A spark erosion tool includes an electrode arranged on a tool longitudinal axis and an electrode holder aligned along and arranged on the axis and connected to the electrode. The electrode holder includes a moving device for moving the electrode relative to the electrode holder and includes a press for applying pressure transversely to the axis in the area of an imaginary hose extending in the axis. The electrode holder has a cross section corresponding essentially to the electrode. An electrode for a spark erosion tool with a cylinder surface or a spherical surface includes a groove connected to a bore. A deflecting bore can be produced in a drill string part using the spark erosion tool. The deflecting bore is curved and connects two straight flushing bores.

The present invention provides a wire electrode supply apparatus for suppressing wire electrode driving vibration for wire electrodes having a wide range of diameters and formed of various materials, thereby improving processed surface roughness. The wire electrode supply apparatus includes a back tension adjustment unit that adjusts a back tension of the wire electrode drawn from a source bobbin, a tension applying unit, and a constant pressure ejecting unit that ejects the wire electrode with constant pressure and rate after the transference via the tension applying unit and an electrical discharge machining unit. The tension applying unit includes a low tension applying unit that applies a tension to the wire electrode, and a high tension applying unit that can supply a higher tension. After the high tension applying unit supplies a tension, the low tension applying unit supplies a tension. Otherwise, only the low tension applying unit supplies a tension.

A tool electrode for an EDM system for repairing a micromixer tube of a combustor, the EDM system and a related method, are provided. The tool electrode includes an elongated member; and a disk having a first side, a second side, an opening in a center thereof, and a slot extending from the first side to the second side and from the opening to an outer periphery of the disk. The elongated member is coupled to the disk and extends through the opening from the first side of the disk and beyond the second side of the disk. The disk is used to remove a damaged end portion of a micromixer tube from within the tube, and without debris damaging the tube or a cutting tool damaging other tubes in a set of micromixer tubes.

A tool electrode for an EDM system for repairing a micromixer tube of a combustor, the EDM system and a related method, are provided. The tool electrode includes an elongated member; and a disk having a first side, a second side, an opening in a center thereof, and a slot extending from the first side to the second side and from the opening to an outer periphery of the disk. The elongated member is coupled to the disk and extends through the opening from the first side of the disk and beyond the second side of the disk. The disk is used to remove a damaged end portion of a micromixer tube from within the tube, and without debris damaging the tube or a cutting tool damaging other tubes in a set of micromixer tubes.

The micro-electric discharge milling machine includes a base having an X-axis guide plate mounted thereon, allowing for movement in the X-direction. A Y-axis guide plate is mounted on the X-axis guide plate, allowing for movement in the Y-direction. A dielectric bin is located on the Y-axis guide plate and is movable in the X-direction and the Y-direction via the X-axis guide plate and Y-axis guide plate, respectively. A workpiece platform is located within the dielectric bin for securing a workpiece. A vertical plate with a Z-axis guide plate extends from the base. A drill chuck is mounted on the Z-axis guide plate for securing a rotating electrode. A spark control circuit controls a location of a spark generated by the rotating electrode with respect to a surface of the rotating electrode.

The micro-electric discharge milling machine includes a base having an X-axis guide plate mounted thereon, allowing for movement in the X-direction. A Y-axis guide plate is mounted on the X-axis guide plate, allowing for movement in the Y-direction. A dielectric bin is located on the Y-axis guide plate and is movable in the X-direction and the Y-direction via the X-axis guide plate and Y-axis guide plate, respectively. A workpiece platform is located within the dielectric bin for securing a workpiece. A vertical plate with a Z-axis guide plate extends from the base. A drill chuck is mounted on the Z-axis guide plate for securing a rotating electrode. A spark control circuit controls a location of a spark generated by the rotating electrode with respect to a surface of the rotating electrode.