SU981883A1 - Multi-component eddy current converter - Google Patents

Description

(54) MULTIPLE-ELEMENTAL DIQUETRICAL CONVERTER

The invention relates to the non-destructive quality control of materials and products and can be used in all areas of the national economy.

A eddy current transducer with excitations and measuring windings is known, each of which is made in the form of two single-wire lines with alternating switching directions 1 ....

Closest to the invention is a multi-element eddy-current transducer for non-destructive testing, containing one axis-symmetric exciting and measuring windings one above the other, made each of an odd or odd number of single-wire lines, each having the same distance from one another and having alternating directions of connection. The windings are made with the same numbers. single wire scrap 2.

However, the well-known multi-element eddy current transducer does not provide high accuracy of control, for example, specific electric. 1WHEATABILITY of products due to the inconsistency of the phase of the output voltage of the converter from the gap changes.

The purpose of the invention is to improve the accuracy of control.

This goal is achieved in that in a multi-element eddy current transducer for non-destructive testing, containing one axis-symmetrical excitation and measuring windings one above the other, each made of an even or odd number of single-wire lines that are at the same distance from one another and having an alternating direction of inclusion single-wire lines in the windings are selected from a ratio of more than 1:10.

FIG. 1 shows the mutual position of the proposed multi-element eddy current transducer 1 and the product under test; in fig. 2 - dependences of the phase increment i (f of the output voltage on the total gap H 2 (h + for the known (a) and proposed (b) multi-element eddy current transducers for the generalized parameter

30 0

where d is the distance between the adjacent lines of each of the transducer windings; U is the frequency of the excitation current; e is the magnetic constant; (- specific electrical conductivity of the product.

Transducer 1 consists of two axisymmetric windings 2 and 3, located at a distance hg and hj from the surface of the tested product 4.: Each of the windings is made of single-wire lines 5 and 6 with alternating switching directions. The distances between adjacent winding lines 2 and adjacent winding lines 3 are the same and equal, d. Winding 2 and 3, respectively, contain (n, and mg of single-wire lines, and the number of single-wire lines (mj + m) is even.

In the process of testing, the winding lines 2 and 3 of the converter 1 are placed parallel to the surface of product 4. Since the lines of the Moryt multi-element converter to be fabricated on an elastic basis with galvanic Yutem, it is possible to control products with a curvilinear surface. The number of single-wire lines in the windings is selected from a correlation of more than 1:10.

FIG. 2 shows the dependence (B) (H) for the converter with the ratio of the number of single-wire lines 5 of winding 2 to the number of single-wire; water lines b winding 3 (m, j / mg) equal to 21 at p 2.5. Similar results also occur for other values of the parameter (3.

Unlike the similar dependence (a) for a known eddy current transducer with the ratio ni2 / mjl, the output voltage phase of the proposed multi-element eddy current transducer remains almost constant when the generalized gap varies widely, 4to allows you to measure, for example, the specific electrical conductivity of products by phase method with high accuracy,

The converter allows without

the use of additional devices, eliminating the phase failure of the output voltage of the converter from changing the gap, improve the accuracy of control of products with both flat and curvilinear surfaces when solving a number of important for the practice of non-destructive testing tasks.

Claims (2)

 1. Belikov E.G. Comparative analysis of linear and circular surface-mounted transducers, i., MEI, 1975, vol. 226, p. 5968. 2. Belikov E.G. The results of the study of the output characteristics of a linearly extended multi-element superimposed eddy current transducer. M., MEI, 1975, vol. 428, with. 56-60 (prototype).