Patent Description:
Known in practice are vibrating or hammering devices for placing a foundation pile on which a construction such as wind turbine can be mounted. To enable vibrating the pile into the ground a so-called vibrator block is usually applied. This requires a correct positioning of the associated vibration block and the foundation pile. In practice this also often involves lifting and/or so-called up-ending of the foundation element.

<CIT> discloses a vibrating device and method for inserting a foundation element into the ground. This document also illustrates lifting and up-ending of a foundation element with a clamping mechanism that fixedly clamps the foundation element.

The positioning before the actual insertion of the foundation element in the ground requires substantial forces to act on the foundation element, especially during lifting and/or up-ending of the foundation element. This may result in damaging the foundation element, which may include fatigue damage. Also, in case a coating, in particular an offshore coating, is provided to the foundation element there is a substantial risk that lifting and/or up-ending may damage this coating. This may significantly reduce the lifespan of the foundation element.

An object of the present invention is to obviate or reduce one or more of the above mentioned problems.

This object is achieved with the clamping device according to claim <NUM> that can be used for a vibrating or hammering device for inserting a foundation element having a flange into the ground.

The clamping device according to the invention is configured for clamping on a flange of the foundation element. This foundation element may relate to different elements, specifically including a pile, tube, pipe and the like. The foundation element is preferably provided with a flange that is attached to the foundation element at or close to one of its outer ends. This flange has an upper and lower surface as seen in the inserted position of the foundation element.

The clamping device according to the invention is provided with at least a first and second clamp bodies that engage the first and second flange surfaces. This engagement can be direct or indirect using intermediate parts or components.

To enable the clamping device to engage with one of the clamp bodies on a first surface of the flange and with another clamp body on a second surface of the flange a positioning drive is provided. This positioning drive enables a relative movement of the first clamp body to the second clamp body in a positioning direction. This enables (partly) positioning the clamping device below the flange. The positioning drive is further capable of moving the clamp bodies in a desired position such that a clamping movement in a clamping direction can be initiated using the clamping drive. The clamping drive enables a relative movement of the first and second clamp bodies to enable engagement of the clamp bodies on the respective flange surfaces.

The clamp bodies engage the flange in a clamping direction that is substantially transversal to the positioning direction. In the operational position of the foundation element the positioning direction substantially corresponds to a horizontal direction and the clamping direction substantially corresponds to a vertical direction.

Clamping a flange of the foundation element prevents damaging the foundation element itself. Also, in case a coating is provided to the foundation element, the risk of damaging the coating is significantly reduces. Furthermore, the clamping device reduces the fatigue damage of the foundation element. This significantly increases the lifespan of the foundation element.

In addition, the clamping device according to the present invention enables a failsafe operation and failsafe lifting and/or up-ending of the foundation element.

In a presently preferred embodiment the positioning drive and/or clamping drive comprise one or more hydraulic cylinders. It will be understood that other drive systems can also be envisaged in accordance to the present invention.

In a presently preferred embodiment the positioning drive comprises a sliding cylinder.

Providing a sliding cylinder enables a relative movement between the first and second clamp bodies in the positioning direction. This enables positioning of the clamping device relative to the flange of the foundation element and more specifically the correct positioning of the clamp bodies to enable starting the clamping movement. Preferably, the clamp body slides, or is otherwise moved, around the flange to enable a direct clamping of the flange between the clamp bodies. This enables positioning of the vibrating or hammering device relative to the foundation element. Furthermore, it enables lifting and/or up-ending the foundation element.

In a presently preferred embodiment of the invention the clamping drive comprises a two-stage drive system, wherein the first stage enables providing contact between at least one of the clamp bodies and the respective flange surface, and the second stage enables providing a clamping force on the flange.

The clamping drive enables providing the actual direct or indirect engagement of the clamp bodies to the flange, specifically the upper or lower surface thereof. Preferably, the clamping provides a pre-tension and/or clamping force to enable safe operation. As a further effect this pre-tension and/or clamping force reduces variation in tension on the flange. This reduces the risk of damage, including fatigue damage, of the foundation element. In addition, it contributes to a failsafe operation.

