Summary
Nonwovens can be found everywhere. They’re in-dispensable in consumer products, in patient care and for industry – and yet not usually visible but still required to be defect free. 100 % product quality – which can only be ensured with an in-line inspection system – is an important precondition for establishing yourself as a high-end supplier and to provide solutions for customers’ future needs.
Challenges
TWE Diersdorf is a manufacturer and supplier of high-quality nonwovens in sensitive hygienically area. TWE is the premium supplier in this segment, and produces for well-known, globally-positioned customers. Surface inspection requirements for TWE go beyond mere fault-finding and quality assurance; they also include sustainable process control and optimization. The goods are produced and inspected and then immediately shipped. Therefore a 100 % reliable and completely automated process is required in order to avoid interim storage. Realizing this, TWE chose ISRA VISION as its partner in the deployment of several such solutions in order to systematically and continuously improve its production.
Solution
The web inspection systems detect defects such as dirt, thick areas, thin spots and holes. A total of six lines have SMASH inspection systems installed, including four already in 2008. The line widths are between 2,200 mm and 3,600 mm and the maximum speeds are between 20 m/min and 120 m/min. The inspection systems allow to assess the quality immediately. The production release is therefore instantaneous. In upstream processes, higher production reliability has been achieved, as defects can be detected earlier and corrected.
Two of the lines already have the optional Data Mining module that provides additional potential for productivity gains by efficiently bringing together the output and error data, and providing analysis by date or time, batch, defect class, product type or work shift. Intelligent linking uncovers relationships and the potential for optimization of even automated processes at different process stages. In addition, the Enterprise Data Mining Tool brings together information from several lines at different production sites.
In order to continue to improve synchronized production steps, TWE Dierdorf decided to use ISRA’s Rewind Manager on a new production line. By doing so, the nonwoven manufacturing and post-processing are integrated in-line. The Rewind Manager at the rewinder receives the inspection data from production. Synchronization of the data ensures that the line stops at the position of a defect. This allows for fast repairs.
Results
With the lines’ inspection systems, quality is systematically monitored and assessed. This has improved the quality of TWE’s produced goods. In addition, the material quantity produced is used more efficiently. The measurable production benefits were achieved just four months after the introduction of the inspection systems. TWE can now assure customers a 100 % high-quality product and plans to network several production lines.
“Especially in the demanding hygiene sector, ISRA has a good reputation. ISRA systems allow for better process control and customer claims have decreased. The inspection systems allow us to assess the quality immediately. At ISRA, service takes highest priority. Technicians are sent onsite as needed. They are technically very com-petent, very helpful and friendly and keep the communication lines open.”
Stefan Hoben
Technical Services Manager
TWE
Key figures
Weight range
from 80 g/m2 - 250 g/m2
Material thickness
0.8 mm to 3.0 mm
Line widths
up to 3,600 mm
- Online slitting in narrower widths possible
- SMASH inspection systems for six lines
- Different cameras based on tasks
- Frames provide optimum protection for components and electronics
- Lighting based on task: fluorescent or LED