fig.10 The counterweight is then arranged at the center of rotation, the connector strut is brought over the counterweight, and the lower end of the connector strut is then connected to the counterweight. DETAILED DESCRIPTION

[0058] Figure 1 and Figure 2 Shown is a heavy lift crane system installed at a lift site.

[0059] The crane system comprises a track arrangement mounted on the ground. Here, the track arrangement consists of a circular slewing track assembly 1 extending on a slewing arc around a slewing center 2. The slewing track comprises, for example, a pair of track members, such as slide rails.

[0060] The crane system further comprises a crane 20. The crane comprises:

[0061] a crane carriage comprising a base 30, a first chassis 31 and a second chassis 31, the first chassis and the second chassis being configured to travel on a rail arrangement and to support the base 30 thereon,

[0062] a main boom 40 which is pivotable relative to the base of the crane carriage about a main boom pivot axis 41 and has a main boom tip 42,

[0063] a rear tower 50 which is pivotable relative to the base 30 of the crane carriage about a rear tower pivot axis 51 and has a rear tower tip 52,

[0064] - an adjustable length device 60, which is located between the rear tower 50 and the main boom 40,

[0065] - a counterweight 70, which is arranged at the center of rotation 2,

[0066] - A connector strut 80 which suspends the counterweight 70 from the rear tower 50. As shown and known in the art, the counterweight 70 may then still rest on the ground or on another support.

[0067] The connector strut is pivotable relative to the rear tower 50. The rear tower has a part in its upper part adapted to engage with another part of the upper end of the connector strut. The two parts form a pivotable connection and define a pivot axis 53.

[0068] A swivel joint 82 is provided between the counterweight 70 and the rear tower 50 to enable the crane to perform a swivel motion around the swivel center 2, for example, the swivel joint is integrated with the connector strut or with the connector 71 of the counterweight 70. In another embodiment, the counterweight 70 itself can rotate with the swivel motion of the crane, for example, it is mounted on a circular counterweight track.

[0069] The crane 20 is used, for example, for the production of wind turbines, which are to be mounted on a floating foundation by means of the crane 20 and then towed out to an offshore wind farm.

[0070] The crane 20 depicted is also provided with a boom 55, which is pivotally mounted to the tip of the main boom 50, as is known in the art. The boom 55 is held in its desired orientation by a support mechanism, which here comprises a lower boom strut 56, a lower brace 57, an upper boom strut 58 and an upper brace 59. The boom struts 56, 58 are each connected at an inner end to the tip of the main boom, as is known in the art. A variable length mechanism 65 is present between the struts 56, 58.

[0071] The lifting system of the crane 20 is shown to include winch-driven lifting cables 90 suspended in a multi-reel arrangement from a pulley assembly on the tip of the boom 55 to, for example, a lifting block 91 having a hook. For example, another lifting system of the crane includes winch-driven lifting cables suspended from a pulley assembly on the tip of the main boom in a multi-reel arrangement to, for example, a lifting block having a hook.

[0072] In an embodiment, the crane is provided with a guying system, for example comprising one or more guying tracks along the main boom, on which one or more guying trolleys travel, as known in the art, for example, in view of maneuvering wind turbine blades.

[0073] As known in the art, and preferably, the tracks of the track of the circular slewing track assembly can be implemented for sliding. For example, each track includes a sliding surface arranged between two slide rails, wherein a sliding actuator is engageable with one or both of the slide rails and with the carriage to advance the crane on the corresponding track. In another embodiment, the track engaging member is embodied as a wheel, which is configured to roll on the rolling surface of the track, for example similar to a railway track.

[0074] The main boom 40 is preferably modular, more preferably having two lattice-like legs, for example an A-frame as shown here.

[0075] The rear tower 50 is preferably modular, more preferably having one or two lattice-like legs, such as an A-frame as shown here.

[0076] The counterweight 70 may consist of, for example, steel elements arranged on a platform, in a hanger, etc. At the top of the counterweight 70 , there is a connector 71 for a connector strut 80 .

[0077] Reference Figures 3 to 8 , the relevant stages of installing the crane 20 will be discussed.