Preferably, in one of the embodiments of the invention, the two-stage drive system comprises a hydraulic cylinder having a first chamber configured for moving the first clamp body relative to the second clamp body in the first stage, and a second chamber configured for clamping the flange of the foundation element between the first and second clamp bodies in the second stage and providing a pre-tension. This two-stage drive system enables a step-wise clamping operation wherein the clamping movement and the pre-tensioning are at least partly separated. This preferably enables a design of the first chamber and second chamber that is directed to their specific task. This improves the operation and reduces the risk of damaging the foundation element or flange thereof.

In particular, the first stage has a specific first stroke that is preferably defined by the housing of the clamping device. This enables an effective clamping movement, where after the second stage having a second stroke is designed for optimal pre-tensioning and providing of the desired clamping force.

In one of the presently preferred embodiments of the invention, the first and second chambers are activated separately. In this embodiment, the first chamber is responsible for the clamping movement wherein the clamp bodies move toward each other and engage the flange. Preferably, the movement is such that contact between the clamp bodies and the flange is (just) prevented. The first stage preferably aims at performing a significant part (sub-stroke of first stage) of the stroke of the clamp bodies relative to the flange. The second chamber is responsible for providing the actual clamping force and provides a desired pre-tension. Preferably, the sub-stroke of the second stage is limited to a few mm. In operation, load variation basically only influences the pressure in the second chamber. The first chamber substantially remains at its constant pressure and, therefore, remains its stiffness. Pressure variations are limited to the second chamber. Therefore, variation is restricted to the relatively small volume of the second chamber as compared to conventional systems. This reduces any volume changes in operation as a result of pressure variation. Experiments showed a reduction in the range of <NUM> to <NUM>% as compared to a conventional system. This provided a higher stiffness over the overall system. This significantly reduces the fatigue damage of the clamping device and the flange. In a presently preferred embodiment, in (vibrating/hammering) operation the pressure in the second chamber is reduced, while the pressure in the first chamber is significantly maintained. This reduces the risk of stretching the frame of the clamping device.

In a presently preferred embodiment the clamping device further comprises a controlled non-return valve to maintain pressure in the first and/or second chamber.

Providing such valve guarantees that during lifting and/or up-ending the clamping of the clamping device on the flange of the foundation element is maintained even in case of a failure of the hydraulic system, for example. This further improves the failsafe system and prevents disconnection of the foundation element from the clamping device. Therefore, this increases the safety when working with a foundation element.

In a presently preferred embodiment the clamping device further comprises a pressure system configured for increasing the clamping force in response to lifting and/or up-ending forces.

In operation, when the actual external forces increase above the pre-tension applied to the clamping device the operational pressure in the cylinder will reduce. In this embodiment this reduction is compensated by providing additional pressure. When the operational forces are removed from the system the increased pressure in the clamping device will remain. This is preferably achieved by using one or more controlled non-return valves, or other suitable means. The advantage hereof is that the operational pressure is partly provided by the lifting and/or up-ending and/or inserting operation(s). This renders the operation very efficient. Also, this enables providing additional pressure in case of oil leakage and/or wear of parts, for example. This further increases the operational safety when working with foundation elements.

In a further preferred embodiment of the invention the clamping device further comprises slide elements configured for connecting the clamping device with a sliding connection to a base frame of the vibrating or hammering device.

Providing slide elements enables to connect the clamping device to a base frame effectively. Preferably, this obviates the need for bolts to connect the clamping device to the base frame. This contributes to a fail-safe system and operation. In addition, the slide elements enable the (rigid) base frame to support the (rigid) stationary part of the clamping device that is preferably provided with the drive cylinder(s). This results in relatively stable operating pressures in the cylinder(s) and/or reduces the fatigue damage of the clamping device and/or pile.

In such embodiment it is presently preferred that the top clamping surface (as seen in a situation of use) of a clamp body is not pushed towards the pile flange when initiating the actual clamping. Instead, the bottom clamping surface of a clamp body is pushed up towards and against the flange bottom. This is initiated by pushing the first and second clamp body up against the base frame. This eliminates negative effects of flexibility of the clamping system, thereby decreasing fatigue damage of the flange significantly.

Preferably, in one of the presently preferred embodiments, the second (sliding) clamp body of the clamping device is operatively connected to the base frame with sliding elements. This provides an effective clamping. More preferably, interaction between one or both clamp bodies and slide elements is configured to enable (at least) one of the clamp bodies to move towards the other clamp body when initiating/starting the clamping action. This interaction provides some play at the clamping end of the clamp body and fixates the other end, thereby enabling a small rotational movement of the clamp body when initiating the clamping. This provides an effective clamping, especially on the inner flange that extends inwardly from the side wall of a foundation element, for example. This provides a sigficant reduction of the fatigue damage as compared to conventional clamping devices. It was also shown that such small rotational movement of one of the clamp bodies performed better as compared to a pure (vertical) translational movement of the clamp bodies in an alternative embodiment.

