SU1002949A1 - Lengthy electroconductive article non-destruction checking device - Google Patents

Description

(AOR DEVICE FOR NON-DESTRUCTIVE TESTING

EXTENDED ELECTRIC CONDUCTING PRODUCTS

one

The invention relates to instrumentation technology and coins to be used for non-destructive testing of electrically conductive extended objects.

A device for non-destructive testing of extensive electrically conductive products is known, comprising a generator, means for transferring generator energy to a controlled product, a ferromagnetic bracket with a window sufficient to accommodate a section of the product, a second ferromagnetic bracket made with the possibility of turning (the common axis of the latter, connected measuring transducer installed between ferromagnetic brackets, signal processing unit and information representation unit l.

However, the device is not reliable enough, which is associated with a small gradient of redistribution of current density in the high frequency range.

The closest to the invention to the technical essence is a device for non-destructive testing of wired electrically conductive products, comprising an AC source, means for transferring the source energy to a controlled product for driving longitudinal currents in it, connected in series from, Q measuring transducers, signal processing unit and an information presentation unit, and a means for concentrating the current in the product 2.

However, this device does not have

, 5 the necessary reliability of control, which is connected with the insufficient redistribution of the current density by means of a means for concentrating the current in the product, made in the form of a ferromagnetic

20 staples.

The purpose of the invention is to increase reliability, control.

The goal is achieved by the fact that in the device for non-destructive

controlling extended electrically conductive products comprising an alternating current source, a means for transmitting the source energy to the monitored product for driving longitudinal currents therein, a measuring transducer unit connected in series, a signal processing unit and an information presenting unit, and means for concentrating the current density in the product, the latter is made in the form of a cylinder with a cavity; along the profile of the controlled product, the cylinder is composed of alternating nonmagnetic electrically conducting and dielectric f rromagnitnyh segments and transducers are placed on the inner surface of the cylinder beneath the electrically conductive segments. Fig, 1 shows a diagram of the proposed device; in fig. 2 section A-A in FIG. T. The device consists of an alternating current source 1, a means 2 for transmitting the energy of the source to a controlled product 3 "means for concentrating the current density in the product, consisting of a hollow cylinder with a cavity, along the profile of the controlled product 3 composed of alternating non-magnetic electrically conductive segments 5 and dielectric ferromagnetic segments 6, connected in series to transducer block 7, signal processing unit 8 and information representation unit 9. The measuring transducers are placed on the inner surface of the cylinder k under non-magnetic electrically conductive segments 5 The means 2 transferring the energy of the source to the monitored product can transfer energy galvanically, using a system of sliding contacts, or inductively, by transforming the energy into an electrically closed circuit that includes a controlled product, or through capacitive coupling.

The device works as follows.

An alternating current source 1 through a means 2 for transmitting the energy of the source to a controlled product excites in the extended product to be controlled 3 longitudinal alternating currents that form a circular magnetic field around the product 3. The magnetic field, interacting with the product being monitored, 3, distributes the current density, since the different layers of the product are not uniformly coupled with the magnetic flux. In this case, the density of currents is concentrated along the parameter of the product 3, both in the controlled and uncontrolled areas of it at the moment. This leads to an increase in noise and a decrease in the level of the useful signal.

The current density can be redistributed as desired by changing the configuration of the magnetic field so that the alternating magnetic flux is maximally coupled with controlled

The means for concentrating the current density 8 of the monitored product is performed so that the electrically conductive segments 5 are placed over the controlled areas of the latter, and the dielectric ferromagnetic segments 6 above the uncontrolled ones are measured by the magnetic field associated with the parameters of the monitored sections of the product placed plots, and the flux linkage with controlled plots is minimal. Then the induced current, which is the opposite, according to Lenz's law, in the direction of the current creating the magnetic flux, will redistribute the current density, increasing it in the controlled zone and decreasing it in the uncontrolled one. In order to distribute the alternating magnetic flux, it is necessary to appropriately change the magnetic resistance over the surface of the product 3. To do this, the controlled product 3 is introduced into the cavity of the cylinder k. the effective redistribution of the magnetic flux in the low-frequency region of a change in the magnetic flux, however insufficient in the high-frequency region. This disadvantage is eliminated by the operation of electrically conductive segments 5 placed between dielectric ferromagnetic segments 6. In the high frequencies, segments 5 represent a greater magnetic resistance for a variable magnetic flux, which allows the necessary redistribution of the magnetic flux to be maintained when the frequency of the latter varies widely.

over the inner surface of the cylinder under its electrically conductive segments 5. During the testing process, the product 3 moves progressively and rotates around the axis of the cylinder k, which allows the BCW surface of the product to be consistently monitored. It is also possible to place several qi, linders t with a given coal offset between them relative to each other, which eliminates the need to rotate the product. The signals from the measuring transducer block 7 are fed to the input of the signal processing block 8, & then to block 9 of the information representation, according to the state of which the parameters of the controlled product are determined

The device is non-destructive (the whole control provides the necessary gradient of current density, concentrated on the controlled areas of the product in a wide range of operating frequencies and allows to increase the signal-to-noise ratio, and, consequently, increases the reliability of the control.

The invention is a device for non-destructive testing of wired electrically conducting products containing an alternating current source, means for transferring the source energy to a controlled product for exciting longitudinal currents in it, a transducer unit connected in series, a signal processing unit and a presentation unit, and means for concentrating current density in the product, characterized in that, in order to increase the control level, the means for concentrating the current density in the product is discharged. Neno as a cylinder with a cavity on pro / "article of controlled, the cylinder is made of alternating conductive and non-magnetic dielectric ferromagnetic segments and transducers are placed on the inner surface of the cylinder beneath the electrically conductive segments.

Sources of information taken into account in the examination

t. USSR author's certificate tf 938122, cl. G 01 N 27/90, 1980.

2. USSR author's certificate “903757, cl. G 01 N 27/90, 1980 (prototype).

Claims (1)

claims A device for non-destructive testing of extended electrically conductive products, comprising an alternating current source, means for transmitting the source energy into the controlled object for excitation of longitudinal currents therein, connected in series by the measuring transducers unit, the signal processing unit and the information presentation unit, and the means for concentrating the current density in the product, characterized in that, in order to increase the reliability of control, a means for concentration of current density in the product is made in the form of a cylinder with a cavity, along the profile of the controlled product, the cylinder is composed of alternating non-magnetic electrically conductive and dielectric ferromagnetic segments, and measuring transducers are placed on the inner surface of the cylinder under the electrically conductive segments.