SU818208A1 - Device for electrochemical polishing of external surface of long articles - Google Patents

Abstract

1. A DEVICE FOR ELECTROCHEMICAL POLISHING OUTSIDE SURFACE OF LONG-DIMENSIONAL PRODUCTS, comprising a cathode chamber with a cylindrical perforated cathode, input and output damper chambers with hollow cuffs, characterized in that they use an appendant to be in an appendant to the w / w to put on an appendant to the w / w, with an arsenic to get ready to go to the front. the cathode and the inner surface of the anodic chamber, and at the end of the cathode grooves are made, separating diaphragm is installed at the anodic and cathodic chambers s and torets the seal at the outlet of the anode chamber is located in the same plane as the edge Ka. then yes. , • 2. The device according to p. 1, about t l and - the fact that the grooves at the entrance to the anode zone are located tangentially to the inner surface of the cathode. 3. Device ppp. 1 and 2, characterized in that, in order to increase reliability, the cuffs are made of an anti-friction elastomer, and perforated sleeves are mounted in the annular chambers of the cuffs.

Description

. The invention relates to the field of electrolytic treatment of metals and can be used for continuous electrochemical polishing of the outer surface of long products made of zirconium alloys, especially shells for heat dissipating elements of atomic reactors, which must have high corrosion resistance. reactor coolant, for example, in water or steam-water mixture at a temperature of 300 ° C. A device for electrochemical polishing of the outer surface of long products is known, in which polishing is carried out on a small part with the continuous movement of products. In this device, the supply of current to the workpiece is realized by means of a sliding contact. In this case, sparking is possible in the contact zone, up to the formation of an arc. The surface of the products in this case becomes unusable. A bipolar electrolyzer for electrochemical polishing of the outer surface of pipes is known. The electrolyzer consists of cylindrical cathode and anode chambers separated by an electrically insulating sleeve with holes, which is simultaneously the diaphragm separating the electrolyte in the chambers. The electrolyte is fed from below into the anode chamber, a part of it is drawn out through the upper nozzle, and a part passes through the gap between the diaphragm and the tube into the cathode chamber and is brought out of it through the upper nozzle. Electric lysee is sealed on both sides with rubber cuffs. This cell design cannot be used for electrochemical polishing of the outer surface of articles. The purpose of the invention is to increase the quality of the treated surface. The goal is achieved by the fact that in a device for electrochemical polishing of the outer surface of long-dimensional products containing a cathode chamber with a Hz lindrical anode, an anode chamber with a cylindrical perforated cathode, and an input and output damper chambers in the anode chamber are made of a preliminary chamber formed by the outer surface of the cathode. and the inner surface of the anode chamber, and for introducing electrolyte into the anode zone at the end of the cathode, grooves are made that are tangential to the inner circumference of the cathode, which matured provide helical turbulent electrolyte movement. A separating diaphragm is installed to eliminate the short fluid communication between the anode and cathode chambers. To increase the reliability of the sealing cuffs, perforated sleeves are inserted into the annular chambers of the latter, and the cuffs themselves are made of an elastomer to prevent rubbing the surface. The formation of a gas cushion in the reaction zone and changes in the hydrodynamic flow conditions at the electrolyte outlet are prevented by the design of the anode chamber, which, in addition to the electrolyte injection chamber, consists of a working section of the chamber, a buffer section adjacent to the working section, and an auxiliary chamber, the upper part of which em the role of the gas collector. FIG. 1 shows a general view of the proposed device, a section; in fig. 2 is a section A-A of FIG. 1 The device has an anode chamber consisting of a working section 1 bounded by the inner surface of the cathode 2, a pre-chamber 3, bounded by the inner surface of the housing 4 and an end face of the housing 5 of the exit chamber 6, an auxiliary chamber 7 bounded by the inner surface of the anode chamber 8, outer the surface of the perforated cathode 2 and the end surface of the connecting sleeve 9, the buffer section 10, adjacent to the working section 1 and the auxiliary chamber 7, bounded by the inner surface the housing of the buffer section 11 and the end surface of the connecting sleeve 9. The anode chamber is adjacent to the cathode chamber consisting of a working section 12 bounded by the inner surface of the anode 13, the input buffer section 14 placed in the housing 11 of the buffer section of the anode chamber, the output buffer section 15 located in the housing of the entrance chamber 16. The housing of the chamber 16 and the rim 17 are formed by the inlet chamber 18, and by the housing 5 and the lid 17 - the exit chamber 6 .. Separating and sealing the chambers of the device along the surface This product 19 is manufactured using sealing cuffs 20, which are inserted into the sockets of the housing J, 11, 16 and the lids 17 of the chambers. The sealing cuffs form annular chambers 21 into which perforated sleeves 22 are inserted. The sealing of the cuffs is carried out using a pressure flange 23 and a perforated sleeve 22. The sealing of the device assemblies at the joints is performed using rubber gaskets. The device works as follows. The power supply from the power source is carried out directly to the 13 and to the housing 4 of the pre-chamber, which has a hard electrical connection to the cathode 2. The compressed air is supplied to the annular chambers 21 of the sealing cuffs 20 by sealing the chambers of the devices along the surface of the workpiece 19, which moves through the device with the help of rollers 24, with the direct current source turned on. At the same time, the electrolyte from the tank 25 is pumped through the cooler 27 into the preliminary chamber p and the buffer inlet section 14 of the cathode chamber through pump 26. From the pre-chamber 3, the electrolyte through the system of grooves 28 enters the working area 40

