SU1458431A1 - Arrangement for electrochemical protection of metal objects from corrosion prompted by leak currents - Google Patents

Abstract

The invention relates to corrosion protection and can be used to protect equipment against corrosion in an electrolyte under the action of leakage currents in the electrochemical industries of various industries. The purpose of the invention is to increase the reliability of protection. The device contains electrodes — cathode 5 and anode 6, located at the ends of the object to be protected I, respectively, exposed to anode and cathode leakage currents, electrical insulation means 7.8 between the electrodes and the object; pins 11, 12 with electrodes, also located outside the electrolyte. The proposed device provides equipment protection against corrosion due to the fact that the electrodes and the conductor of the first kind provide for the drainage of corrosive currents from the protected object. 3 il. (L

Description

koprovod - conductor 10 of the first kind

located outside the electrolyte flowing through conduit 2 and {electrical contact contacts P and 12 with cathode 5 and anode 6, also located outside the electrolyte materials

have a low overvoltage, respectively, of cathode reduction and anodic oxidation on their surface of the solution components. For example, in acidic solutions of sodium chloride

five

From the conductor, the current flows to the anode 6, from where it flows into the electrolyte, which is expressed in the anodic oxidation of the components of the solution. The direction of current movement is indicated by arrows.

The main part of the current, or all of the current that, prior to the installation of the specified protective equipment, impacted the protected object 1, causing it to corrode, is thus diverted from the protected object into a side chain formed by the cathode, the anode and the conductor. This becomes possible due to the low overvoltage of the cathodic process of recovering the components of the solution at the cathode and the anodic oxidation of the components of the solution at the anode, the magnitude of this overvoltage, especially at the anode, VioryT being much lower than that of the protected object, as well as due to the larger shoulder between the cathode and the anode compared to the maximum linear size of the protected object along the external current lol. As a consequence, the magnitude of the potential drop in the electrolyte in the shoulder between the anode and cathode is greater than between the extreme points along the external current 1y on the protected object, which, all other things being equal, causes most of the current to fall on the protective equipment.

An increase in the cathode-anode shoulder can be achieved either by increasing the distance between them by lengthening the insulating inserts (isolation means) 7 and 8, or by orienting them along the external current field and ensuring their sufficient length. An example of the cathode and anode oriented along the field is given as a variant of the device in FIG. 2, where the electrodes are in the form of nozzles. The increase in the distance between the anode and the cathode with behind-; The shield of the flow meter float (Fig. 3) can be achieved by installing additional insulating inserts at the ends of the flow meter housing 13.

The efficiency of current diversion from the protected object is not determined by the size of the latter, since the shoulder between the cathode and the anode is always larger than the size of the object. In addition, the efficiency does not depend on the configuration of this object: since the current is diverted from the object to contact with it, the possibility of current shielding is excluded when any configuration of the details of the protected object is complicated.

Due to the absence of contact between the means of protection (the cathode and the anode) and the protected object behind

The shield becomes more reliable due to the absence of electrical contacts in the electrolyte. The contacts between the electrodes (anode and cathode) are located outside the electrolyte and are easily controlled. In this case, the magnitude of the external current flowing between the electrodes can be changed. p using a current-measuring device mounted on a current transducer (Fig. 1-3). Due to the absence of electrical contact of the protected object with protective equipment, contact corrosion of the protected object and protective equipment is prevented if this object contains parts from dissimilar materials. .

The device allows you to protect objects that do not allow electrical contact with protective equipment, and external current on the protected metal.

Thus, the proposed device, characterized by simplicity and ease of implementation, increases the reliability of protecting metal equipment and pipelines from corrosion under the influence of external current and expands the scope of application of protection of metal equipment and pipeline elements from corrosion.

Claims (1)

Invention Formula 30 35 50 40 A device for electrochemical protection of metal objects from corrosion in an electrolyte under the influence of leakage currents, containing an anode and a cathode electrically interconnected, and insulating elements, characterized in that, in order to increase the reliability of protection, the cathode is mounted at the input relative to the current pipe connected through an electrolyte to a metal object, and the anode - in the output, and the anode and cathode are isolated from the metal object, and the electrical connection is made from the outside vodov. l