# US 5,700,366 A · Electrolytic process for cleaning and coating electrically conducting surfaces > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,700,366 A - Document ID: US5700366A - Status: Granted - Kind: A - Application number: 08/706,914 - Filed: 1996-09-03 - Granted: 1997-12-23 - Earliest claimed: 1996-03-20 - Assignees: Metal Technology, Inc. - Inventors: Valerij Leontievich Steblianko; Vitalij Makrovich Riabkov - Web page: https://patentgrep.com/patent/US5700366A ## CPC - C25D 11/02: Anodisation - C25D 5/08: Electroplating with moving electrolyte e.g. jet electroplating {(using locally applied jets of electrolyte C25D5/026)} - C25D 5/611: {Smooth layers} - C25D 11/026: {Anodisation with spark discharge} - C25F 1/00: Electrolytic cleaning, degreasing, pickling or descaling - C25F 7/00: Constructional parts, or assemblies thereof, of cells for electrolytic removal of material from objects (for both electrolytic coating and removal C25D); Servicing or operating - C25D: PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR - C25F: PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR ## Abstract An electrolytic process for simultaneously cleaning and metal-coating the surface of a workpiece of an electrically conducting material, which process comprises: i) providing an electrolytic cell with a cathode comprising the surface of the workpiece and an anode comprising the metal for metal-coating of the surface of the workpiece; ii) introducing an electrolyte into the zone created between the anode and the cathode by causing it to flow under pressure through at least one opening in the anode and thereby impinge on the cathode; and iii) applying a voltage between the anode and the cathode and operating in a regime in which the electrical current decreases or remains substantially constant with increase in the voltage applied between the anode and the cathode, and in a regime in which discrete gas bubbles are present on the surface of the workpiece during treatment. ## Claims ### Claim 1 An electrolytic process for simultaneously cleaning and metal-coating the surface of a workpiece of an electrically conducting material, which process comprises: i) providing an electrolytic cell with a cathode comprising the surface of the workpiece and an anode comprising the metal for metal-coating of the surface of the workpiece; ii) introducing an electrolyte into the zone created between the anode and the cathode by causing it to flow under pressure through at least one opening in the anode and impinge on the cathode; and iii) applying a voltage between the anode and the cathode and operating in a regime in which the electrical current decreases or remains substantially constant with increase in the voltage applied between the anode and the cathode, and in a regime in which discrete gas bubbles are present on the surface of the workpiece during treatment. ### Claim 2 (depends on 1) A process as claimed in claim 1 wherein the workpiece has a surface which is selected from the group consisting of a single metal and an alloy of two or more metals. ### Claim 3 (depends on 2) A process as claimed in claim 2 wherein the material from which the anode is made is the same material as that of the surface of the workpiece. ### Claim 4 (depends on 2) A process as claimed in claim 2 wherein the material from which the anode is made is a different material from that of the surface of the workpiece. ### Claim 5 (depends on 1) A process as claimed in claim 1 wherein the anode is a composite structure assembled from more than one material selected from the group consisting of single metals and alloys. ### Claim 6 (depends on 1) A process as claimed in claim 1 wherein the anode is formed from a material selected from the group consisting of wire mesh, expanded metal and porous metal. ### Claim 7 (depends on 1) A process as claimed in claim 1 in which the surface of the workpiece is not immersed in the electrolyte. ### Claim 8 A process as claimed in claim i wherein the anode has a plurality of openings which extend through the anode to a working face thereof. ### Claim 9 (depends on 8) A process as claimed in claim 8 wherein said openings comprise holes. ### Claim 10 (depends on 8) A process as claimed in claim 8 wherein said openings comprise channels. ### Claim 11 (depends on 8) A process as claimed in claim 8 wherein said openings comprise apertures. ### Claim 12 (depends on 1) A process as claimed in claim 1 wherein the electrolyte flows under pressure through the anode as a plurality of jets and wherein an electrically insulated screen is positioned in the electrolytic cell adjacent the anode in order to refine the jets of electrolyte emerging from the anode into finer jets which impinge upon the cathode. ### Claim 13 (depends on 1) A process as claimed in claim 1 wherein the surface of the workpiece is immersed in the electrolyte. ### Claim 14 (depends on 1) A process as claimed in claim 1 wherein the electrolyte contains at least one water-soluble ionisable compound of the metal which is to be coated onto the surface of the workpiece. ### Claim 15 (depends on 1) A process as claimed in claim 1 wherein a plurality of anodes are used. ### Claim 16 (depends on 15) A process as claimed in claim 15 wherein said workpiece has opposing sides and at least one anode is disposed on one side of a workpiece to be treated and at least one anode is disposed on the opposite side of the workpiece to be treated, whereby the opposite sides of the said workpiece are simultaneously cleaned and coated. ### Claim 17 (depends on 16) A process as claimed in claim 16 wherein the workpiece is in a form selected from the group consisting of a metal strip, a metal sheet and a metal slab. ### Claim 18 (depends on 16) A process as claimed in claim 16 wherein the opposite sides of the workpiece are coated with different metal coatings. ### Claim 19 (depends on 16) A process as claimed in claim 16 wherein the opposite sides of the workpiece are coated with metal coatings of different thicknesses. ### Claim 20 (depends on 1) A process as claimed in claim 1 wherein the workpiece is a pipe. ### Claim 21 (depends on 1) A process as claimed in claim 1 wherein the workpiece is made from stainless steel. ### Claim 22 (depends on 1) A process as claimed in claim 1 wherein the surface of the workpiece moves relative to the anode during the treatment. ### Claim 23 (depends on 1) A process as claimed in claim 1 wherein the anode comprises an electrically-conducting material.