09 | 05 | 2021
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Welding Head Movement and Welding Seam Inspection
with MEL Laser Scanner

With the M2-iLan Laser scanners series of scanners are available combining with up-to-date know how from optoelectronics, digital image processing and decades of experience in the measurement technology implemented.

  • Automatic control of the intensity of the laser-beam 
  • Clever, smart image-processing 
  • Future-proof due to firmware-updates 
  • Switchable between Ethernet TCP / UDP 
  • IP address can be generated by the browser 
  • Robust construction 
  • W-version up to 500°C during continuos operation by water-cooling  
  • i-LAN scanner with integrated electronics

Welding Head Movement

The automated welding head movement with a Laser scanner ensures that the welding head is always in the best possible welding position relative to the welding groove. The laser scanner generates a scan line diagonally to the welding direction. Thereby it is possible to determine exactly the contourline of the surface. With the software MEL SeamTrax the welding seam is detected automatically. Using the customer-specific guidelines for the best possible position for the welding head the drive is controlled well-directed enabling the welding process done from the best possible position.

The opportunities by the use of the laser scanners for the tracing of the welding head or of control systems exceeds the simple use for automatised welding of lengths. Also weldings for „interlaced“ workpieces can be precisely recorded with the support of scanners.

Don't hesitate to contact us with your intended use.
  M2D-W und M2W-iLAN Scanner

The W-Series: Water-cooled laser scanner for the use at temperatures up to 500 °C .

MELTrax Software for Welding Head Movement

With its tools and filters, MELTrax comes up with wide spectrum of functionallity.
Below you'll find selection with functions especially for welding applications:

  • Profile Detection
  • Seam Tracking
  • Welding Head Movement
  • Groove Tracking
  • Gap Detection
  • Welding Head Movement
  • Groove Tracking
  • Gap Detection
  • Welding Head Movement
  • Groove Tracking
  • Welding Head Movement
  • Groove Tracking
  • Angle Measurement
  •  Angle of Objects
and further functions.

The modulary architecture of MELTrax supports client specific application solutions.

Don't hesitate to contact us with your application requests.


The filters help with difficult surface – rough, shiny, mirroring. Scintillating reflections create unwanted optical effects (speckles). Therefore, MELTrax is equipped with the most different filters for the optimization of the laser intensity or videostrengthening.

Vektor Toolbox

The vector tools are very useful to optimize the evaluation of the camera picture. The result is a vector based profile detection.



Welding Seam Inspection with Laser Scanners

Welding is a process which is influenced by many factors. The type of the material, the complexity of the applied welding technology as well as the operating conditions [e. g. temperature, air humidity] are decisive for a good welding result. Therefore it is important to check the welded connections. The two most commonly used inspection methods are the optical check (visual check) and the inspection using ultra sonic sensors. For both inspection methods the use of a laser scanner delivers significant advantages if the target is to reduce the time needed for the inspection of the welding seams without worsening the quality of the inspection.

Optical welding seam inspection with laser scanners

The laser scabber is moved along the welding seam for the optical inspection of this seam. Thereby the scanner is positioned so that the generated scan line is diagonally to the welding seam. So a 3D image of the surface of the welding seam is generated which is analysed by the MEL Software (product name) regarding irregularities. If the structure deviates more than the adjusted tolerance a corresponding signal is put out via a profi bus or the Ethernet.

By using the MEL system solution for the inspection of welding seams irregularities are detected in a reliable way:
  • Welding seam is partly or completely missing
  • Double welding
  • Splashes / slag
  • Pores
  • Seam too thin or too thick
  • Position of the welding seam
  • Waviness

3D-images of the Welding Seam

The "false colour representation“ of the 3 D image which is generated by the software shows clearly irregularities of the welding seam.
3D Abbildung einer guten Schweißnaht 3D Abbildung einer fehlerhaften Schweißnaht
3D image of a good welding seam 3D image of a defective welding seam

Inspection of the welding seam with ultra sonic sensors
The laser scanner is used for the constant movement of the ultra sonic sensors in the perfect position for the measurement during the ultra sonic inspection. Thus curves in the welding length are no problem at all and the correct inspection of the welding seam is ensured. 

Welding Technologies

We have a vast array of experience with the use of laser scanners for the inspection of welding seams with a large variety of welding technologies. In principle the use of the laser scanners is possible for the inspection of welded connections of all commonly used welding technologies:
  • Submerged welding
  • Electrode welding
  • Gas-shielded welding
  • Laser welding
  • Ultra sonic welding
  • Tungsten-inert gas welding – metal active gas welding
Don't hesitate to ask us about your intended use.

Detection of Irregularities

like e.g.:
  • Welding seam is completely or partly missing
  • Double welding
  • Splashes / slag
  • Pores
  • Seam too thin or too thick
  • Position of the welding seam
  • Waviness
are detected reliably by the software and put out using the designated interface.

Here, you'll find an overview of our 2D/3D Profile Sensors weCat3D.



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