RU1822498C - Device to protect current-carrying surface of object from atmospheric corrosion - Google Patents

Abstract

The invention relates to instrumentation and can be used to determine the presence, measure the duration and reduce the impact of precipitation on various metal surfaces. The inventive device contains 1 oscillator (1), 1 voltage transducer (2), 1 threshold switching circuit (3), 2 indication elements (4, 6), 1 short circuit protection circuit (5), n protective electrodes (7), n reference electrodes (8) and 1 reference circuit (9). 1-2-3-5-7, 8-9-2. 3-1. 5-1. 3-4, 5-6. 1 s P. f-ly, 2 ill.

Description

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The invention relates to instrumentation and can be used to determine the presence, measure the duration and reduce the impact of precipitation on various metal surfaces.

The drawing shows a block diagram of a device.

The device comprises an oscillation generator 1, a voltage converter 2, a switch-on circuit of the device 3, an operation indicator of the device 4, a short-circuit protection circuit 5, a short-circuit indicator 6 and a reference potential block including protective electrodes 7, comparison electrodes 8 and comparison chart 9.

The device operates as follows.

Preliminarily, protective electrodes 7 and reference electrodes 8, electrically isolated from the protected surface, are installed on the surface to be protected and electrically connected according to the block diagram shown in the drawing. -

Then, the required voltage is supplied to the power terminals. If there is an electrical connection between the protective electrodes 7 and the surface to be protected through an electrolyte, the switching circuit of the device 3 generates a start signal for the generator 1 and turns on the operation indicator of the device 4, The electrical signal from the oscillation generator 1 is fed to the input of the voltage transducer 2, for which a constant voltage of the required polarity and magnitude is formed at the output, depending on the method being implemented — cathodic or anodic protection. The output voltage of voltage converter 2 is changed in accordance with the control signal coming from comparison circuit 9 connected to reference electrodes 8. The output signal of voltage converter 2 through the switching circuit of device 3 and short-circuit protection circuit 4 is applied to protective electrodes 7.

When the conductivity between the protective electrodes 7 and the protected surface decreases, the switching circuit 3 turns off the protection device and switches to standby mode, while the current consumption does not exceed 0.1 mA.

If during the installation of the protective electrodes 7, as well as during operation, a short circuit occurs between the protective electrodes 7 and the surface to be protected (which excludes normal

operation of the device), then a short circuit protection circuit 5 generates signals that turn off the oscillation generator 1 (this in turn reduces the short circuit current) and turn on the short circuit indicator 6. After eliminating the short circuit, the device fully regains its functionality.

In the case of cathodic protection of steel structures, this device can function even without the introduction of reference electrodes 8 and reference circuit 9. In this mode of operation, the device automatically maintains the potential of the surface to be protected in the range from -0.55 to -0.8 V. As the studies showed in this range of potential values, both through and uniform corrosion are almost completely suppressed. An increase in the potential of the protected metal of less than 0.8 V is impractical, since this does not further reduce the corrosion rate, but causes a rapid evolution of hydrogen, which can cause peeling of the protective non-metallic coatings on the steel surface.

The minimum protective current density, which depends on the material being studied / type of ions, electrolyte concentration, fluid mobility, should lead to the establishment of an appropriate protective potential. With anode protection, such a potential is the value of the passivation potential.

Claims (1)

1. A device for protecting the conductive surface of an object from atmospheric corrosion, comprising a voltage transducer connected to protective electrodes adapted to be insulated on the surface to be protected, wherein the first input of the voltage transducer is configured to be connected to one of the poles of the voltage source a wiring connected by the other pole to the surface to be protected, characterized in that it is provided with an oscillation generator, the input of which is configured to be connected to the voltage source, and the output is connected to the second input of the voltage converter, connected to the protective electrodes through the input and series-connected threshold circuit and short-circuit protection circuit, each of which is made with an indication element and connected to the corresponding input oscillation generator. 5 18224986 2, The device according to claim 1., distinguishing-output - with a control input prerelease in that it is equipped with voltage equalizing electrodes, while the knee generator is made with the possibility of oscillations and the voltage converter lined fixing on the protected are made with the possibility of connecting surface, and a comparison circuit, the input to the 5th negative pole of the source is connected to the reference electrodes rather than to the electrode.