[0078] Figure 3 The crane carriage 30 is shown mounted on the circular slewing track assembly 1, and the main boom 40 is assembled in a horizontal orientation to the crane carriage 30. As shown, the main boom 40 rests on ground supports 45, which hold the main boom at a distance (here several meters) above the ground and in a horizontal orientation.

[0079] For purposes of illustration, a person is shown on the track assembly 1 below the carriage.

[0080] Figure 4 The rear tower 50 is shown assembled to the crane carriage 30 in a horizontal orientation, and an adjustable length device 60 is provided between the rear tower 50 and the main boom 40. The device 60 includes one or more winches 61 on the rear tower 50 and one or more winch drive cables 62 extending from the tip of the rear tower 50 and connected to the main boom 40 at this stage. The rear tower rests on ground supports 54.

[0081] Figure 5 Tensioning the adjustable length device 60 and removing the support 54 from beneath the still horizontal rear tower 50 to clear an area for the connector strut 80 is shown.

[0082] Figure 6 The connector struts 80 are shown arranged below the horizontal rear tower 50. Here, two self-propelled modular transporters 100 are used to transport the struts 80 resting thereon. Once positioned below the rear tower 50, the upper ends of the struts 80 are pivotally connected to the horizontal rear tower.

[0083] The strut 80 is temporarily fastened to the rear tower, here involving the use of an auxiliary winch 95 of a crane system and a corresponding winch drive cable 96, which extends from the rear tower 50 and is attached away from its upper end (here at its lower end) to the connector strut 80. The cable 96 serves to hold the connector strut 80 along the rear tower, here in order to pull the connector strut towards, for example, against the rear tower 50.

[0084] Figure 7The rear tower 50 and the temporarily secured connector strut 80 are shown pivoted to the tilted raised position by operating the adjustable length device 60 between the rear tower and the main boom 40. This disengages the rear tower from the slewing center so that the counterweight 70 can now be positioned as shown. Figure 8 The arrangement shown is at the slewing center 2. The raised position of the rear tower 50 enables the temporary fastening of the connector strut 80 to be loosened and the connector strut 80 to be swung to a substantially vertical orientation, followed by connecting the lower end of the connector strut to the counterweight. Here, the swinging of the strut 80 is controlled by the operation of the winch 95.

[0085] Once the connector struts 80 are secured to the counterweight, the main boom (here with a cantilever) is raised by operating the adjustable length device 60 between the rear tower and the main boom 40. The crane system is now ready for use.

[0086] Now refer to Figures 9 to 11 The second embodiment of the present invention is discussed. Here, components are indicated by the same reference numerals as in the first embodiment.

[0087] Fig. 9 The connector struts 80 are shown transported on two transporters 100 to a position beneath a horizontally oriented rear tower 50, which rests on ground supports 54. The transporters 100 are moved between the supports 54, enabling the rear tower 50 to remain supported thereon during this stage.

[0088] Fig. 9 The upper end of the connector column 80 is shown being lifted by a mobile crane 200 having a lifting cable 201 so that the upper end of the column 80 can be connected to the tip 52 of the rear tower. The lower end of the column 80 is held on a transport device 100.

[0089] Fig. 9 It is shown that during the subsequent step of raising the rear tower 50, the auxiliary bracket 130 is used to provide a control rod for the device 60.

[0090] Fig.10 The raising of the rear tower 50 is shown when the support column 80 is pivotally connected to the rear tower 50 at its upper end. The connector support column 80 is shown supported at its lower end by the transport device 100. Then, the raising step includes pivoting the rear tower 50 to an inclined raised position, for example, by operating the adjustable length device 60 between the rear tower and the main boom. Here, the lower end of the connector support column 80 initially remains supported by the transport device 100 moved away from the swing track assembly 1 until the lower end of the connector support column is lifted off the transport device 100.

[0091] Fig.10It is shown that - before pivoting the rear tower 50 to the tilted raised position - the lower end of the connector strut 80 is connected to the rear tower via a sling 85 or cable, thereby limiting the pivoting angle of the connector strut 80 relative to the rear tower.

[0092] Initially, the sling 85 Fig.10 As shown, the slings are loose, but as the rear tower is pivoted upward and the transport device 100 moves away from the swing track assembly 1, the slings also become loose. Fig.10 When the process step of raising the rear tower 50 is continued, the lower end of the connector support 80 is lifted away from the transport device 100 because the sling 85 limits the pivot angle of the connector support relative to the rear tower 50 .

