A vision inspection/analysis procedure for card clothing has been created by researchers from the Faserinstitut Bremen Research Institute (Bremen, Germany) and Chemnitz University of Technology (Chemnitz, Germany).
Card clothing is made of durable material and typically has a rubber or leather fillet with wire teeth embedded in it. A carding machine’s rollers or cylinders are covered with card clothing. The material that needs to be “carded” is moved between cylinders that move differentially and are covered in card clothing. To create a continuous web fit for further processing, fibres must be disentangled, cleaned, and mixed during the carding process.
However, the wire teeth wear down and become damaged as a result of this constant contact to rough raw fibres, which lowers the wire’s quality. Fischer notes that card clothing experiences a far higher degree of wear than other types of fibres when high-performance fibres, such as carbon, glass, or aramid, are processed in the nonwovens industry. Presently, regardless of wear level, all card clothing on all card machines on non-woven production lines needs to be changed on a regular basis in accordance with recommended maintenance schedules. This is done in order to minimise unplanned delays or interruptions to production. However, this is also a costly procedure in terms of labour, idle time during manufacturing, and lost raw materials.
Using a camera and lens fixed on an aluminium rack above a production line, Fischer and his team created their inspection system. Following that, team members might manually move the camera into the proper orientation for scanning card cylinders.
Fischer and his team utilised software to move the camera along the track automatically so that it could take pictures of each carding cylinder during the inspection procedure, which was carried out during scheduled maintenance intervals for the manufacturing lines while the maintenance doors on the machines are open. Fischer’s team’s AI software was used to transmit, store, and analyse the picture data on the laptop.
The camera system can easily detect the card clothing teeth from back, front, and working angles, as well as detect damaged edges and tips, and the images data does enable a reproducible analysis.
As of now, the system needs more development in order to be used in an industrial way, but the research team has looked at this promising technology which will be useful in the future.