In a further preferred embodiment the clamping device comprises a wedge lock in relation to at least one of the clamp bodies.

The wedge lock is preferably provided at a contact surface of the clamp body with the flange surface. The wedge element guarantees a substantially robust contact surface. This provides an additional safeguard. In addition, wear is reduces. Also, the pre-tension can be applied more accurately. The wedge lock is preferably used in combination with the two-stage system.

One of the advantages of providing a wedge lock is that it provides a very stiff and self locking mechanism, which increases the efficiency of the clamp and reduces the fatigue damage.

In a further preferred embodiment of the invention the clamping device further comprises a pile guide configured for guiding the positioning of the clamping device relative to the foundation element.

The pile guide enables a self-aligning effect when positioning the clamping device relative to the foundation element with the flange. This enables an easier positioning of the clamping device relatively to the foundation element.

In a presently preferred embodiment the pile guide, or a number of pile guides, is provided that enables self-aligning of the clamp bodies with the respective flange surfaces in a clamping state of the clamping device.

Preferably, the pile guide is arranged to the frame of the clamping device and/or vibrating/hammering device such that in a clamping state of the clamping device the clamp bodies remain in engagement with the respective flange surfaces. In a presently preferred embodiment this is achieved by arranging the one or more pile guides such that contact between the flange and a clamp bodies is maintained and undesired sliding movement is restricted even in case of a sliding movement of the clamp bodies relative to the flange in a positioning direction. Preferably, the pile guide is arranged such that any retracted clamp body will not be stuck behind the flange when removing the clamping device from the foundation element. This contributes to a failsafe system also in case of a pressure loss during the lifting and/or upending of the foundation element.

Optionally, separate elements can be provided such as a first pile guide for self-alignment and a second pile guide for sliding movement restriction.

In one of the presently preferred embodiments of the invention the pile guide is embodied as a pile guide web construction. This web construction enables connecting individual pile guides together in a construction. Such construction contributes to the overall strength and stability of the system.

In a further preferred embodiment of the invention the pile guide comprises a pile guide contact pad. This contact pad prevents damage to the foundation element during the positioning of the clamping device relative to the foundation element.

According to the invention, the clamping device comprises a pressure relief valve configured to prevent overloading in the operational/driving state of the clamping device wherein the foundation element is inserted into the ground.

Providing a pressure relief valve provides a reduction of unnecessary forces acting on the flange and/or foundation element in a driving state. In one of the presently preferred embodiments this is achieved by reducing the pressure from the second chamber in the two-stage system.

Optionally, strain gauges and/or pressure sensors are provided to monitor the pre-tension during driving in the driving state. This further improves the safety when working with the clamping device.

In a further preferred embodiment the clamping device further comprises a sensor or indicator configured for determining the position of the clamp bodies.

The sensor or indicator detects the relative position of one or more of the clamp bodies to the flange. The sensor may comprise a so-called inductive sensor. In addition or as an alternative the indicator may comprise a so-called visual indicator. In a presently preferred embodiment a combination is applied of both a sensor and an indicator to further improve the safety of working with the clamping device of the invention.

In a further preferred embodiment of the invention at least one of the clamp bodies of the clamping device comprises a contact pad.

The contact pad is preferably a soft pad or soft guide and further reduces the risk of damaging the flange and/or foundation element. This increases the lifespan of the foundation element.

The invention further relates to a vibrating or hammering device for inserting a foundation element into the ground, with the device comprising a clamping device in one of the embodiments of the invention.

The vibrating or hammering device provides the same or similar effects and advantages as described in relation to the clamping device.

In a presently preferred embodiment the vibrating or hammering device comprises two or more clamping devices, such as <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> clamping devices for an individual foundation element. It will be understood that another number of clamping devices can also be envisaged in relation to of vibrating or hammering device. Optionally, in accordance with a particular embodiment of the invention there can be provided a unitary central clamping device that preferably extends around a substantial part of the circumference of the foundation element.