[0093] Fig.11 The rear tower 50 is shown being raised to a certain inclination so that the overhanging connector strut 80 is completely away from the rotation center 2, which enables the counterweight 70 to be arranged at the rotation center 2. Once the counterweight 70 is completed, the rear tower 50 is lowered slightly, such as Fig.11 As shown, the connector strut is brought to a substantially vertical orientation above the counterweight. The lower end of the connector strut 80 is then connected to the connector 71 of the counterweight 70. In a further installation process, the main boom 40 can be raised by operating the adjustable length device 60 between the rear tower and the main boom, such as a dedicated mechanism thereof.

Claims

1. A method for installing a heavy lift crane system at a lift site, the crane system comprising: - a track arrangement configured to be mounted on the ground and comprising: - a circular orbital assembly (1) extending about a center of rotation (2) over at least one arc of rotation, - a crane (20) comprising: - a crane carriage comprising a base (30), a first chassis (31) and a second chassis (32), the first chassis and the second chassis being configured to travel on a rail arrangement and to support the base (30) thereon, a main boom (40) which is pivotable relative to the base of the crane carriage about a main boom pivot axis (41) and has a main boom tip (42), a rear tower (50) which is pivotable relative to the base (30) of the crane carriage about a rear tower pivot axis (51) and has a rear tower tip (52), - a device (60) capable of adjusting the length, located between the rear tower (50) and the main boom (40), - a counterweight (70) configured to be arranged at the center of rotation, wherein the crane comprises a connector strut (80) for suspending a counterweight from the rear tower, and wherein, preferably, a swivel joint (82) is provided between the counterweight and the rear tower (50) to enable the crane to perform a swivel movement about a swivel center (2), Wherein, the method comprises: - Install the circular slewing track assembly (1) at the lifting site, - The assembly of the crane (20) comprises: - mounting the crane bracket (30, 31, 32) on a track arrangement, for example on a circular rotary track assembly (1), - Assembling the main boom (40) to the crane carriage in a horizontal orientation, - assembling the rear tower (50) to the crane carriage in a horizontal orientation, - a device (60) capable of adjusting the length is provided between the rear tower and the main boom, - arranging the connector strut (80) in a horizontal orientation below the horizontal rear tower (50), - pivotally connecting the upper end of the connector strut (80) to the horizontal rear tower (50), - pivoting the rear tower (50) to an inclined raised position, wherein the connector strut (80) is pivotally connected at its upper end to the rear tower via the strut pivot axis (53), - arranging the counterweight (70) at the center of rotation (2), - position the connector support (80) above the counterweight, - connect the lower end of the connector strut (80) to the counterweight (70), - Raise the main boom (40).

2. The method according to claim 1, wherein: - after pivotally connecting the upper end of the connector strut (80) to the horizontal rear tower (50), - the connector strut (80) is temporarily fastened along the rear tower (50), and then the method comprises: - pivoting the rear tower (50) with the connector strut (80) already temporarily fastened to the rear tower (50) to a tilted raised position, - arranging the counterweight (70) at the center of rotation (2), - loosening the temporary fastening of the connector strut (80) and swinging the connector strut (80) to a substantially vertical orientation above the counterweight, - connect the lower end of the connector strut (80) to the counterweight (70), - Raise the main boom (40).

3. The method according to claim 1, wherein: - after pivotally connecting the upper end of the connector strut (80) to the horizontal rear tower (50), - the connector strut (80) is supported at its lower end by the vehicle (100), then the method comprises: - pivoting the rear tower (50) to an inclined raised position wherein the lower end of the connector strut (80) initially remains supported by the vehicle moving away from the swing track assembly until the lower end of the connector strut is lifted away from the vehicle, - arranging the counterweight (70) at the center of rotation (2), - orienting the connector strut (80) substantially vertically above the counterweight, - connect the lower end of the connector strut (80) to the counterweight (70), - Raise the main boom (40).

