Here you can find frequently asked questions and answers about web cleaning, sheet cleaning, and removal of contamination in manufacturing processes.
Furthermore, you’ll find answers about the effects of dust elimination on production, quality, working conditions, and energy use.
Web cleaning strips moving webs and sheets of harmful contamination: dust, fibres and particles.
Contamination can be caused by:
- the substrate or product (paper, board, tissue, nonwoven, etc.)
- the production process (slitting, scoring, cutting, trimming, die cutting, etc.)
- dust and particles in the production area that are attracted by the static charge of the moving web
Web cleaning prevents these types of contamination that end up on final products. It prevents waste, poor printing quality and health risks for both workers and end-users.
There are several web cleaning methods:
- Non-contact web cleaning: web cleaning via strong airflows or corona.
- Contact cleaning: web cleaning via mechanical forces. For instance, sticky polymer rollers, rotating or stationary brushes, moisture and even fire.
Product and process parameters determine which web cleaning method is right for you.
Web cleaning is necessary when dust and particles cause problems during processing or jeopardize quality or health.
Think, for instance, about contamination during medicine or food packaging, or loss of quality during printing, laminating or coating. There is also the possibility of processes, such as digital printing, being disrupted because of contamination.
The benefits of web cleaning depend on your production process, product and converting.
The right web cleaning method for your production process depends on a variety of factors, including:
- sensitivity of the surfaces to be cleaned.
- level and type of contamination.
- web speed.
- web tension.
Every kind of moving surface has its specific properties.
Fibrous webs such as tissue or non-woven, for instance, can’t be cleaned via contact cleaning. The mechanical forces of the cleaning not only gets rid of the contamination from the web, but also damages the structure and surface of the web.
Film and foil can be cleaned perfectly by means of sticky polymer rollers. This is because the surface of the web has a good mechanical resistance against the cleaning power and the level of contamination is usually moderate.
Textiles need a non-contact method, because increasing web tension leads to a variation in web width. These are just a few examples of the aspects that are involved when choosing the right web cleaning method.
The advantages of web cleaning are numerous. Depending on your process, the advantages include:
- prevention of printing problems
- lengthening of wash up distances
- avoiding inclusions
Quality issues such as hickeys or bulls eyes are typical printing problems caused by debris on the print surface, such as chop or slit edge debris or chives. With the right web cleaning solution, the wash-up distance can easily be doubled or tripled.
Another reason to use web cleaners is to avoid inclusions when laminating, so that you will not laminate contaminants onto the surface of packaging products.
These are just a few examples of the benefits of well-performing web and sheet cleaners.
The best position to install a web cleaner depends on your process.
For example, normative is a position that is as close as possible to the source of the debris.
Some factors to consider are: what is the objective? If the goal is lowering emissions in the production area, a position early in the process might be ideal.
If the main goal is to increase the quality of printing, a position close to the first printing unit should be chosen.
Other objectives could be the elimination of debris between layers in a ‘reel-to-reel’ process, where a web cleaner is positioned as close to the rewinder as possible. In this case, our many years of experience and quality work would be a great advantage.
Yes, you can use a web cleaner in more than one position. Depending on your production, this can be necessary for optimal cleaning results.
In a corrugator, for instance, web and sheet cleaners are used in the dry-end. In high-end production, a web cleaner is positioned directly behind the slitter/scorer before the pull-roll section. More units are used after several levels of cut-off as sheet cleaners.
Weducon® can integrate all these different cleaners into one system. For more information on this specific application, visit corrucleaner.com
This depends on the type of web cleaner you need for your production process.
Weducon® carries two different types of non-contact web cleaning devices in the HE-web cleaner series. Taking your circumstances and needs into consideration, a choice can be made.
The cleaner itself requires either 225 or 340 mm of free web path, depending on the type.
The rest of the components, such as the required filter/fan unit, can be placed outside the direct production environment if sufficient space is available.
By using laser-welded smooth ducting, both the pressure drop and resistance is limited, meaning the distance is not too critical.
Because Weducon® supplies made to measure web cleaning systems, we are able to compose a configuration that fits your process, production circumstances and space limits.
Weducon’s non-contact web cleaner doesn’t disturb your production process.
The applied active ionisers (24V DC) do not charge the substrate.
The use of high-quality filtration prevents the blow-back of particles into the production surroundings.
Due to the non-contact principle of the cleaning activity, there is no risk of damaging sensitive coating layers or leaving marks or traces on the substrate.
The non contact cleaning performance functions via a strong airflow, high volumes and airspeeds. Therefore, the installation produces a certain level of noise.
Our filter/fan unit does not exceed 80 dB, and the cleaning device never exceeds 85 dB.
Operation of a web cleaner is rather simple.
Weducon® has trained installation- and instruction specialists.
After installation, the daily users get a training to operate the web cleaner in the most efficient way.
It is important to learn how to use and to benefit from these systems.
Besides the knowledge gathered during these instructions, no further specialised skills are needed.
Maintenance costs of our web cleaners are low.
Weducon® web cleaners do not solve your dust problem with heavy maintenance or endless amounts of consumables.
The design of our web cleaner reduces energy consumption by 25%. And because the system is electronically controlled, no energy is wasted by adjusting the flow through a barrier valve.
Besides annual maintenance, the only regular task is to empty the dust container. The number of times you must do this depends on the amount of debris caught by the web cleaner.
The performance of a web cleaner can certainly be measured.
When used in printing processes, the improvement of print quality and the lengthening of wash-up distances indicate how well the system works.
Furthermore, the use of particle counters, or the comparison of dust samples, is a reliable indicator.
Finally, the amount of dust collected in the dustbin is another way to check and compare performance.
Read the report about the web cleaning results at Mayr-Melnhof paper and board. In this case, the amount of dust removed by our HE 90 web cleaner exceeds the customers’expectations.
Weducon® supplies the HE series web cleaners in the majority of Europe, directly to end-users as well as O.E.M.’s.
Do you have more questions about web cleaning?
Please use the form if you have another question about production improvement and web cleaning in your particular production process.
Or get in touch with us: we’ll gladly help you find out if your situation could benefit from web cleaning.