The invention further also relates to a method for inserting a foundation element into the ground, with the method comprising the steps of:.

The method provides the same or similar effects or advantages as mentioned in relation to the clamping device and/or the vibrating or hammering device. Preferably, the clamping is performed on a flange that extends inwardly from a foundation element. The (lower) clamping body is positioned by performing a translational movement. In one of the presently preferred embodiments of the invention, when the clamping is initiated, one of the clamp bodies makes a (small) rotational movement to achieve the actual clamping. It was shown that such small rotational movement of one of the clamp bodies performed better as compared to a pure (vertical) translational movement of the clamp bodies.

In a presently preferred embodiment the method further comprises the step of up-ending the foundation element. This enables an effective operation when inserting a foundation element into the ground.

Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which:.

Clamping device <NUM>' (<FIG>) is used for vibrating or hammering device <NUM> comprising vibrator block <NUM> that is connected to base frame <NUM>. In the illustrated embodiment vibrator block <NUM> is provided with hoist <NUM> to enable lifting and/or up-ending. Clamping device <NUM>' is provided with frame <NUM>, first clamp body <NUM> and second clamp body <NUM>.

In the illustrated embodiment vibrating or hammering device <NUM> is provided with <NUM> clamping devices <NUM>' (<FIG>). It will be understood that another number of clamping devices <NUM> can also be envisaged in accordance to the present invention. Top <NUM> of frame <NUM> is connected to base frame <NUM>, preferably with a number of bolts.

Clamping device <NUM> (<FIG>) comprises positioning drive <NUM> with cylinder <NUM> that is on one end <NUM> connected to second clamp body <NUM> with connection <NUM>. Clamping device <NUM> has similar components as shown in relation to the alternative clamping device <NUM>' (<FIG>). Cylinder <NUM> (<FIG>) enables movement in positioning direction A. This enables positioning clamping device <NUM> around a flange of a foundation element and thereafter (re)positioning second clamp body <NUM> relative to first clamp body <NUM> in positioning direction A.

In an illustrated alternative embodiment clamping device <NUM> (<FIG>) is used for vibrating or hammering device <NUM> comprising vibrator block <NUM> that is connected to base frame <NUM>. In the illustrated embodiment clamping device <NUM> preferably corresponds to clamping device <NUM>. Also in this illustrated embodiment vibrator block <NUM> is provided with hoist <NUM> to enable lifting and/or up-ending. Clamping device <NUM> is provided with frame <NUM>, first clamp body <NUM> and second clamp body <NUM>. In this embodiment clamping device <NUM> is fitted in recess <NUM> that is provided in carrier <NUM> of base frame <NUM>. Recess <NUM> is provided with maneuvering space A<NUM> that allows second clamp body <NUM> to move in direction A relative to first clamp body <NUM>.

In one of the presently preferred and illustrated embodiments clamping device <NUM>' is provided with slide elements <NUM> (<FIG>). In the illustrated embodiment slide elements <NUM> comprise slide recess 109a that is provided in frame <NUM> of clamping device <NUM> and sliding guide 109b that is provided in or on carrier <NUM>. It will be understood that other slide elements can also be configured according to the invention. First clamp body <NUM> is provided with two clamp pads <NUM>. It will be understood that another number of pads could also be envisaged according to the invention, such as one, three, four et cetera.

Clamping device <NUM>' (<FIG>) is provided with the same or similar components as illustrated in relation to clamping device <NUM>, <NUM>', <NUM> in relation to steering and controlling the movement of second clamp body <NUM> relative to first clamp body <NUM> in positioning direction A.

Clamping device <NUM>' (<FIG>) enables movement of clamp body <NUM> in direction A, A<NUM>. In the illustrated embodiment the interaction between clamp body <NUM> and slide elements <NUM>, 109a is configured to enable clamp body <NUM> to move towards clamp body <NUM> when initiating/starting the clamping action. In this illustrated embodiment the interaction is such that clamp body <NUM> makes a rotational movement X towards clamp body <NUM>. In this illustrated embodiment this is enabled by the interaction allowing no or minimal movement C<NUM> in direction Y (transversal to the plane of carrier <NUM> of base frame <NUM>) at or near end 116b of the moving clamp body <NUM>, while providing some play C<NUM> such that clamp body at clamping end 116a enables the aforementioned rotational movement in direction X. So, clamp body <NUM> is capable of translating in direction A for positioning and rotating in direction X for clamping a flange in direction Y. It will be understood that other configurations can also be envisaged in accordance with the invention.