4. The method according to claim 3, wherein: - before pivoting the rear tower (50) to the tilted raised position, - the lower end of the connector support (80) is connected to the rear tower via a sling or cable, thereby limiting the pivoting angle of the connector support (80) relative to the rear tower, and then the method comprises: - pivoting the rear tower (50) to an inclined raised position, wherein the lower end of the connector strut (80) initially remains supported by the vehicle (100) moving away from the swing track assembly until the lower end of the connector strut is lifted away from the vehicle when the sling or cable limits the pivoting angle of the connector strut, - arranging the counterweight (70) at the center of rotation (2), - for example by pivoting the rear tower so that the connector strut (80) is in a substantially vertical orientation above the counterweight, - connect the lower end of the connector strut (80) to the counterweight (70), - Raise the main boom (40).

5. The method according to any one or more of claims 1 to 4, wherein: The horizontal main boom (40) rests on ground supports that keep the main boom horizontal and at a distance above the ground, for example, the assembly of the main boom takes place on ground supports (45), and / or Therein, a horizontal rear tower (50) rests on a ground support (54) that keeps the rear tower horizontal and at a distance above the ground, for example, the assembly of the rear tower takes place on the ground support.

6. The method according to any one or more of claims 1 to 5, wherein: Prior to moving or assembling the connector strut (80) beneath the rear tower, the ground supports (54) upon which the rear tower (50) rests are first removed or displaced to clear the area for the connector strut (80) for transport, such as on one or more vehicles (100).

7. The method according to claim 6, wherein: The adjustable length device (60) is operated so that the rear tower no longer rests on the ground supports (54) and is effectively suspended in a horizontal position by the adjustable length device, and the ground supports are then displaced or removed to clear the area below the horizontal rear tower for the connector struts.

8. The method according to claim 2, wherein: Temporary fastening involves the use of an auxiliary winch (95) of the crane system and a corresponding winch drive cable (96), which extends from the rear tower and is attached to the connector strut away from the upper end of the connector strut, for example at or near the lower end of the connector strut, wherein the cable is used to hold the connector strut along the rear tower, for example to pull the connector strut towards the rear tower, for example against the rear tower.

9. The method according to any one or more of claims 1 to 8, wherein: An auxiliary winch (95) and corresponding cable (96) are used to cause controlled pivoting movement of the connector strut (80) relative to the rear tower, such as the winch of claim 8.

10. A heavy lift crane system to be installed at a lifting site, the crane system comprising: - a track arrangement configured to be mounted on the ground and comprising: - a circular orbital assembly (1) extending about a center of rotation (2) over at least one arc of rotation, - a crane (20) comprising: - a crane carriage comprising a base (30), a first chassis (31) and a second chassis (32), the first chassis and the second chassis being configured to travel on a rail arrangement and to support the base (30) thereon, a main boom (40) which is pivotable relative to the base of the crane carriage about a main boom pivot axis (41) and has a main boom tip (42), a rear tower (50) which is pivotable relative to the base (30) of the crane carriage about a rear tower pivot axis (51) and has a rear tower tip (52), - a device (60) capable of adjusting the length, located between the rear tower (50) and the main boom (40), - a counterweight (70) configured to be arranged at the center of rotation (2), wherein the crane includes a connector strut (80) for suspending the counterweight from the rear tower, In the mounted configuration, the connector strut is arranged horizontally below the rear tower in a horizontal orientation of the rear tower and is pivotally connected to the rear tower, for example to the tip of the rear tower, and pivots about a rear tower upper end pivot axis (53), wherein in an operational configuration, the upper end of the connector strut (80) is pivotally connected to the rear tower in a substantially vertical orientation, such as from a tip of the rear tower, and wherein the counterweight (70) is connected to the lower end of the connector strut so as to depend from the rear tower.

11. The heavy lift crane system of claim 10, wherein: Temporary fastening means (95, 96) are provided for temporarily fastening the connector strut along the horizontal rear tower, so that the rear tower and the connector strut (80) temporarily fastened thereto can be pivoted to an inclined raised position, for example, by operating a length-adjustable device (60) between the rear tower and the main boom.

12. The heavy lift crane system of claim 11, wherein: The temporary fastening means comprises an auxiliary winch (95) of the crane system and a corresponding winch drive cable (96) extending from the rear tower and attachable to the connector strut (80) at a position remote from the upper end of the connector strut.

Images