the anode chamber 1, while the flow of electrolyte is associated with a turbulent helical motion. From the working section, the electrolyte enters the buffer section 10 of the anode chamber, from which 45 is produced the output of the electrolyte. The resulting gases pass through the holes of the perforated cathode 2 and are collected in the upper hour of the metal, 10-50 microns in diameter. The pressure of compressed air in the annular chambers of the sealing cuffs is set at 2-4 atm.

The use of this invention makes it possible to obtain a surface of purity class 9-12 compared to a purity class of 7.8 with chemical etching carried out for the same purpose. 08 4 auxiliary chambers 7, from where they enter the buffer section of the anode chamber 7 through the holes in the connecting sleeve 9 and are led out together with the electrolyte through the piping system into the tank 25. The electrolyte from the input buffer section 14 passes through the cathode working section 12 and chamber 16 enters the tank 25 for the electrolyte. Simultaneously with the supply of electrolyte through the inlet chamber 18 and the outlet chamber 6 in a closed circular system from the tank 29, the pump 30 circulates the organic liquid (dimethylformamide), which prepares the surface of the workpiece for polishing and pre-rinsing the polished surface from the electrolyte. In the course of operation, the product leaving the area is connected with a subsequent special sleeve of conductive material. At the polishing ends, after the last work piece in the device, a similar construction piece is inserted, which remains in the device until it starts working again. The optimal hydrodynamic flow rate of the electrolyte, characterized by the Reynolds criterion, is 15,000 - 25,000. The speed of movement of products during polishing is 0.5 - 3 m / min, the current is 100 - 300 A, the voltage is 50 - 150 V. The temperature in the process the work is kept under 15 -. Removal amount

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818208

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Claims (3)

1. DEVICE FOR ELECTROCHEMICAL POLISHING OF EXTERNAL SURFACE OF LONG-DIMENSIONAL PRODUCTS, comprising a cathode chamber with a cylindrical perforated cathode, input and output damping chambers with hollow ring cuffs, characterized in that, in order to improve the quality of processing, the anode chamber has a pre-formed chamber surface of the cathode and the inner surface of the anode chamber, and grooves are made at the end of the cathode, separation diaphragms are installed between the anode and cathode chambers GMs and end face of the seal at the outlet of the anode chamber is located in the same plane as the cathode edge. , 2. The device according to claim 1, characterized in that the grooves at the entrance to the anode zone are tangent to the inner surface of the cathode. 3. The device popp. 1 and 2, characterized in that, in order to increase the reliability of the cuff, they are made of antifriction elastomer, and perforated bushings are mounted in the annular chambers of the cuffs. ., SU-818208