TPT November 2018

I NSPE C T I ON , T E S T I NG & QUA L I T Y CONT R OL

Characterisation of surface defects in tubes THE management of surface defects in tubes and pipes is one of the main areas of interest in the production process. A surface crack or a hole can be the origin of a crack or a corrosion process when the element is in service.

Non-destructive testing is the best method for both detecting and charac- terising defects. Once the defect and its typology are known, the challenge is to characterise them and establish the rela- tion to the cause that produces them, so that corrective actions can be implement- ed in the process to avoid future occur- rences. In addition, the characterisation of defects is one of the most interesting research subjects, and its combination with artificial intelligence tools and algo- rithms will result in a deep and evolution- ary knowledge orientated to the continu- ous improvement of surface quality. Currently, themost widely usedmethod is based on the eddy current or Foucault phenomenon. A conductive coil will generate an alternate electric current that will produce a magnetic field. When this field is in the presence of a conductive material (the material to be tested), an induced current (and a magnetic field) as reactive will be produced. Once both the injection field and the induced field are known, whenever a discontinuity occurs in the inspected material it will respond with a different signal than expected, which results in a change in impedance. It is represented in a diagram, as a curve that is usually called ‘bow’. The study of these curves, their amplitudes and their phases, and

Characterisation of surface defects through eddy current equipment

nificant training and clean environment conditions that are not always possible in manufacturing lines. The key is not the recognition of the defects, but their real-time characterisation. To do this, a com- bination of efforts is required: the accuracy of the eddy current system, the easy interpretation of the images and the intervention of operators and analysts to close the cycle. ISEND has developed a new non- destructive testing system called EDDYeyes for the inspection of surface quality that combines eddy current equipment with direct vision cameras. Using algorithms for the treatment of the data, high productivity is achieved even for the most adverse conditions such as the production of hot wire rod of 4.5mm diameter at more than 120m/s.

services, ensuring professionals can make faster decisions within their daily workflow, whether creating floor plans and estimating building installations or documenting construction progress and creating as-built facility documentation. “The BLK3D is the latest addition to our award-winning BLK series,” said Ola Rollén, Hexagon president and CEO. “The ability to capture, visualise and index precise 3D measurement information directly from a 2D image raises the bar, setting new expectations for professionals looking for faster, more accurate ways to get the measurements they need. the comparison with the real material is a way to characterise the defects. To be effective, the quality-control staff must create alarms or thresholds to differentiate what is a defect and what is not. However, this is not always easy or even possible, because locating real defects and comparing them with the signal produced can require measurement of parameters that are not simple, such as instant speed. A new and sophisticated way to approach this task is the use of vision in combination with the eddy current. The principle is that whenever a defect occurs and is detected by the eddy current, a set of cameras take an image in real time and associate and store it with the signal for further analysis. This could seem easy, but some parameters have to be very well controlled, such as speed, real position or depth of the defect. There has been notable progress in the recognition of defect patterns only with images. However, this requires sig-

ISEND, SA – Spain Email: contact@isend.es Website: www.isend.es

Compact 3D handheld imager HEXAGON AB, a digital solutions specialist, has introduced a new addition to its BLK line. The Leica BLK3D compact 3D handheld imager improves productivity by enabling immediate and precise 3D measurements from any image it captures.

“Not only that, it’s so easy to operate, virtually anyone can use it.” With the expanded functionality of the desktop software, users can create new projects and CAD-ready 3D models from measurable images. BLK3D connects to a laptop or desktop computer via Wi- Fi or USB cable. Data is automatically synced, and measurable images can be accessed, processed and organised from the convenience of the desktop application.

By combining measurement sensors, software and on-device edge data processing capabilities, the BLK3D enables in-picture measurements with professional-grade accuracy. Every image captured by the BLK3D is a complete and precise 3D record. Its edge capabilities eliminate the need for network connections and/or cloud

Hexagon AB – Sweden Fax: +46 8 601 2621 Website: www.hexagon.com

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NOVEMBER 2018