The present disclosure provides downhole tools, methods for three dimensional printing hardfacing on such downhole tools, and systems for implementing such methods.

A control system for regulating an additive manufacturing process of an additive manufacturing apparatus, the apparatus configured to add metal to a substrate by means of metal deposition. The apparatus comprises: a nozzle for output of a metal strip, the nozzle configured to be arranged at a distance from the substrate, and configured to move relative the substrate in XYZ-axes via a position actuator. The apparatus further comprises a heat source configured to melt the metal strip into a weld pool on the substrate, and an electrical power source configured to supply current via the metal strip 20 to the substrate. The control system is configured maintain process stability, during the deposition of a layer of metal, via: determining electrical conductance between the metal strip and the substrate by measuring at least one electrical property of the supplied current; determining the difference between the determined electrical conductance, and a desired electrical conductance; and, adjusting at least one of: the substrate to nozzle distance, the speed of the nozzle movement relative the substrate, the amount of supplied current, the heat provided by the heat source, and/or the rate of output of the metal strip, based on the difference between the determined conductance and the desired conductance.

A control system for regulating an additive manufacturing process of an additive manufacturing apparatus, the apparatus configured to add metal to a substrate by means of metal deposition. The apparatus comprises: a nozzle for output of a metal strip, the nozzle configured to be arranged at a distance from the substrate, and configured to move relative the substrate in XYZ-axes via a position actuator. The apparatus further comprises a heat source configured to melt the metal strip into a weld pool on the substrate, and an electrical power source configured to supply current via the metal strip 20 to the substrate. The control system is configured maintain process stability, during the deposition of a layer of metal, via: determining electrical conductance between the metal strip and the substrate by measuring at least one electrical property of the supplied current; determining the difference between the determined electrical conductance, and a desired electrical conductance; and, adjusting at least one of: the substrate to nozzle distance, the speed of the nozzle movement relative the substrate, the amount of supplied current, the heat provided by the heat source, and/or the rate of output of the metal strip, based on the difference between the determined conductance and the desired conductance.

A high strength and corrosion resistant ferrochrome alloy bulk is disclosed, which comprises, in weight percent: 30-68% Cr, 1.5-8% Ni, 1.6-6% C, and the balance Fe and incidental impurities, of which a Fe/Ni ratio is in a range from 5 to 10 and a Cr/C ratio is in a range between 10 and 33. Experimental data reveal that, samples of the high strength and corrosion resistant ferrochrome alloy bulk all possess hardness above HV400 and excellent corrosion resistance due to the high content of Cr. As a result, experimental data have proved that the high-strength and corrosion-resistant ferrochrome alloy bulk of the present invention has a significant potential to replace conventional high-strength stainless steels, so as to be widely applied in various industrial fields, e.g., aviation, transportation, marine facility components, chemical equipment and pipe fittings, engine parts, turbine blades, valves, bearings, building materials, and so on.

The invention relates to a method for repairing a damaged blade tip of a turbine blade which is armor-plated and provided with a blade coating, of a thermal gas turbine. The method according to the invention comprises the steps of removing a blade tip armor plating of the turbine blade at least in the region of the damaged blade tip and producing a repair surface (12), removing only a part of the blade coating of the turbine blade in the region of the repair surface while preserving a part of the blade coating separated from the repair surface (14), restoring the blade tip reinforcement (20), and restoring the blade coating in the region of the repaired blade tip (22). The invention furthermore relates to a device for carrying out such a method.

The invention relates to a method for repairing a damaged blade tip of a turbine blade which is armor-plated and provided with a blade coating, of a thermal gas turbine. The method according to the invention comprises the steps of removing a blade tip armor plating of the turbine blade at least in the region of the damaged blade tip and producing a repair surface (12), removing only a part of the blade coating of the turbine blade in the region of the repair surface while preserving a part of the blade coating separated from the repair surface (14), restoring the blade tip reinforcement (20), and restoring the blade coating in the region of the repaired blade tip (22). The invention furthermore relates to a device for carrying out such a method.

An upstream rail of a turbine engine turbine casing, which includes a casing body extending along a longitudinal axis, includes a base including a radial face, extending substantially radially from the casing body, a plate including an upper face, extending substantially along the longitudinal axis, a connection portion between the base and the plate, including a concave face connecting the radial and upper faces, the concave and radial faces extending on either side of an edge. The upstream rail is repaired through a method including covering a surface with a solder, the surface including the upper and concave faces such that the solder extends until the edge, and machining the covered surface, in a single action, in a direction toward the radial face, so as to reshape the surface, wherein the machining of the covered surface is performed on a portion of the radial face.

A welding system includes a welding power supply, wire feeder, and welding circuit connecting the power supply to the wire feeder. The power supply and the wire feeder are configured for bidirectional communication over the welding circuit. The power supply includes a voltage sensor that measures a voltage level, and a current sensor that measures a current level, on the welding circuit. The power supply is configured to operate in a first welding mode to output a power voltage level to the welding circuit to power the wire feeder in response to a communication from the wire feeder over the welding circuit. The power supply generates periodic voltage dip pulses on the welding circuit, and automatically switches to a second welding mode different from the first welding mode based on the voltage level on the welding circuit falling below a threshold voltage level during a voltage dip pulse.

A steel track chain component, such as a track bushing, may be formed with a carburized portion, a hardface portion, and a core portion. The core portion may be softer than the carburized portion, which in turn, may be softer than the hardface portion. This configuration of the various portions of the component may allow for relatively high wear resistance of the component, as well as toughness. The core portion may be mostly ferrite crystal structure, while the carburized portion and the hardface portions may include martensitic and/or austenitic crystal structure. The carburized portion may be formed by carburizing the track chain component in a heated and carbon rich environment. The hardface portion may be formed by welding a hardface alloy over at least a portion of the carburized portion.

A steel track chain component, such as a track bushing, may be formed with a carburized portion, a hardface portion, and a core portion. The core portion may be softer than the carburized portion, which in turn, may be softer than the hardface portion. This configuration of the various portions of the component may allow for relatively high wear resistance of the component, as well as toughness. The core portion may be mostly ferrite crystal structure, while the carburized portion and the hardface portions may include martensitic and/or austenitic crystal structure. The carburized portion may be formed by carburizing the track chain component in a heated and carbon rich environment. The hardface portion may be formed by welding a hardface alloy over at least a portion of the carburized portion.