The engineering principles behind effective web cleaning
Weducon’s HE and HEM series are designed for non-contact removal of dust, fibres, and other loose contaminants from moving webs and sheets under stable process conditions. Our systems are engineered to deliver consistent cleaning performance across a wide range of production environments and substrates.
Reliable results depend on an understanding of how air and contaminants behave around a moving substrate, how static charge affects particle adhesion, and how airflow can be controlled without disrupting web stability. This is where engineering and continuous development make the difference.
Experience and development: essential for effective web cleaning
Weducon’s web cleaning technology is built on decades of experience, continuous development, and close analysis of changing production processes.
Production environments are not uniform or static. They evolve, and so do the demands placed on cleaning technology. Requirements related to energy use, noise exposure, clean production, waste prevention, and system integration are more demanding than they were years ago.
Weducon continues to develop its technology in response to these changing requirements, with a focus on effective cleaning, process stability, efficient system design and practical integration into the production line.
How the Weducon cleaning process removes contamination
An effective web cleaning process starts with the airflow generated by the moving substrate. As a web moves through a production line, it entrains surrounding air and creates a near-surface airflow commonly described as a boundary layer.* The air directly adjacent to the moving surface is carried along with the web, while its velocity decreases with increasing distance from the surface.
Loose dust, fibres and other particles carried along with the moving web are transported within this near-surface airflow. Other particles remain on the substrate and may be held there by electrostatic or other adhesion forces.** A boundary layer should therefore not be regarded as a physical membrane holding contamination against the web: near-surface airflow and particle adhesion are related aspects of the cleaning problem, but they are not the same phenomenon.
The way this airflow enters the cleaner is important. An abrupt obstruction would disturb and redirect the web-generated airflow before it reaches the cleaning zone. The angled inlet of the Weducon cleaner is therefore designed to guide the incoming near-surface airflow gradually into the cleaner.
This allows the web-generated boundary-layer airflow and the loose contamination carried with it to enter the controlled cleaning zone before that airflow is deliberately disturbed. Weducon refers to this controlled capture of the web-generated near-surface airflow as boundary-layer absorption.
Particle adhesion → detachment → transport → capture
Once inside the cleaner, the original web-induced airflow is deliberately disrupted and replaced by a controlled cleaning airflow close to the substrate.
The restricted cleaning passages and fan-generated clean airflow create high local air velocity along the surface. The resulting aerodynamic forces mobilise loose and surface-held contamination so that it can be transported directly towards the extraction chambers.***
At the same time, active ionisation inside the cleaner neutralises static charge and reduces the electrostatic component of particle adhesion. This makes electrostatically affected contamination easier to mobilise by the cleaning airflow and limits immediate re-attraction after cleaning.
The Weducon cleaning process therefore combines controlled entry of the web-generated airflow, aerodynamic particle mobilisation, electrostatic neutralisation, immediate extraction and containment.
Red lines:
The moving web entrains a near-surface airflow that carries loose dust, fibers and particles towards the cleaner. The angled cleaner inlet guides this web-generated airflow into the cleaner before it is deliberately disturbed inside the controlled cleaning zone.
Active ionisation:
24 V DC ionizers neutralize static charge inside the controlled cleaning zone. Reducing electrostatic particle adhesion helps the cleaning airflow mobilize affected particles and limits immediate re-attraction after cleaning.
Blue lines:
Filtered air from the filter/fan unit is returned to the cleaner and directed close to the substrate. This airflow transports the generated ions, supports web stability and creates the local air velocity required for non-contact cleaning.
Purple lines:
This is air drawn in from the areas behind the cleaner, where the original incoming boundary-layer flow has already been disrupted. The inward airflow helps contain contamination within the cleaner and prevents its dispersion into the surrounding area.
Controlled airflow instead of compressed air
Non-contact web cleaning depends on precisely controlled airflow close to the substrate. Weducon does not use compressed air for the cleaning process.
Instead, the matching filter/fan unit generates and recirculates the airflow required for cleaning and extraction. Extracted contaminated air passes through the filtration system, after which the cleaned air is accelerated by the fan and returned to the cleaner.
The cleaner geometry directs this fan-generated airflow through restricted passages close to the substrate. The resulting local air velocity provides the aerodynamic cleaning action while also helping to stabilize the moving web.
At the same time, the extraction side removes the incoming web-generated airflow together with mobilized contamination.
The extraction airflow exceeds the amount of clean air supplied inside the cleaner. As a result, additional surrounding air is drawn into the cleaner rather than contaminated air being blown outwards. This airflow balance supports immediate particle capture and containment.***
Why ionization matters in Weducon non-contact cleaning
Static charge reduces cleaning effectiveness by increasing particle adhesion to the substrate or by attracting contamination again immediately after cleaning.**
For the Weducon cleaning principle, active ionization is an integral part of the controlled cleaning process. It works together with the cleaning airflow rather than acting as a separate particle-removal mechanism.
The ion generators are positioned inside the central cleaning zone. This position is deliberate: static charge is neutralized where the controlled cleaning airflow can immediately mobilize and capture affected contamination.
The positive and negative ionization elements are positioned longitudinally offset rather than directly opposite each other. This prevents the opposing ionization zones from directly counteracting each other and allows the generated ions to be transported effectively towards the substrate by the cleaning airflow.
These ionizers, with protection class IP66, have integrated high-voltage power supplies and provide real-time feedback on performance and technical failures.
