By: Jeffrey Noruk
This is what Industry 4.0 visual weld inspection looks like
Visual inspection is the first line of defense against allowing a defective welded product to reach the customer. While visual inspection is relatively easy and inexpensive to do, it suffers from the inherent weakness that a human is involved in interpreting the results. It has been proven that:
- After one hour of weld inspection the inspector is typically only 70% effective.
- Subjectivity leads to changing acceptance criteria between inspectors.
- Hand, eye and brain coordination limits how fast inspection and documentation can be done.
A portable laser scanner (Figure 1) can provide a completely consistent inspection result at a pace 5X faster than a person with traditional gauges.
Figure 1. WiKi-SCAN handheld welding quality management system
In addition, full results are automatically saved including dimensions, pictures and comments which are date and time stamped. These results can be quickly downloaded to a PC and shared with others via the Cloud. The WiKi-SCAN is IoT ready and can integrate easily into one’s Quality Plan for useful data analytics (Figure 2).
Figure 2. IoT Actionable Data
The WiKi-SCAN can be used in any industry for all types of welds on any material. A few of the typical applications where customers have seen dramatic improvements in weld quality and productivity include the following.
Critical Weldments – Wind Towers, Pressure Vessels, Bridges
Critical features needed to be measured on every weld made to join the multiple sections of a wind tower. Inspectors with manual gauges were doing this but results were not consistent, fast enough or documented as well as their OEM customer required.
The WiKi-SCAN can measure all five weld features (undercut, toe angle, height, width and mismatch) critical in insuring fatigue life is acceptable. This can be done with one quick laser scan whereas prior to this it took four different special gauges and several minutes to complete (Figure 3).
Figure 3. Weld Measurements
Weld inspection is now much more consistent providing for a quicker signoff from the OEM on the inspection report. Rework is reduced, inspection is faster and the ability to do more fit-up checks during tacking of the tower sections has improved overall tower weld quality.
Industrial Products – Process Improvement
As the saying goes, “What gets measured gets improved”. One needs to have quantifiable data rather than just a Go/No-Go results, to make improvements. Without actual weld measurements one cannot use standard SPC tools to focus on where the problems actually are.
The WiKi-SCAN provides complete dimensional data for every weld and joint inspected with a date & time stamp as well as the weld identification number. From this information, statistical control and process capabilities can be determined. One can then focus on where improvement is needed and how to achieve it. In conjunction with this, welds and welders can be given a score to provide a way to measure improvement (Figure 4).
Figure 4. Weld Process Capability
Utilizing statistical analysis has resulted in improved weld quality, reduced repair and less over welding. In addition, new robot welding system runoffs include having welds measured by the WiKi-SCAN to support initial acceptance and to provide a baseline for future improvement.
Most manufacturers do not weld all the parts that go into their product but instead rely on suppliers to supplement their own capabilities. The difficulty with this is how to insure all welds meet the minimum quality standard and second how to determine which suppliers are doing the best job.
The WiKi-SCAN can be used as the “referee” to set up a consistent method for the customer and supplier to agree on what is considered an acceptable weld. The supplier no longer has to guess whether the parts sent to the customer will be acceptable, because both parties are measuring the welds with the same objective system. To expedite auditing, the supplier’s results can even be sent via email or saved to the “cloud” so the customer can review the results before the parts are shipped.
Customers and suppliers are better aligned in their quality expectations thus reducing disagreements and fostering continuous weld improvement. This has reduced unnecessary repair, over welding and delays in deliveries.
Interested in learning more about Servo Robot’s WiKi-SCAN weld inspection system? Check us out at https://servo-robot.com/wiki-scan-brochure/ to see a video showing the WiKi-SCAN in action.