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TÜV AUSTRIA Websites > Stage GR > Solution > Ultrasonic testing – UT Solution: Ultrasonic testing – UT Δοκιμές & επιθεώρηση Solution: Ultrasonic testing – UT TPA KKS GMBH - TÜV AUSTRIA Group TPA KKS GMBH - TÜV AUSTRIA Group Region: Österreich Deutschstraße 10 1230 Wien Österreich +43 1 616 38 99 0 Send email Deutschstraße 10 1230 Wien Österreich Save to My Bundle TPA KKS GMBH - TÜV AUSTRIA Group Save to My Bundle Ultrasonic Testing - UT In which region do you need this solution? Austria Greece All accreditations Reflexionsschallverfahren und Durchschallungsverfahren Reflection sound method (also pulse-echo method). The smallest discontinuity that can be represented is greater than half the wavelength of the sound, which depends on the speed of sound of the material and the frequency of the probe. At a frequency of 4 MHz, this comes to about 0.7 mm in steel. The frequency cannot be increased indefinitely because the grain boundaries of the microstructure cause scattering and absorption, which reduces the penetration depth. The coarser the crystal formation in cast steel, for example, the longer wavelengths must be selected for the sound frequency. In the case of cast iron and austenite, testability is generally very limited. The largest material distances that are usually sonicated in the pulse echo method are 5 m, which corresponds to a sonic path of 10 m. "Ultrasonic testing (UT) is an acoustic method for finding material defects using ultrasound, allowing components to be inspected even when installed." Ultrasonic testing UT Ultrasonic testing is an acoustic method for finding material defects using ultrasound. It is one of the non-destructive testing methods. This allows components to be inspected even when installed. Application area Ultrasonic testing is a suitable testing method for materials capable of conducting sound (including most metals) for the detection of internal and external defects, e.g. in weld seams, forgings, castings, semi-finished products or pipes. The detection of external (surface) defects is particularly important for parts where the other, usually internal, surface is not accessible. UT Ultrasonic testing procedure Two basic methods are used: Reflection sound method (also pulse-echo method). The smallest discontinuity that can be represented is greater than half the wavelength of the sound, which depends on the speed of sound of the material and the frequency of the probe. At a frequency of 4 MHz, this comes to about 0.7 mm in steel. The frequency cannot be increased indefinitely because the grain boundaries of the microstructure cause scattering and absorption, which reduces the penetration depth. The coarser the crystal formation in cast steel, for example, the longer wavelengths must be selected for the sound frequency. In the case of cast iron and austenite, testability is generally very limited. The largest material distances that are usually sonicated in the pulse echo method are 5 m, which corresponds to a sonic path of 10 m. Impact echo method This method involves two probes connected to the same ultrasonic unit. One probe transmits the pulse and the other receives the pulse on the exact opposite side of the specimen. This method is very special and is mostly used for testing for doubling. In addition, very near-surface zones can be tested, as this is not possible with the reflection sound method due to a “dead zone”. The “dead zone” occurs because a probe cannot transmit and receive at the same time. Ultrasonic testing method In ultrasonic testing, a coupling agent (e.g. paste, gel, water or oil) is applied to the surface of the workpiece. By means of a probe, which emits and receives ultrasound from 0.02 to 50 MHz, the surface to be inspected is scanned. This can be done manually, mechanized or automatically (within the production lines). In the latter case, the test piece is often immersed in a suitable liquid (immersion technique) or wetted in a defined manner in order to transmit the sound signal. Changes in the acoustic properties at interfaces (e.g. a blowhole (cavity), inclusion, crack or other separation in the microstructure) inside the part under test reflect the acoustic pulse and send it back to the transducer in the probe, which acts as both transmitter and receiver. The elapsed time between transmission and reception allows the displacement to be calculated (pulse-echo method). Based on the measured time difference, a signal image is generated and visualized on a monitor. Based on this image, the position can be determined and the size of the discontinuity can be estimated by comparing it with a substitute reflector (flat-bottom bore (circular-disk reflector), groove, transverse bore). More Tags: Acoustic method Acoustics Circular disks Couplant Discontinuity Disk reflector Flat bottom hole Fluid Groove Immersion method Industry Material NDT Non-destructive testing (NDT)Querbohrung Reflection Reflektor Sound reflection method Spare reflector Surface Surfaces Through-transmission Through-transmission method Ultrasound UT Zerstörungsfreie Prüfung Related solutions from the same sector: Industry Magnetic particle testing – MT Show more Save to my Bundle Radiographic testing – RT Show more Save to my Bundle Penetrant testing – PT Show more Save to my Bundle Visual inspection VT Show more Save to my Bundle All Solutions Discover more sectors: Agriculture Automotive Certification Communications Technology Construction & Real Estate Electronics Energy Foodstuffs Health & Medicine IT & Security Leisure & Entertainment Machinery Municipalities Science & Research Sports & Fitness Sustainability Tourism Trade & Commerce Transport & Traffic TPA KKS GMBH - TÜV AUSTRIA Group +43 1 616 38 99 0 \| office@tpa-kks.at
TPA KKS GMBH - TÜV AUSTRIA Group +43 1 616 38 99 0 \| office@tpa-kks.at

