ZWP Anlagenrevision GmbH • Südstraße 1 • 66701 Beckingen • Germany

Material Testing (NDT)

We’ve been providing our customers with competence and expertise for over 35 years.

No matter whether it comes to mechanical engineering, plant engineering, power plants or the maintenance of pipelines, reliability and safety must always be guaranteed.

Independent inspections can ensure that both legal obligations and your own high quality standards are met. Hidden defects can be detected at an early stage so as to prevent unexpected problems from occurring.

To do so, the following processes are used according to the material and problem at hand:

X-ray testing

Radiographic testing is an imaging method used to illustrate differences in material density. The density of the component is depicted on an X-ray film with the use of a suitable emitter (X-ray tube, isotope). The projection image will show up in different shades of black as a result of the varying density or thickness of the component. The denser or thicker a component is, the less radiation is able to penetrate it. This results in less blackening on the film. X-ray testing is mandatory in the case of welded joints on components with thin walls.

Ultrasonic testing

Ultrasonic testing is an acoustic method for detecting material defects. A transducer generates a sound impulse which is transmitted to the component via a coupling medium. The sound impulse is reflected through boundary surfaces in the test specimen that have different sound resistances (cracks, doublings, rear wall, etc.) and sent back to the transducer. This now works as the receiver. Based on the time between transmission and reception, the distance travelled is calculated (pulse-echo method). The ultrasonic testing method is particularly well suited for detecting surface flaws such as cracks or bonding defects.

Dye-penetrant technique

The dye-penetrant method is one of the oldest non-destructive test methods. It is used to determine surface defects. In this method, the test liquid penetrates into all of the surface defects on the material as a result of capillary action.
After carefully washing off the penetrant, a developer layer is applied which creates a counter-capillarity. This sucks out the liquid that has penetrated existing cavities and cracks and makes the defects visible. The dye-penetrant method is particularly suitable for detecting surface defects.

Magnetic particle testing

This method is only suitable for ferromagnetic materials. It is used to determine surface defects. The flux leakage caused by magnetization on surface cracks results in the magnetic particles in the test medium adhering.

Visual testing

Components or steel structures often first undergo a visual inspection by experienced testing staff. Any potential weak points are then also examined using non-destructive testing methods.

ZWP Anlagenrevision GmbH

 
ZWP Anlagenrevision GmbH
Südstraße 1
66701 Beckingen
 
Fon: +49 (0) 68 35 / 40 96
Fax: +49 (0) 68 35 / 6 88 11
E-Mail:  info@zwpar.de