SU120357A1 - The method of determining the stress state of parts and structures made of isotropic materials without destroying them and an apparatus for carrying out the method - Google Patents

Description

First of all the invention is the icnocoo determination of the stress state of parts and structures made of isotropic materials, as well as a device for carrying out the proposed method.

Known methods for determining the stress of an island of parts, for example, from ferromagnetic materials, based on the use of directional electromagnetic oscillations and a differential electric circuit, require the use of complex magnetic devices and do not deflect the required efficiency of the determination of the stress state.

This nodO:: is eliminated in the described method and device by the fact that the distribution of stresses in the studied area of a part or structure is determined by the difference in the distribution of polarized electromagnetic oscillations in mutually perpendicular directions.

A device for carrying out a method, consisting of an is-t sensor with coils, included in the differential electric circuit and installed in the test area, with magnetic fields closed by a controlled part or structure, has the distinctive feature that the coil is radiating polarized electromagnetic oscillations located in the center seeker clamps. The receiving coils, which serve as the polarizer H of the analyzer, are located symmetrically with respect to the central coil but mutually perpendicular nloskos, the intersection lines of which coincide with the axis of the central coil.

FIG. 1 shows a device sensor finder in vertical section; in fig. 2 is the same in section along the line LL in FIG. one; in fig. 3- differential electrical circuit.

To establish the stress state at different points without destroying the part or construction of an isotropic material, the difference in the propagation of polarized electromagnetic oscillations in two mutually perpendicular planes is used. The source of electromagnetic oscillations is a central coil 1 seeker L 120357-2 -

sensor devices (Fig. 1-2). The receiving coils 2 and 3 of the device are located in a plane perpendicular to the plane of the receiving coils 4-5, and these planes intersect along the line of the axis of the coil /. A crosspiece 6 with cores 7 is fixed to the ends of the coils, and the position of the receiving coils is placed at equal distances from the axis of the coil; The sensor finder is enclosed in a holder 8.

The windings of the opposite coils 2-3 and 4-5 are connected in series so that the e. d. evolved. The two ends of the coil winding / and the four ends of the windings of coils 2-3 and 4-5 are brought out to the differential electrical circuit (Fig. 3), serving as the measuring part of the device.

To power the coil / alternator 9 with several fixed frequencies, assembled on crystal triodes. A compensator JO is included in the circuit between coil / and generator 9.

The four-pole switch // switches the ends of the windings of the pair of coils 2-3 with respect to the ends of the windings of the pair of coils -5; one position of the switch corresponds to the receipt of the voltage difference, the other - their sum. The currents are rectified by rectifier 12 and 13; the voltage difference is applied through potentiometer 14 to a zero current indicator 15, bridged through switch 16 with resistance 17.

When the device is far from the product, the zero position of the indicator 15 is characterized by means of a potentiometer 14. The device’s sensor-detector is applied to the surface of the part or structural element being monitored. Rotating the sensor-finder around the axis of the coil /, the direction and magnitude of the main stresses at each point on the surface of the investigated area are determined by the magnitude of the indicator deflection.

Subject invention

Claims (2)

1. A method for determining the stress state of parts and structures made of isotropic materials without their destruction, based on the use of directional electromagnetic oscillations and a differential electric circuit, characterized in that, in order to simplify and increase the efficiency of stress state determination, The area of the part or structure under investigation is determined from the difference in the propagation of polarized electromagnetic oscillations in mutually perpendicular directions. 2. A device for carrying out the method according to claim 1, consisting of a sensor-detector with coils installed in the differential circuit and installed on the test section, the magnetic fields of which are closed by a controlled part or structure, characterized in that, for the purpose of excitation in the test section and receiving polarized electromagnetic oscillations, emitting polarized electromagnetic oscillations, the coil is located in the center of the sensor finder sleeve, and the receiving coils serving as polarizer and an analyzer, disposed symmetrically relative to the central katuschki in mutually perpendicular planes the intersection line of which coincides with the central axis katuschki. Committee for Inventions and Discoveries at the Council of Ministers of the USSR Editor L. G. Golandsky. Gr. 172 Information and Publishing Department. Sub. to pec. 27.V-59 g. Volume 0.34 p. L. Zak. 3667 Circulation 1000. Price 50 kopecks. Printing house of the Committee on Inventions and Discoveries at the USSR Council of Ministers Moscow, Petrovka, 14.