TÜV AUSTRIA Websites > Stage GR > Solution > Ultrasonic testing – UT

Solution: Ultrasonic testing – UT

Δοκιμές & επιθεώρηση

TPA KKS GMBH - TÜV AUSTRIA Group

Region: Österreich

Deutschstraße 10 1230 Wien Österreich

+43 1 616 38 99 0

Send email

Ultrasonic Testing - UT

In which region do you need this solution?

Austria
Greece

Reflexionsschallverfahren und Durchschallungsverfahren

Reflection sound method (also pulse-echo method).

The smallest discontinuity that can be represented is greater than half the wavelength of the sound, which depends on the speed of sound of the material and the frequency of the probe. At a frequency of 4 MHz, this comes to about 0.7 mm in steel. The frequency cannot be increased indefinitely because the grain boundaries of the microstructure cause scattering and absorption, which reduces the penetration depth. The coarser the crystal formation in cast steel, for example, the longer wavelengths must be selected for the sound frequency. In the case of cast iron and austenite, testability is generally very limited. The largest material distances that are usually sonicated in the pulse echo method are 5 m, which corresponds to a sonic path of 10 m.

"Ultrasonic testing (UT) is an acoustic method for finding material defects using ultrasound, allowing components to be inspected even when installed."

Ultrasonic testing UT

Ultrasonic testing is an acoustic method for finding material defects using ultrasound. It is one of the non-destructive testing methods. This allows components to be inspected even when installed.

Application area

Ultrasonic testing is a suitable testing method for materials capable of conducting sound (including most metals) for the detection of internal and external defects, e.g. in weld seams, forgings, castings, semi-finished products or pipes. The detection of external (surface) defects is particularly important for parts where the other, usually internal, surface is not accessible.

UT Ultrasonic testing procedure

Two basic methods are used:

Reflection sound method (also pulse-echo method).

Impact echo method

This method involves two probes connected to the same ultrasonic unit. One probe transmits the pulse and the other receives the pulse on the exact opposite side of the specimen. This method is very special and is mostly used for testing for doubling. In addition, very near-surface zones can be tested, as this is not possible with the reflection sound method due to a “dead zone”. The “dead zone” occurs because a probe cannot transmit and receive at the same time.

Ultrasonic testing method

In ultrasonic testing, a coupling agent (e.g. paste, gel, water or oil) is applied to the surface of the workpiece. By means of a probe, which emits and receives ultrasound from 0.02 to 50 MHz, the surface to be inspected is scanned. This can be done manually, mechanized or automatically (within the production lines). In the latter case, the test piece is often immersed in a suitable liquid (immersion technique) or wetted in a defined manner in order to transmit the sound signal.

Changes in the acoustic properties at interfaces (e.g. a blowhole (cavity), inclusion, crack or other separation in the microstructure) inside the part under test reflect the acoustic pulse and send it back to the transducer in the probe, which acts as both transmitter and receiver. The elapsed time between transmission and reception allows the displacement to be calculated (pulse-echo method).

Based on the measured time difference, a signal image is generated and visualized on a monitor. Based on this image, the position can be determined and the size of the discontinuity can be estimated by comparing it with a substitute reflector (flat-bottom bore (circular-disk reflector), groove, transverse bore).