Foundation element <NUM> (<FIG>, <FIG>) is provided with flange <NUM>. Clamping device <NUM>, <NUM>', <NUM>, <NUM>' is configured for clamping around flange <NUM> using first clamp body <NUM>, <NUM> and second clamp body <NUM>, <NUM>. In the illustrated embodiment clamping device <NUM>, <NUM>', <NUM>, <NUM>' is brought in opening <NUM> (see also figures 4C, <FIG>) at one end of foundation element <NUM>. Pile guide <NUM> (see also <FIG>, 4C, <FIG>) is provided to guide the positioning of clamping device <NUM>, <NUM>', <NUM>, <NUM>' relative to foundation element <NUM>. Pile guide <NUM> is optionally provided with one or more pile guide contact pads <NUM> to minimize the risk of damaging flange <NUM> and/or foundation element <NUM>.

In operation, pile guide <NUM> is arranged to frame <NUM>, <NUM> such that in a clamping state of clamping device <NUM>, <NUM>', <NUM>, <NUM>' clamp bodies <NUM>, <NUM>, <NUM>, <NUM> remain in engagement with respect of the flange surfaces. This provides additional safety. Optionally, pile guides <NUM> are part of pile guide web structure <NUM> (<FIG>) that adds to the overall stability and strength of frame <NUM>, <NUM>.

After being positioned inside opening <NUM> of foundation element <NUM> second clamp body <NUM>, <NUM> is moved in direction A relative to first clamping body <NUM>, <NUM> (<FIG>, <FIG>). In the illustrated embodiment this movement is achieved with cylinder <NUM>. Clamp bodies <NUM>, <NUM>, <NUM>, <NUM> are preferably provided with separate contact pads <NUM> (e.g. see <FIG>) that provide a contact surface between clamp bodies <NUM>, <NUM>, <NUM>, <NUM> and flange <NUM> of foundation element <NUM>. After the sliding movement in direction A, a clamping movement in clamping direction B with clamping drive <NUM> is provided. In the illustrated embodiment clamping direction B is substantially transversal to positioning direction A. In the illustrated embodiments clamping direction B corresponds to direction Y (<FIG>).

Clamping drive <NUM> is illustrated as a two-stage system (<FIG>). It will be understood that another configuration for clamping drive <NUM> can also be envisaged in accordance to the present invention. In the illustrated embodiment system <NUM> comprises first block <NUM>, second block <NUM>, clamp element <NUM> and optionally a number of contact pads <NUM>. Clamp element <NUM> is connected with bolts <NUM> to second block <NUM>. Guide block <NUM> is connected with bolts <NUM> to frame <NUM>, <NUM>. Clamping drive <NUM> with the two-stage system further comprises first chamber <NUM>, second chamber <NUM> and third chamber <NUM>.

In an open position of clamping device <NUM> (<FIG>) first element <NUM> and second element <NUM> move in opening direction C substantially parallel to clamping direction B. First and second chambers <NUM>, <NUM> are brought at a low pressure, and third chamber <NUM> is provided with a higher pressure to enable movement in direction C. In the illustrated embodiment the pressure in third chamber <NUM> can be about <NUM> bar in this stage of the operation.

In a closing position (<FIG>) first chamber <NUM> is brought at pressure, for example about <NUM> bar. Second and third chambers <NUM>, <NUM> are provided at low or zero pressure to enable movement of first element <NUM> and second element <NUM> in closing direction D. In the illustrated embodiment movement in direction D continues until first element <NUM>, <NUM> engages contact surface <NUM> of guiding element <NUM>. In this position clamping device <NUM>, <NUM> is closed.

To provide a clamping force on flange <NUM>, second chamber <NUM> is put under pressure, for example the same pressure of <NUM> bar. Pressurizing second chamber <NUM> enables movement of second element <NUM> in direction D parallel to clamping direction B.

It is noted that in the illustrated embodiment pressure is maintained in chambers <NUM>, <NUM>, <NUM> by providing a controlled return valve <NUM> controlled by control <NUM> (schematically illustrated in <FIG>). In this pre-tensioning stage foundation element <NUM> can be lifted and/or up-ended.

