Abstract: A seat structure includes a frame having a plurality of parts having respective joining surfaces. Two respective joining surfaces, which belong to two respective different parts, are joined to one another by laser-welding. A method of forming a seat frame having a plurality of parts includes the steps of positioning the parts in a fixture, fixing the position of the parts relative to one another and laser-welding the parts to form the seat frame.

Abstract: A structure includes a first part provided in a first plane and second and third parts provided in a second plane located under the first plane. The second and third parts are welded together at a welded seam. The first part has at least one recess configured to receive a welding mechanism that forms the welded seam on the second and third parts. Another structure includes an “n” number of layers, n being at least three. Adjacent layers are in contact with one another and are connected by a welded seam. The structure also includes an outer surface. The layers between the outer surface and the respective welded seam define a recess through which a welding mechanism is configured to be passed as far as the respective layers to be welded to produce the welded seam.

Abstract: A method of joining at least one first metal sheet and a second metal sheet by laser welding includes at least partially stacking the at least one first metal sheet and the second metal sheet on top of one another to form an overlap region and welding together the at least one first metal sheet and the second metal sheet in the overlap region along an oscillating line. Welding along an oscillating line creates a longer weld seam in comparison to welding along a straight line, thereby increasing the strength of the weld seam.

Abstract: A structure includes a first part provided in a first plane and second and third parts provided in a second plane located under the first plane. The second and third parts are welded together at a welded seam. The first part has at least one recess configured to receive a welding mechanism that forms the welded seam on the second and third parts. Another structure includes an “n” number of layers, n being at least three. Adjacent layers are in contact with one another and are connected by a welded seam. The structure also includes an outer surface. The layers between the outer surface and the respective welded seam define a recess through which a welding mechanism is configured to be passed as far as the respective layers to be welded to produce the welded seam.

Abstract: A seat structure includes a frame having a plurality of parts having respective joining surfaces. Two respective joining surfaces, which belong to two respective different parts, are joined to one another by laser-welding. A method of forming a seat frame having a plurality of parts includes the steps of positioning the parts in a fixture, fixing the position of the parts relative to one another and laser-welding the parts to form the seat frame.

Abstract: A liquid distributor, for a substantially vertical reactor with a fixed bed catalyst, in the form of a channel distributor with drainage outlets and further comprising an internal cleaning mechanism with cleaning elements to be lowered into the openings of the drainage outlets, is disclosed.