Energy-efficient airflow, low noise and self-cleaning filtration
Effective web cleaning should not come at the cost of excessive energy use, noise exposure or frequent filter maintenance. Weducon therefore designs the cleaner head, airflow control and filter/fan unit as one integrated system.
Frequency-controlled fans adjust the airflow to the cleaning requirement without the heat, resistance and energy losses associated with valve-based mechanical regulation. Depending on the configuration and the system being replaced, energy use can be reduced by 20–30%.
The aerodynamic design of the clean-air supply and extraction chambers helps prevent particle build-up, improves airflow efficiency and can reduce operating noise by up to 10 dB compared with earlier or conventional designs.
Matching self-cleaning filter/fan units separate extracted contamination from the airflow and return purified air to the cleaner. This supports stable performance with limited maintenance and consumable use.
Control and integration options
Effective web cleaning also depends on how well the system can adapt to changing production conditions. Festo® multi-step cylinders allow step-by-step adjustment of the distance between the two sides of the cleaner, helping maintain the appropriate cleaner opening for different substrate thicknesses.
The cylinders are controlled via a standard interface containing the required electrical and pneumatic components. This interface connects the cleaner, the filter/fan unit and the machine or production line into which the system is integrated.
Control options include:
- manual operation
- machine- or line-generated impulses
- standalone operation supported by the optional Automatic Impulse Generator (AIG)
The AIG supports efficient system use by controlling functions such as:
- substrate thickness measurement
- response to order changes
- opening and closing of the cleaning device
- starting and stopping the filter/fan unit
Cleaning technology – FAQ’s
2. Weducon cleaning technology
No. A boundary layer is a near-surface airflow created as a moving web entrains surrounding air. It is not a physical barrier that prevents non-contact cleaning. It does, however, mean that airflow close to the web must be deliberately controlled.
In a Weducon cleaner, the incoming web-generated airflow is guided into the cleaning zone before it is deliberately disrupted and replaced by controlled cleaning airflow. Aerodynamic forces can then mobilize contamination close to the surface, while extraction immediately captures the released particles.
Learn more about how Weducon’s web cleaning technology works.
Production processes, materials, and requirements continue to change. Higher recycled content can change contamination loads, while lean production increases the focus on stable output with less waste, energy use, maintenance, and unnecessary production stops. Noise exposure, dust containment, and efficient system integration are also increasingly important.
Weducon therefore continues to develop airflow efficiency, filtration, controls, noise reduction, and system integration in response to these production requirements.
Developments such as the EU Packaging and Packaging Waste Regulation (PPWR) and the broader move towards circular production further increase the importance of material efficiency and preventing avoidable production loss.
Read more about PPWR, production loss, and saleable output and reducing production waste in packaging and printing.
Simple vacuum extraction primarily relies on air being drawn towards an extraction opening. Active non-contact cleaning also creates controlled airflow close to the substrate to mobilize contamination before it is extracted.
In a Weducon system, fan-generated cleaning airflow, ionization, and extraction work together within the cleaner. The extraction airflow exceeds the supplied clean airflow, helping to capture released contamination and contain it within the system.
Suction capacity alone therefore does not determine how effectively particles are removed from the substrate.
3. System selection, integration and operation
A suitable web cleaning method should achieve the required cleaning result under actual production conditions and maintain that result at an acceptable total operating cost.
This means looking beyond purchase price. Relevant factors include the substrate and contamination, production speed, installation position, energy use, consumables, maintenance, operator intervention, and production downtime.
Contact cleaning can be the right choice where contamination adheres strongly to a suitable substrate. Contact and non-contact methods can also complement each other. For example, non-contact pre-cleaning can reduce the contamination load reaching a contact cleaner, reducing consumable use and maintenance requirements.
The most useful comparison is therefore the cleaning result achieved under actual production conditions and the total cost and effort required to maintain that result over time.
See our label and narrow-web contamination control page for an example of this application-based approach.
Cleaning technology for various production environments
Weducon offers non-contact cleaning solutions based on the same underlying engineering principles, ranging from compact systems for 450 mm label and narrow-web applications to engineered solutions for paper and board production lines with substrate widths of up to 14,000 mm. Each configuration is adapted to the substrate, process conditions and production environment.
Weducon applies these engineering principles across its HE and HEM series, with configurations developed for different production environments, including Corrucleaner® systems and dedicated designs for tissue and nonwoven substrates.
Looking at a specific substrate, contamination issue or machine layout? Get in touch with Weducon for application-specific advice on system configuration, control options and integration.
Scientific references
* Moving-web airflow and boundary-layer behaviour
Arzate, A. & Tanguy, P.A. (2004). Air entrainment on a moving continuous web. Chemical Engineering Science, 59(17), 3527–3536.
View scientific publication
** Particle adhesion and electrostatic forces
Feng, J.Q. & Hays, D.A. (2003). Relative importance of electrostatic forces on powder particles. Powder Technology, 135–136, 65–75.
View scientific publication
*** Aerodynamic particle mobilisation, extraction and containment
*** Henry, C. & Minier, J.-P. (2014). Progress in particle resuspension from rough surfaces by turbulent flows. Progress in Energy and Combustion Science, 45, 1–53.
View scientific review
*** Grinshpun, S.A., Yermakov, M. & Niu, X. (2022). Novel techniques for cleaning surfaces contaminated with solid particles. Aerosol Science and Technology, 56(7), 665–672.
View scientific publication
The Grinshpun study uses compressed-air jets combined with immediate vacuum extraction. Weducon does not use compressed air; its relevance here is the independent demonstration that aerodynamic particle mobilisation can be combined with immediate extraction and containment.