It will be understood that other working pressures can also be envisaged in accordance to the present invention, optionally including different pressures in different stages in the chambers of clamping device <NUM>, <NUM>.

Optionally, when in operation (e.g. see <FIG>), clamping forces can be reduced to improve the lifespan of flange <NUM> and/or foundation element <NUM>. This can be achieved by reducing pressure in second chamber <NUM>, for example to about <NUM> bar. It will be understood that another pressure can also be envisaged in accordance to the present invention. In this situation first chamber <NUM> is maintained at a relatively high pressure, for example <NUM> bar and third chamber <NUM> is maintained at a low pressure. Due to the external load when inserting foundation element <NUM> into the ground the actual operational pressure in second chamber <NUM> will vary in time, typically between <NUM> bar and <NUM> bar.

Optionally, inductive sensor <NUM> (<FIG>, <FIG>) is provided for positive confirmation of a retracted position of clamp bodies <NUM>, <NUM>, <NUM>, <NUM>. It will be understood that another sensor or combination of different sensors can also be envisaged in accordance to the present invention to the different embodiments of clamping device <NUM>, <NUM>.

A further optional feature is visual indicator <NUM> and/or another inductive sensor <NUM> (<FIG>) that are configured for confirmation that the sidewall of foundation element <NUM> is engaged. Optionally, clamping drive <NUM> is activated after positive feedback from one or more of the sensors (<FIG>). It will be understood that another sensor or combination of different sensors can also be envisaged in combination with drive <NUM>, <NUM> in accordance to the present invention in relation to the different embodiments of clamping device <NUM>, <NUM>', <NUM>, <NUM>'.

Also, base frame <NUM>, <NUM> is optionally provided with safeguarding elements <NUM> that maintain clamp bodies <NUM>, <NUM>, <NUM>, <NUM> in place in case of pressure loss (<FIG>). No pre-tension force for clamping force is lost.

Manifold <NUM> (<FIG>) is provided with balancing valves for positioning cylinder <NUM> to prevent overloading by any up-ending force and to hold clamp bodies <NUM>, <NUM>, <NUM>, <NUM> in the relative position even also in case of a pressure loss. Optionally, return valve <NUM> can be provided in manifold <NUM>. Also optionally, additional strain gauges and/or pressure sensors can be provided to monitor the clamping force, for example during operation such that controller <NUM> may adjust pressures in any of the chambers <NUM>, <NUM>, <NUM> and/or valves, such as return valve <NUM>. In the illustrated embodiments manifold <NUM> is also provided so-called flush valves to remove pressure and/or forces. It will be understood that manifold <NUM> can be applied to the different embodiments of clamping device <NUM>, <NUM>.

In one of the embodiments clamping device <NUM>' (<FIG>) is provided with additional wedge <NUM>. In this embodiment first chamber <NUM>' is put at the operating pressure. Wedge <NUM> is moved in direction E above cylinder with a slightly higher pressure such that wedge <NUM> transfers a relatively small force. During vibrating/hammering the pressures can be reduced as the pre-tension remains due to the mechanical securement of the wedge. When releasing clamp bodies <NUM>', <NUM>' from the flange first chamber <NUM>' and the pressure of wedge <NUM> are reduced such that the pre-tension on wedge <NUM> is reduced, thereby enabling a relatively easy removal of wedge <NUM>. Unlocking chamber <NUM> is put at pressure to enable retraction of the cylinder and opening of the clamping device <NUM>'.

Claim 1:
Clamping device (<NUM>, <NUM>', <NUM>, <NUM>') for a vibrating or hammering device (<NUM>, <NUM>) for inserting a foundation element (<NUM>) having a flange (<NUM>) into the ground, wherein the clamping device comprises:
- a frame (<NUM>, <NUM>);
- a first clamp body and a second clamp body (<NUM>, <NUM>, <NUM>, <NUM>) that are configured to enable a relative movement, and wherein the first and second clamp bodies are provided with respective first and second clamping surfaces that are configured for engaging with respective first and second flange surfaces;
- a positioning drive (<NUM>) configured for moving the first clamp body relative to the second clamp body in a positioning direction (A); and
- clamping drive (<NUM>) for moving the first clamp body relative to the second clamp body to and/or from the flange surfaces in a clamping direction B,
said clamping device being characterized in that it further comprises a pressure relief valve configured to prevent overloading in a driving state wherein the foundation element is inserted into the ground.