Ultrasonic testing (UT)
We provide individual and serial ultrasonic testing of your components – manually, mechanized or automated.
2 ways to your inspection, you decide:
Non destructive testing with ultrasound (UT)
What is ultrasonic testing?
Materials conduct sound. Non-destructive testing makes use of this property for the detection and location of defects in materials. Here, the sound that is not audible to humans, the so-called ultrasound, is used in the frequency range of approx. 0.05 to 50 MHz.
How does the material testing using ultrasonic works?
Sound waves have the property that they are reflected at so-called interfaces. Interfaces can be transitions from one medium to another, e.g. from steel to air or from the base material to inclusions in the materials. These reflections are also picked up again by the ultrasonic testing system that emitted the sound wave and enable the detection and location of possible defects in the component.
The purer the medium, the easier it is to detect defects using ultrasonic testing. This is due to the fact that sound in purer media causes fewer reflections in the structure of the material at the grain boundaries and thus a lower so-called background noise.
A medium, usually water or gel, is required to couple the ultrasound to the component. The reason is the high acoustic impedance of air. Air directly at the transducer does not allow the ultrasound to pass. Therefore a coupling agent must be applied between the transducer and the material to be tested. An ultrasonic coupling gel, water, oil or paste is usually used for this purpose. Depending on how water-sensitive your component is and which access possibilities exist, we test using immersion technology, local immersion technology (bubbler technology) or contact technology.
When is ultrasonic testing applied ?
Material testing with ultrasound is used to detect defects near the surface as well as defects in the volume of materials.
Detectable defects are:
- Doubled slag lines
- Inhomogeneities and lack of bond
- Wall thickness variations
- Simple geometric surface
- Components made of
- Soundable materials (e.g. plastic or metal)
- Ideal for rotationally
- Symmetric components, plates, sheets and moulded parts
Minimal detectable defect:
- From approx. 0.05 mm defect expansion (high frequency testing)
- From approx. 0.2 mm defect expansion (conventional testing)
Detectable defect location:
- From approx. 0.5 mm below the surface (vertical test)
- From approx. 0.1 mm below the surface (angle check)
- Up to great depths of 10 m (as the sound path increases, the defect detectability becomes smaller and smaller due to the sound field opening and the diffusion in the structure)
Ultrasonic testing in our VOGT Test Center
Since 1983 we are the expert for ultrasonic testing. We perform single and serial tests of your (pre-)materials and components quickly and safely at your site or in our VOGT test centre.
We are an independent testing laboratory accredited to DIN EN ISO/IEC 17025, certified to ISO 9001 for industry and EN 9100 for aviation and have MTU and Rolls-Royce approval (1000 Gates).