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A-NDT services

A-NDT services

Nondestructive testing (NDT) is the process of inspecting, testing, or evaluating materials, components or assemblies for discontinuities, or differences in characteristics without destroying the serviceability of the part or system. In other words, when the inspection or test is completed the part can still be used.

Dye penetrant inspection

Dye penetrant inspection (DP), also called liquid penetrate inspection (LPI) or penetrant testing (PT), is a widely applied and low-cost inspection method used to check surface-breaking defects in all non-porous materials (metals, plastics, or ceramics). The penetrant may be applied to all non-ferrous materials and ferrous materials, although for ferrous components magnetic-particle inspection is often used instead for its subsurface detection capability. LPI is used to detect casting, forging and welding surface defects such as hairline cracks, surface porosity, leaks in new products, and fatigue cracks on in-service components.

DPI is based upon capillary action, where low surface tension fluid penetrates into clean and dry surface-breaking discontinuities. Penetrant may be applied to the test component by dipping, spraying, or brushing. After adequate penetration time has been allowed, the excess penetrant is removed and a developer is applied. The developer helps to draw penetrant out of the flaw so that an invisible indication becomes visible to our inspectors. Inspection is performed under ultraviolet or white light, depending on the type of dye used - fluorescent or nonfluorescent (visible).

Ultrasonic inspection

Ultrasonic Testing (UT) uses high frequency sound energy to conduct examinations and make measurements. Ultrasonic inspection can be used for flaw detection/evaluation, dimensional measurements, material characterization, and more. To illustrate the general inspection principle, a typical pulse/echo inspection configuration as illustrated below will be used.

Ultrasonic Inspection is a very useful and versatile NDT method. Some of the advantages of ultrasonic inspection that are often cited include:

  • It is sensitive to both surface and subsurface discontinuities.
  • The depth of penetration for flaw detection or measurement is superior to other NDT methods.
  • Only single-sided access is needed when the pulse-echo technique is used.
  • It is highly accurate in determining reflector position and estimating size and shape.
  • Minimal part preparation is required.
  • Electronic equipment provides instantaneous results.
  • Detailed images can be produced with automated systems.
  • It has other uses, such as thickness measurement, in addition to flaw detection.

Positive Material Identification (PMI)

Positive Material Identification (PMI) is one of the more specialized nondestructive testing methods. With positive material identification the alloy composition of materials can be determined. If a material certificate is missing or it is not clear what the composition of a material is, then PMI offers the solution.

Because specifications for materials used in industry are increasingly more specific, the need for PMI

testing has been on an increase for the past several years. Periodic plant maintenance shutdowns are less frequent and consequently the materials used in the plant are in use longer. A wider variety of alloys that are indistinguishable to the eye are being used in process plants. When facility and inspection staff replace components, they must be able to guarantee that the new part matches required specifications.

Hardness Testing

Within the production and assembly lines, the hardness of materials or components is mainly tested for two reasons: firstly, to determine the characteristics of new materials, and secondly, for the purpose of quality assurance by meeting the required specifications.

 Mobile hardness testing is on the advance: in these times of cost pressure and higher quality requirements, it represents not only a quick but most of all an economical supplement to stationary hardness testing in the modern production process. The application possibilities are far ranging – this refers to both large and smaller components, especially at positions which are difficult to access.

ToFD (Time of Flight Diffraction)

ToFD is a sensitive, highly accurate and very fast NDT method for the inspection of buttwelds in carbon steel. The ToFD technique is fully code compliant (ISO and ASME) and can be used for welds starting thickness 6mm up to 300mm. This technique requires access from both sides of the weld (left and right) and can be used for vessels or piping.

With dedicated scanners and probes TÜV AUSTRIA Belgium offers rapid weld inspection that can replace radiography during day-time with only one operator. Flaws detected during scanning are immediately compared to ISO or ASME acceptance criteria and the report is generated the same day on site. Dangerous irradiation (RT) is not present. No need to develop films or travel to the dark room office.

Corrosion Mapping

Phased array testing helps make corrosion inspection fast and efficient. Our operators are trained and qualified to collect higher resolution data with fully encoded C-scan imaging. These images give a real top view color print of the internal surface.

With TRL Phased Array probes and a dedicated 2-axisscanner TÜV AUSTRIA Belgium offers efficient inspection options for detecting loss of wall thickness due to corrosion, abrasion, and erosion. This technique can also detect mid-wall damage, such as hydrogen-induced blistering or manufacturing-induced laminations, and easily differentiate these anomalies from loss of wall thickness.

Phased Array (UTPA)

Phased array ultrasonics (PA) is an advanced method of ultrasonic testing that has applications in medical imaging and industrial nondestructive testing. The Phased Array technique used for weld volume examination is fully code compliant (ISO and ASME) and can be used for welds starting thickness 6mm up to 125mm. This technique requires access from one side of the weld and can be used for vessels or piping (from 1”) in carbon or stainless steel.

With dedicated scanners and probes TÜV AUSTRIA Belgium offers rapid weld inspection that can replace radiography during day-time with only one operator. Our trained and highly experienced operators will compare the dimensions of detected flaws to ISO or ASME acceptance criteria and the report is generated the same day on site. Dangerous irradiation (RT) is not present. No need to develop films or travel to the dark room office.

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