SU1221591A1 - Method of ultrasonic immersion converter alignment - Google Patents

Abstract

The invention relates to non-destructive testing and can be used for ultrasonic (US) immersion flaw detection using transducers mounted obliquely relative to the product being monitored. The aim of the invention is to simplify the setting and increase its accuracy due to its implementation with the normal incidence of ultrasonic vibrations on the surface of the test item. Before tuning, set between the transducer 1 immersed in the immersion liquid 3 and the inclined prism 2 with an angle controlled by the product 4 (the slope selected from the ratio tf arctg (sin oL -), where C C, cosoi-C / C, about - the angle of incidence of the longitudinal ultrasonic wave on the surface of the monitored product 4, the velocity of propagation of the longitudinal ultrasonic wave in the immersion liquid 3J, the velocity of propagation of the longitudinal ultrasonic wave in the material of the prism 2. They emit transducer 1 and receive ultrasonic pulses reflected from the surface of the tested product 4, measure the number of reflections of the maximum amplitude. Change the orientation of transducer 1 with prism 2 relative to the surface of the monitored product 4 until the maximum of the measured parameter is obtained and remove the prism 2 after fixing the position of transducer 1. 1il, (/) (С (С | U1; about UCH: U

Description

one

The invention relates to non-destructive testing and can be used in ultrasonic immersion inspection of products using transducers mounted obliquely relative to the product being monitored.

The purpose of the invention is to simplify the tuning and increase its accuracy by performing tuning operations with an inclined prism installed between the transducer and the tuning object, the angle of inclination tf of which is chosen taking into account the propagation speeds of the longitudinal ultrasonic wave in the prism material and the immersion width, resulting in a normal incidence ultrasonic vibrations on the surface of the controlled product.

The drawing shows the propagation scheme of ultrasonic vibrations during tuning and testing.

In the drawing there are: 1 - a direct transducer, 2 - an inclined prism, 3 - an immersion liquid, 4 - a controlled item.

The method of tuning the ultrasonic immersion transducer is as follows.

Before tuning between the converter and the object of adjustment, which is used as a controlled product, an inclined prism with an angle of inclination cj is selected from the ratio

CF arctg (sinci

-)

cosot,

where ot is the angle of incidence of the longitudinal ultrasonic wave on the surface of the monitored product in the course of control, deg;

Sd is the velocity of propagation of a longitudinal ultrasonic wave in an immersion liquid, m / s,

 the propagation velocity of the longitudinal ultrasonic wave in the prism material, m / s.

Ultrasound pulses are emitted and received. The parameters of received pulses are measured, in which quality the number of reflections of maximum amplitude is used. Change the orientation of the transducer with a prism from 2191

relative to the surface of the target the surface of the monitored product, to obtain the maximum of the measured parameter. Lock the transducer in this position and remove the prism.

The method of tuning the ultrasonic immersive converter is implemented as follows.

 Before tuning, between the forward transducer 1, immersed in the immersion liquid 3, and the product under test 4, an inclined prism 2 is installed with an angle of inclination cp. The angle

tS tilt prism 2 is chosen from the ratio. Sheni

Cf arctg (

sinci

-)

cosoc-C / C,

where is oi. the angle of incidence of the longitudinal ultrasonic wave on the surface of the test product 4,. m / s.

Cjj - propagation velocity

longitudinal ultrasonic wave in an immersion liquid 3, M / S, C, is the velocity of propagation

longitudinal ultrasonic wave in the material of the prism 2,

m / s

So, for example, when monitoring a steel product 4 (C 3200 m / s) at an angle oi of the fall of the longitudinal ultrasonic wave on the surface of the controlled product 4, equal to oi 21, which ensures the propagation of transverse ultrasonic vibrations in the controlled product 4 in the middle part of the range of angles, limited to the first and second critical angles, using water (C 1500 m / s) as the immersion liquid 3, and organic glass (C, 2700 m / s) as the material of the prism 2 is Cf 43 30. Converter 1 rad chaet ultrasonic pulses which are incident on the face of the prism 2 at an angle are refracted at an angle to it and. propagating further in the immersion liquid 2, they fall on the surface of the inspected product 4. Accept ultrasonic pulses reflected from the surface of the inspected product 4, and the number of reflections is measured using a flaw detector (not shown). Change orientation

J1

transducer 1 with prism 2 relative to the surface of the product under test 4. When the measured parameter reaches its maximum, which occurs when the ultrasound 2 refracted by the prism 2 normally oscillates on the surface of the product under test 4, transducer 1 is fixed in this position. After that, the prism 2 is removed and the ultrasonic vibrations emitted by the transducer 1 fall onto the surface of the test article 4 at an angle oo, which is necessary during the test.

The proposed method of setting up an ultrasonic immersion transducer allows setting up controls for various sizes and configurations without using them specifically made for each size and configuration of test specimen items, since the transducer tuning is performed by reflecting the signal from the surface of the real product received for inspection.

Claims (1)

Invention Formula The method of tuning the ultrasonic immersion transducer, which consists in placing the transducer in front of the setup object, radiates and receives ultrasonic pulses, measures the parameters of the received pulses, changes the orientation of the transducer relative to Compiled by V. Gondarevsky Editor M. Dylyn Tehred V. Kadar Corrector V. But ha Order 1607/51 Circulation 778 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Branch ShSh Patent j Uzhgorod, st. Project, 4 91 object to a maximum of the measured parameter and fix it in this position, characterized in that, in order to simplify the adjustment and increase its accuracy, the monitored product is used as the object of tuning, and as the measured parameters - the number of reflections of maximum amplitude , install an inclined prism with a tilt angle qj before setting between the converter and the object of adjustment, change the orientation of the converter with a prism relative to the surface of the tested product to the floor the maximum number of reflections and remove the prism after fixing the position of the transducer, and the angle is chosen from the ratio sinct  s cos: -c./c; where r is the angle of incidence of the longitudinal ultrasonic wave on the surface of the controlled product in the process of control, deg; propagation velocity of the longitudinal ultrasonic wave in the immersion liquid, m / s; propagation velocity of the longitudinal ultrasonic wave in the prism material, m / s. С „С,