SU1296928A1 - Method of ultrasonic checking of welded joints - Google Patents

Abstract

The invention relates to the field of non-destructive agents and control methods and can be used in the ultrasonic testing of welded joints of cylindrical products. The aim of the invention is to increase the reliability of control by determining the shape of the defect. For implementing the method, an ultrasonic inclined transducer 1 is used, which is mounted on the product 2 with a welded seam 3. Shear waves are introduced into the product, the echo pulses are received by the flaw detector and the presence of defect 4 is determined. The distance L from the transducer to the defect is determined , L. Calculate the ratio -, where R K is the radius of the product, and then -, where h is the depth of the defect, calculate the input angle about and at this angle shear waves with vertical (SV) and horizon are inserted into the product flax (SH) polarization, take echo pulses reflected from a defect, measure their amplitudes and compare them. If the amplitudes of the SV waves are less than the amplitudes of the SH waves, then a plane defect occurs. If the amplitudes of the SV and UH waves are about the same, then a bulk defect is detected. 1 il. JХ Sfi (L

Description

The invention relates to non-destructive tools and methods of control and can be used in the ultrasonic testing of welded joints of spherical and cylindrical products.

The purpose of the invention is to increase the reliability of control by determining the shape of the defect.

The drawing shows the scheme of the real welded connection.

In the drawing marked ultrasonic inclined transducer 1 mounted on the product 2 with the weld 3. Position 4 indicates the defect.

15

method of ultrasonic counter-Yu case of detection of a bulk defect

these amplitudes will be almost the same and the difference between them will be significantly less than the specified value.

The deviation of flat defects from the radius of the product is determined by the difference between the calculated angle oi and the initial angle of entry.

Thus, the method of ultrasonic testing of welded joints allows determining the shape of defects and their orientation in the product, which makes it possible to significantly increase the reliability of control.

The ultrasound monitoring method is pulsed as follows.

A shear-wave pulses are introduced into the product 2 by an inclined ultrasonic transducer 1, echo pulses are received by a flaw detector (not shown), and the presence of a defect 4 is determined. The flaw detector depth gauge determines the distance L at converter 25 to defect 4, calculates the ratio L / R, where R is the radius of the product, and according to nomogram 1 m built for planar defects, the formula of the invention

The method of ultrasound testing of welded joints of products, which are located along the radius of the product, onpe-jo that is introduced into the product

the depth of the defect and the angle o are divided. derived from the following expression

0 iarcsin

h-l).

the presence and depth of the defect, about J5 H.a y u and with the fact that, with

tilt transducer shear wave pulses accept echo impulses whose parameters determine

tl and purpose

where h is the depth of the defect

Cg velocity of shear and longitudinal waves in the product, respectively.

At an angle J, ultrasonic waves with horizontal and vertical polarization are introduced into product 2, echo pulses reflected from defect 4 are reflected, amplitudes are measured and 45 amplitudes of echo pulses are compared for waves with

niva them. For this product at the estimated angle of entry ot for flat editors H, Kistutinets

Compiled by N. Slusarenko

Tehred L.Oleynik Proofreader S.Cherni

Order 771/46 Circulation 777 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, F - 35, Raushsk nab., 4/5

. Production and printing company, Uzhgorod, Projecto st., 4

A minimum defect is observed in the reflection coefficient (R) of the vertically polarized and maximum of the horizontal polarized waves. Therefore, in the case of a plane defect, the amplitude of the echo pulses of vertically polarized waves is less than the amplitude of the echo pulses horizontally polarized waves by 15-18 dB. AT

Claims (1)

Invention Formula The method of ultrasound testing of welded joints of products consists in the presence and depth of the defect, about 5 hours. 0 tilt transducer shear wave pulses receive echo pulses, the parameters of which determine tl and - goal To increase the control reliability by determining the type of defect, taking into account the depth of the defect and the radius of the product, the angle of input of polarization of shear waves is determined, shear pulses with horizontal and vertical polarization are introduced into the product, the amplitudes of echo pulses are measured and maximum type of defect is determined by horizontal and vertical polarization.