A method of forming a curved-shaped processing hole in a workpiece by electromechanical machining includes a step of feeding an electrolytic solution through an inner channel of a processing electrode and jetting the electrolytic solution from an outlet opening of the inner channel disposed on a tip surface of the processing electrode, a step of applying a potential difference between the processing electrode and the workpiece while jetting the electrolytic solution from the outlet opening of the processing electrode, and a step of forming the curved-shaped processing hole in the workpiece. In the jetting step, at least one of a current density distribution on the tip surface of the processing electrode or a flow velocity distribution of the electrolytic solution jetted from the outlet opening is eccentric to a downstream side of a curving direction of the processing hole with respect to an axial center of the tip surface.

A method of forming a curved-shaped processing hole in a workpiece by electromechanical machining includes a step of feeding an electrolytic solution through an inner channel of a processing electrode and jetting the electrolytic solution from an outlet opening of the inner channel disposed on a tip surface of the processing electrode, a step of applying a potential difference between the processing electrode and the workpiece while jetting the electrolytic solution from the outlet opening of the processing electrode, and a step of forming the curved-shaped processing hole in the workpiece. In the jetting step, at least one of a current density distribution on the tip surface of the processing electrode or a flow velocity distribution of the electrolytic solution jetted from the outlet opening is eccentric to a downstream side of a curving direction of the processing hole with respect to an axial center of the tip surface.

Tooling for producing scallops and fastening holes of a clamp of a disc by electrochemical machining using an electrolyte, the tooling having: an annular support tray to receive the disc; lower and upper shields configured to protect the disc from splashes of the electrolyte; a clamping lock to hold the disc in position during machining; and a die-sinking tool having in a substantially cylindrical insulating body a first and a second coaxial conductive cathode, the first and second cathodes rigidly fastened to each other, the first annular cathode including at an external periphery a plurality of radial machining protrusions of a shape complementary to that of the scallops to be machined and the second cathode includes, on the same circumference external to the first cathode relative to the central axis of the disc, a plurality of axial machining nozzles of a shape similar to the fastening holes to be machined.

Tooling for producing scallops and fastening holes of a clamp of a disc by electrochemical machining using an electrolyte, the tooling having: an annular support tray to receive the disc; lower and upper shields configured to protect the disc from splashes of the electrolyte; a clamping lock to hold the disc in position during machining; and a die-sinking tool having in a substantially cylindrical insulating body a first and a second coaxial conductive cathode, the first and second cathodes rigidly fastened to each other, the first annular cathode including at an external periphery a plurality of radial machining protrusions of a shape complementary to that of the scallops to be machined and the second cathode includes, on the same circumference external to the first cathode relative to the central axis of the disc, a plurality of axial machining nozzles of a shape similar to the fastening holes to be machined.

The invention relates to a method for removing Cr(VI) ions from an aqueous electrolyte solution, particularly an electrolyte solution for electrochemical metal machining, which comprises the reduction of Cr(VI) to Cr(III) with Fe(II) ions. The Fe(II) ions are added to the electrolyte solution in the form of an aqueous salt solution which has been brought into contact with an ion exchange resin loaded with Fe(II) ions. The invention further relates to a device (1) for electrochemical machining of a workpiece (2) by means of an aqueous electrolyte solution (6), which has an ion exchanger (11) which has been loaded with an ion exchange resin charged with Fe(II) ions.

The invention relates to a method for removing Cr(VI) ions from an aqueous electrolyte solution, particularly an electrolyte solution for electrochemical metal machining, which comprises the reduction of Cr(VI) to Cr(III) with Fe(II) ions. The Fe(II) ions are added to the electrolyte solution in the form of an aqueous salt solution which has been brought into contact with an ion exchange resin loaded with Fe(II) ions. The invention further relates to a device (1) for electrochemical machining of a workpiece (2) by means of an aqueous electrolyte solution (6), which has an ion exchanger (11) which has been loaded with an ion exchange resin charged with Fe(II) ions.

Tooling for producing scallops and fastening holes of a clamp of a disc by electrochemical machining using an electrolyte, the tooling having: an annular support tray to receive the disc; lower and upper shields configured to protect the disc from splashes of the electrolyte; a clamping lock to hold the disc in position during machining; and a die-sinking tool having in a substantially cylindrical insulating body a first and a second coaxial conductive cathode, the first and second cathodes rigidly fastened to each other, the first annular cathode including at an external periphery a plurality of radial machining protrusions of a shape complementary to that of the scallops to be machined and the second cathode includes, on the same circumference external to the first cathode relative to the central axis of the disc, a plurality of axial machining nozzles of a shape similar to the fastening holes to be machined.

Tooling for producing scallops and fastening holes of a clamp of a disc by electrochemical machining using an electrolyte, the tooling having: an annular support tray to receive the disc; lower and upper shields configured to protect the disc from splashes of the electrolyte; a clamping lock to hold the disc in position during machining; and a die-sinking tool having in a substantially cylindrical insulating body a first and a second coaxial conductive cathode, the first and second cathodes rigidly fastened to each other, the first annular cathode including at an external periphery a plurality of radial machining protrusions of a shape complementary to that of the scallops to be machined and the second cathode includes, on the same circumference external to the first cathode relative to the central axis of the disc, a plurality of axial machining nozzles of a shape similar to the fastening holes to be machined.

Electric discharge electrodes are disposed at equal intervals along a circumference about a rotary shaft, and provided so as to be capable of being brought into and out of contact with vanes such that one electric discharge electrode corresponds to one vane. The electric discharge electrodes each have an electrode surface along a surface to be machined of a corresponding one of the vanes. After the electric discharge electrodes each move radially inward toward the rotary shaft, the rotary shaft rotates and electrochemical machining is thus performed while the electrode surface and the surface to be machined are close to and thus face each other.

Electric discharge electrodes are disposed at equal intervals along a circumference about a rotary shaft, and provided so as to be capable of being brought into and out of contact with vanes such that one electric discharge electrode corresponds to one vane. The electric discharge electrodes each have an electrode surface along a surface to be machined of a corresponding one of the vanes. After the electric discharge electrodes each move radially inward toward the rotary shaft, the rotary shaft rotates and electrochemical machining is thus performed while the electrode surface and the surface to be machined are close to and thus face each other.