An electrical arrangement for an electric arc furnace (1) operated with alternating current has a converter (2) which converts mains voltage (U), having a mains frequency (f), of a supply grid (3) into primary voltage (U) having a furnace frequency (f). A furnace transformer (4) of the electrical arrangement transforms the primary voltage (U) into a secondary voltage (U). The secondary voltage (U) is supplied to a number of electrodes (6) of the electric arc furnace (1). The electrodes (6) are arranged in a furnace vessel (8) of the electric arc furnace (1). They apply electric arcs (10) to a melt material (9) in the furnace vessel (8). The secondary voltage (U) is also supplied to a capacitor assembly (7) which is on the output side of the furnace transformer (4) and to which the furnace transformer (4) is connected on the output side. The converter (2) is controlled by a control device (5) such that a primary voltage (U) output from the converter (2) to the furnace transformer (4) has a furnace frequency (f) which is at least ten times the mains frequency (f) and/or is greater than 1 kHz.

This disclosure provides systems, methods, and apparatus related to deposition techniques using laser ablation. In one aspect, an optical fiber and target of a material to be deposited on a first region of an interior surface of a hollow component are positioned in the hollow component. A first end of the optical fiber is coupled to a laser system. A second end of the optical fiber is proximate the target. The material is deposited on the first region of the interior surface of the hollow component by directing a first laser pulse from the laser system through the optical fiber to impinge on the target.

The invention relates to a laser printing method that includes the following steps: (a) the provision of a receiver substrate (4); (b) the provision of a target substrate (5) comprising a transparent substrate (50) one surface of which has a coating has a coating (51) constituted of a solid metal film; (c) the localized irradiation of the said film (51) through the said transparent substrate (50) by means of a first laser (6) in order to reach the melting temperature of the metal in a target zone of the said film which is in liquid form; (d) the irradiation of the said liquid film through the said transparent substrate by means of a second laser on the said target zone defined in the step (c), in order to form a liquid jet in the said target zone and bring about the ejection thereof from the substrate in the form of molten metal; (e) the depositing on the receiver substrate of a molten metal drop over a defined receiving zone, with the said drop solidifying upon cooling.

Plant for melting metal materials comprising at least a heating unit (11) provided with a container (13) to contain the mainly metal materials and with at least an induction heating device (22) configured to heat the mainly metal materials contained in the container (13). The plant also comprises a transfer unit (25) disposed downstream of the heating unit (11) and configured to move, substantially continuously, the mainly metal solid materials exiting from the heating unit (11) to a melting furnace (12). The container (13) is provided with an aperture (16) through which the mainly metal material, heated and in a solid state, is discharged onto the transfer unit (25), and opening/closing members (17) are associated with the aperture (16), commanded by an actuator (19) and configured to open, close and choke the aperture (16) in order to regulate the delivery of the metal materials that is discharged onto the transfer unit (25).

Plant for melting metal materials comprising at least a heating unit (11) provided with a container (13) to contain the mainly metal materials and with at least an induction heating device (22) configured to heat the mainly metal materials contained in the container (13). The plant also comprises a transfer unit (25) disposed downstream of the heating unit (11) and configured to move, substantially continuously, the mainly metal solid materials exiting from the heating unit (11) to a melting furnace (12). The container (13) is provided with an aperture (16) through which the mainly metal material, heated and in a solid state, is discharged onto the transfer unit (25), and opening/closing members (17) are associated with the aperture (16), commanded by an actuator (19) and configured to open, close and choke the aperture (16) in order to regulate the delivery of the metal materials that is discharged onto the transfer unit (25).

Melting plant having a melting chamber which by way of a gas protection hood is separated from the environment, wherein the gas protection hood or another part of the melting chamber encasement has a lead through in which an electrode rod for moving an electrode to be melted is guided in a gas-tight manner by way of a sealing means. Hydraulic or pneumatic equalisation means, for exerting on the electrode rod equalisation forces which are in a proportional correlation with the gas pressure prevailing within the melting chamber are provided so as to compensate for the gas-pressure forces acting on the electrode rod.

Provided is an AC-DC-AC converter for delivering power to a load from a power source that includes a front-end converter, a load-end converter, and a DC link. The front-end converter being a hybrid modular multilevel rectifier, and the load-end converter being either a modular multilevel converter or a hybrid modular multilevel converter.

A method and device for laser-induced marking. The method comprises providing an article having a marking surface including a non-flat area, providing a first laser transfer foil, providing a first laser unit for emitting first laser light, providing a first hard adaptor that is essentially transparent to the first laser light, the first hard adaptor having a contacting surface that essentially is a negative of at least a part of the marking surface of the article, contacting the first laser transfer foil with the marking surface of the article by the first hard adaptor such that the first laser transfer foil is arranged between the marking surface of the article and the contacting surface of the first hard adaptor, and irradiating the first laser light through the first hard adaptor onto the first laser transfer foil. The device comprises a first laser unit for emitting and scanning first laser light over a first transfer area, a first foil unit for providing a first laser transfer foil at the first transfer area, a carrier for providing an article at the first transfer area, the article having a marking surface comprising a non-flat surface area, a first hard adaptor that is transparent for the first laser light, the first hard adapter having a first contacting surface that is essentially a negative of the non-flat surface area of the marking surface, and a contacting unit for bringing the first laser transfer foil in contact with the marking surface by causing the first contacting surface to move one of the first laser transfer foil and the marking surface towards one another.

In some aspects, a system for applying a fiber matrix on a tubular conduit is provided. The system can include a tubular conduit, a mandrel and a fiber matrix delivery assembly. The mandrel can comprise an elongate shaft and a rolling membrane configured to atraumatically engage the tubular conduit.

Plant for melting metal materials comprising at least a heating unit (11) provided with a container (13) to contain the mainly metal materials and with at least an induction heating device (22) configured to heat the mainly metal materials contained in the container (13). The plant also comprises a transfer unit (25) disposed downstream of the heating unit (11) and configured to move, substantially continuously, the mainly metal solid materials exiting from the heating unit (11) to a melting furnace (12). The container (13) is provided with an aperture (16) through which the mainly metal material, heated and in a solid state, is discharged onto the transfer unit (25), and opening/closing members (17) are associated with the aperture (16), commanded by an actuator (19) and configured to open, close and choke the aperture (16) in order to regulate the delivery of the metal materials that is discharged onto the transfer unit (25).