Abstract: The invention relates to a method for connecting the ends of steel tubes by means of orbital welding using a hybrid laser arc technique, with the tubes preferably having wall thicknesses ?6 mm and more particularly ?12 mm and diameters of preferably ?150 mm, the ends of which tubes are connected by one or more welding passes, wherein the laser and arc welding heads as tools are guided over a guide ring fixedly arranged around a tube end in the region of the weld site during the welding and are displaced around the tube diameter. The invention also relates to a device for carrying out the method, wherein the laser and the arc welding heads are positioned separately on the guide ring and are moved over the tube circumference and controlled independently of one another during the welding process.

Abstract: A foundation structure of an offshore plant, such as a wind turbine, comprising at least one foundation element that can be anchored to the seabed without a gravity foundation and without a floating foundation and a support structure fastened thereto for fixing the offshore plant. The foundation element is a pile that can be inserted into the seabed by means of drilling and/or by means of vibratory driving, can be fixed in the seabed by means of an organic and/or inorganic material, and is oriented at an angle from a vertical on the seabed. A method of installing the foundation structure on a seabed includes first anchoring the coupling element by means of piles inserted into the seabed and then connecting the support structure to the coupling element.

Abstract: A foundation structure of an offshore plant, such as a wind turbine, comprising at least one foundation element that can be anchored to the seabed without a gravity foundation and without a floating foundation and a support structure fastened thereto for fixing the offshore plant. The foundation element is a pile that can be inserted into the seabed by means of drilling and/or by means of vibratory driving, can be fixed in the seabed by means of an organic and/or inorganic material, and is oriented at an angle from a vertical on the seabed. A method of installing the foundation structure on a seabed includes first anchoring the coupling element by means of piles inserted into the seabed and then connecting the support structure to the coupling element.

Abstract: The invention relates to a method for connecting the ends of steel tubes by means of orbital welding using a hybrid laser arc technique, with the tubes preferably having wall thicknesses ?6 mm and more particularly ?12 mm and diameters of preferably ?150 mm, the ends of which tubes are connected by one or more welding passes, wherein the laser and arc welding heads as tools are guided over a guide ring fixedly arranged around a tube end in the region of the weld site during the welding and are displaced around the tube diameter. The invention also relates to a device for carrying out the method, wherein the laser and the arc welding heads are positioned separately on the guide ring and are moved over the tube circumference and controlled independently of one another during the welding process.