Welding Test Unit


The welding wire test unit allows the objective assessment of welding wire properties by operator-independent experimental welds under controlled and repeatable conditions. That provides information on systematic further development and quality assurance. During welding measurements like feedability and electronic voltage loss in the contact tip are recorded. The rotating work piece allows long-time tests, so that variations in wire surface quality regarding particles, roughness and consistency as well as performance in the contact tip and contact tip wear can be detected.

The following measurements are recorded by the computer of the welding test unit and displayed as a chart on the screen:

  • feeding force (F)
  • welding current (I)
  • welding voltage (U)
  • electronic voltage loss in the contact tip (dU)
  • noise level during welding
  • temperature curve of the contact tip (T)
  • wire speed after wire feed (VD1)
  • wire speed before contact tip (VD2)
  • smoke density

The chart (Picture 2) shows measurement curves of a customary stainless steel welding wire in need of improvement. The simultaneous fluctuations of the feeding force and the welding current curve show micro arcs and welds in the contact tip. They finally lead to complete fusing of the wire with the contact tip and interruption of the measurement. The high and very irregular voltage loss probably is caused by contamination of the wire surface.

The voltage loss of a good copper-plated wire is less than 25 mV, that of a good blank normal steel wire less than 100 mV.

Testing Curves (flux-cored stainless steel welding wire with a diameter of 1.2 mm)

Commercially available product The same wire after welding wire finishing with HELICORD®

Further properties:

  • The welding current can be set up to 500 A during permanent operation.
  • Measuring data are recorded at 5 kS/s and an analog digital converter resolution of 16 bit.
  • The welding speed can be set up to 3,000 mm/min.
  • The operator is guided through the measurement by touch screen.
  • The measurement report can be printed by the colour laser printer included in the delivery.
  • Temperature curve of the contact tip.