SU1640629A1 - Method of verification of relative position of transducers in a block upon automatic testing - Google Patents

Abstract

The invention relates to non-destructive testing of materials and can be used in the calibration of a multichannel flaw detector before testing products. The purpose of the invention is to improve the accuracy and performance of calibration. With automated control, two oppositely directed transducer block movements are carried out at a constant speed over a standard with a slotted flat-bottomed reflector. During the movement, the coordinates of the block are determined at the moment when each transducer intersects the reference slot. This makes it possible to calculate the mutual spatial displacement of the transducers in the block, eliminating the influence of the deviation of the slit direction from the block strictly perpendicular to the direction of movement of the block to the calibration result, which eliminates the need for time-consuming alignment of the standard before calibration. 2 Il. J

Description

The invention relates to non-destructive testing of materials and can be used when adjusting the deflector before the inspection of products.

The purpose of the invention is to improve the accuracy and performance of calibration.

FIG. 1 shows a scheme for checking the relative position of the transducers in the unit; in fig. 2 is a diagram for determining the distance between the transducers in the block in vertical section.

Block 1 of transducers 2 is moved over reference 3, having a flat-bottom slot 4 with a plane of symmetry 5. 6 and 7 are the lines along which transducer block 1 is moved relative to reference 3.

The method is implemented as follows.

Unit 1 of transducers 2 is moved at a constant speed along line 6

above the standard 3, made in the form of a rectangular sample with a flat-bottomed slit 4 in its lower part. The reference is set so that the plane of symmetry of the slot 5 is perpendicular to the direction of radiation of transducers 2. Transducers 2 emit pulses of ultrasonic vibrations in the direction of reference 3 Accept by transducers 2 echo signals from reference 3 and determine the coordinates of each transducer 2 at the time it crosses the flat-bottomed slot 4. Then the transducer block 1 is moved along line 7 parallel to the line 6 of the first movement of transducer block 1 in the direction opposite to the first move, and are the coordinates of each of the inverter 2 at the time of crossing flat-bottomed slot 4. Then the determined spatial displacement between jnj-1 transducers of conditions

ABOUT

N o o; u o

OH

Jj-1

- ± x, 1-1 NT I

N A Fii "i

xx

HB-HA

h -ryl fr OHj-l).

where xji and are the coordinates of the J and j-1 transducers, respectively, when receiving the 1st echo signal during the second pass of the block above the standard perpendicular to the plane of symmetry of the slot;

x d, y AG of the coordinates of the first transform at the first pass of the block above the standard at the moment of crossing the gap;

х Б-Б Б- coordinates of the first converter at the second pass of the block above the standard at the moment of crossing the slot;

Jj and Ij-i are the distance along the slit from the first converter to the Jth and j-1th converters, respectively;

N and N are the number of echo signals received by the jth and jth 1 transducers, respectively.

The mutual spatial displacement between and j-1 transducers is calculated according to the indicated formula, which allows to correct the effect of slot inclination and eliminate the operation of setting the reference so that the slot is perpendicular to the direction of movement of the transducer block. The time required for the block to move along the slit direction and for the second movement over the standard turns out to be much less than the time required in the known method for setting the standard.

The accuracy of verification is enhanced by eliminating the standard setting operation perpendicular to the direction of movement of the transducer block, which is an additional source of error.

In the formula for determining the displacement between j and j-1 converters, the physical meaning

HB-HA. (, | h

 lrj -f)

the term is an amendment that takes into account the effect of the angle of inclination of the slit to the Y axis on the measurement result.

The number of echoes N, received by adjacent transducers can be different for the following reasons: the spread of the transducer parameters (beam width, conversion factor), the settings of the receiving device channels to which the transducers are connected. That is why to determine the x0 coordinate

five

0

five

0

five

0

the static axis of the j-ro converter introduces 1 with the factor g; physically he means

N1

that the x coordinate of the acoustic axis of the transducer is taken as the arithmetic average of the x coordinate x j of the transducer measured at the moments when the transducer receives echo signals from the slot reflector.

Claims (1)

Claims The method of checking the mutual arrangement of converters in a block with automated control includes moving the block of converters with a constant speed over a standard made in the form of a rectangular sample with a flat-bottom slit in its lower part, set so that the plane of slit symmetry is perpendicular to the direction transducer radiation, each transducer emit pulses of ultrasonic oscillations in the direction of the reference, receive echo signals from the reference transducer, about The coordinates of each transducer are limited at the moment when it crosses the flat-bottom slot of the reference, characterized in that, in order to improve the accuracy and performance of the calibration, the transducer block is further moved over the reference along a line parallel to the first movement of the transducer block over the reference, in the direction opposite to the first displacement, the coordinates of each transducer are determined at the moment of intersection of the flat-bottom slot of the standard and the spatial displacement between} and j -1 is determined ate conditions of E  x m - 1  V Nj, Ј | five 0 five xxC + (iHj-i) where x | and x are the coordinates of the j and j-1 transducers, respectively, when the fth echo signal is received during the second pass of the block above the standard perpendicular to the plane of symmetry of the slit; x d, y A - coordinates of the first transducer during the first pass of the block over the standard at the moment of crossing the slot; B. U B - the coordinates of the first converter at the second pass of the block over the template at the moment of crossing the slot; Ij, Ij-i is the distance along the slit from the first converter to J and j-1 converter, respectively; N, N is the number of echo signals received respectively by the j-1 converter, .Ј FIG. one E I) DN J-f