RU1783415C - Inclined converter of ultrasound flaw detector - Google Patents

Abstract

The invention can be used in ultrasonic testing of welded joints of metal structures. The purpose of the invention is to increase the reliability of ultrasonic testing by increasing the accuracy of determining the equivalent size of a defect. An increase in the accuracy of determining the equivalent size of a defect is ensured by the fact that the size of the piezoelectric element in the plane of incidence of the ultrasonic beam is determined from the condition ( cos fi I / ha: sin2 ft) where ai is the size of the piezoelectric element in the plane of incidence of the ultrasonic beam, and for is the size of the piezoelectric element in plane perpendicular to the plane of incidence of the ultrasound beam, / is the angle of the prism, ci is the velocity of the ultrasonic wave in the material of the prism, C2 is the speed of the ultrasonic wave in the material of the test object. (/) WITH

Description

The invention relates to the field of non-destructive testing and can be used in ultrasonic testing of products by echo-pulse flaw detectors.

A transducer for ultrasonic monitoring of metals is known, comprising a piezoelectric element mounted on a prism.

Closest to the proposed one is an inclined transducer of an ultrasonic flaw detector containing a prism and a piezoelectric element connected to it.

A disadvantage of the known inclined transducer, selected as a prototype, is the low reliability of the control results, due to the low accuracy of determining the equivalent defect size. This disadvantage is especially noticeable when standardizing the sensitivity of the echo signal from

lateral cylindrical drilling, the most technologically advanced in manufacturing.

The purpose of the invention is to increase the reliability of the results of ultrasonic testing by increasing the accuracy of determining the equivalent defect size.

The goal is achieved due to the fact that in an inclined transducer containing a prism and a connected piezoelectric element, the size of the piezoelectric element in the plane of incidence of the ultrasonic beam is chosen not only depending on its size in the plane perpendicular to the plane of incidence of the ultrasonic beam, but also depending on the speed ultrasonic waves in the material of the prism and in the material of the test object and the angle of the prism, from the condition:

Vj 00

with

B;

cl

81 82

Cos ft

At

, - "Sfh2 / ct

where ai is the size of the piezoelectric element in the plane of incidence of the ultrasonic beam,

32 - the size of the piezoelectric element in a plane perpendicular to the plane of incidence of the ultrasonic beam,

 prisms

C1 is the speed of the ultrasonic wave in the material of the prism,

C2 is the speed of the ultrasonic wave in the material of the test object.

The drawing shows an inclined transducer containing a prism 1 and a piezoelectric element 2 connected to it.

The converter operates as follows.

An electric probe pulse of a flaw detector (not shown) is supplied to the piezoelectric element 2 and converted into an acoustic one. As a result, in Gtrism 1, an ultrasonic wave propagates in the direction of the test object 3, which reaches the boundary with the test object 3 and is refracted into it. If there is a defect in the test object, the ultrasonic wave is partially reflected from it and returns to the inclined transducer. In this case, refraction to the prism 1 occurs and the wave reaches the piezoelectric element 2. The piezoelectric element 2 is transformed by it into an acoustic one. As a result, an ultrasonic wave propagates in the prism 1 in the direction of the test object 3, which reaches the boundary with the test object 3 and is refracted therein. If there is an ultrasonic defect in the test object, the wave is partially reflected from

and returns to the inclined transducer. In this case, refraction to the prism 1 and the wave reaches the piezoelectric element 2. The piezoelectric element 2 converts the acoustic echo signal into an electric one, the amplitude 11d of which is measured using an ultrasonic flaw detector. In a similar manner, the amplitude of the echo Do from the reference reflector is measured. After measurements, the amplitude ratio U / / U0 is found and the value of this ratio U (Ufl / Uo) determines the equivalent defect size Ze,

Claims (1)

The use of the invention improves the reliability of the control by providing a more accurate determination of the equivalent defect size. SUMMARY OF THE INVENTION An inclined transducer of an ultrasonic flaw detector comprising a prism and a piezoelectric element connected to it, characterized in that, in order to increase the reliability of the ultrasonic inspection results by increasing the accuracy of determining the equivalent defect size, the size ai of the piezoelectric element in the plane of incidence of the ultrasonic beam is determined from the condition ai 32 cos in 1 g with sln2yS where 32 is the size of the piezoelectric element in a plane perpendicular to the plane of the ultrasonic beam;  prism angle; ci is the velocity of the ultrasonic wave in the prism material; C2 is the speed of the ultrasonic wave in the material of the test object.