Abstract: A pile driver provided with a housing and at least one body connected with the housing so as to be moved back and forth over a predetermined path, the pile driver being further provided with a drive for moving the body back and forth over the path for the purpose of pile-driving, the pile driver comprising at least two parts movable relative to each other, respectively having at least a first type of sliding surface and at least a second type of sliding surface which during pile-driving slide along each other and between which there is a lubricant, wherein the first type of sliding surface is provided with polyether ether ketone.

Abstract: An arrangement for installing building elements, such as piles and tunnel sections, into a ground formation, where a building element is provided. Two or more impact drivers for delivering blows to the element are mounted on or operatively connected to the element. Accordingly, large elements, such as monopiles for wind turbines, which may comprise a steel tube having a diameter in excess of 5 meters, or even tunnel sections, can be installed by utilizing a number of relatively small impact drivers.

Abstract: The invention pertains to a system (1) for installing foundation elements, such as piles or conductors (2), in a sub-sea ground formation (3), comprising a hydraulic driver (8) and a power converter (9) for generating hydraulic pressure in a hydraulic fluid for the driver (8). The driver (8) and the converter (9) are adapted to fit inside the foundation elements (2).

Abstract: A pile driver provided with a housing and at least one body connected with the housing so as to be movable back and forth over a predetermined path, the pile driver being further provided with a drive for moving the body back and forth over the path for the purpose of pile-driving, the pile driver comprising at least two parts movable relative to each other, respectively having at least a first type of sliding surface and at least a second type of sliding surface which during pile-driving slide along each other and between which there is a lubricant, wherein the first type of sliding surface is provided with polyether ether ketone.

Abstract: An arrangement for installing building elements, such as piles and tunnel sections, into a ground formation, which arrangement comprises such a building element is provided. Two or more impact drivers for delivering blows to the element are mounted on or operatively connected to the element. Accordingly, large elements, such as monopiles for wind turbines, which may comprise a steel tube having a diameter in excess of 5 meters, or even tunnel sections, can be installed by means of a number of relatively small impact drivers.