Powder Coating I Fully automated coating center

Integrated approach
reduces production costs
A new coating center combines powder preparation, feeding, dosing and color change in a closed,fully automated system. This integrated approach leads to increased productivity with consistently
high quality and, for the first time, enables the configuration of a fully automated powder coatingsystem.

Michael ToppWagner‘s new IPS coating center represents an innovative solution for thesediverse challenges. It is a fully automated system that enables decisive improvements in the powder coating process.
The abbreviation IPS stands for „Integrated Powder System“ and reflects the basic
concept of the new coating center.
The integrated approach allows to achieve increased productivity while maintaining high quality and ease of operation.

© J. Wagner

Globalization and digitalization increase the competitive pressure in the industry – also in the field of powder coating.
Plant availability and productivity must
therefore continue to rise. At the sametime, end customers are demanding evermore individual products, leading to smaller batches and more frequent color changes. Added to this is the shortage of skilledworkers, which is already affecting performance and quality in some countries.

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In combination with an automatic powder booth, a powder recovery system andguns, a fully automated powder coatingsystem can be configured for the firsttime.

Constant results thanks toa high degree of automation
At the heart of the coating center, the IPS
Master, powder preparation, feeding anddosing are integrated, including an ultrasonic sieve as an important component forgood coating quality. The high degree ofautomation ensures constant process sequences; there are usually no personnelrelated fluctuations. While, for example,
conventional powder centers have to becleaned manually by the operator, which
exposes him to powder dust and pollutes
the surrounding area, the IPS cleaning
process runs completely automatically ina closed system.
The cleaning intensity can be adjusted
according to the color change. This has
a significant effect on the average color
change time and allows an easily com-Powder preparation, feeding and dosing areintegrated in the new coating center. The possibilityof working with two boxes considerably increases
the available time interval for the box change. Thecoating time gained adds up to a significant
productivity increase.

prehensible reduction of several minutes.
The automated color change and easy
operation via a flexibly positioned touchscreen also reduce the risk of operating
errors, which can quickly lead to rejects
and renewed cleaning.
Many plant operators are confronted witha shortage of skilled workers. They face
the question of how they can achieve consistently high coating quality without experienced specialists or frequent personnel changes. With IPS, manual activities
are replaced by automated processes. This
produces constant results and makes production planning much easier.

The powder removal takes
place at the bottom of thecontainer and is controlled
by a dosing valve (top). At
the outlet of the dosing
valve, the powder isaccelerated and brought to
the guns by air conveyance.
By decoupling powder
supply and furthertransport, up to 400 gramsof powder per minute canbe conveyed at 30 meters(bottom).

In the case of an injector, it is often criticised that the conveying capacity is reduced by wear over several weeks. Pump
solutions on the market offer better longterm constancy with a rather complex system. However, the simple design of the injector allows easy maintenance, which,when carried out regularly, also ensures
good and constant coating results.
The Integrated Powder System is neither apump nor an injector. The term Smart Feeding Technology (SFT) comprises several
functional units which are responsible as
an integrated system for optimum powder preparation and feeding. Fresh powder
and recovered powder are introduced into
a sealed container without kinetic energy
via the Soft Flow system. There the ultrasonic sieve and several level sensors arelocated with which the powder level canbe individually adjusted.
The powder is fluidized and the container
is additionally vibrated. The vibration homogenizes the fluid air and thus ensuresa more uniform mixing, and minimization of air bubbles, which results in a morehomogeneous powder cloud. This in turnhas a positive influence on the layer thickness distribution.

Long-term stable and precise
powder feeding
Whereas in conventional powder centersthe fluid air is directed to the outside andleads to dust or powder loss, it is still usedin the IPS container to build up pressure in
the container. The energy is used twice, soto speak. This slight overpressure replaces
the need of building up a vacuum to suckpowder into the injector or pump.

© J. Wagner

Optimum powder preparation
as a basis

The powder removal takes place at thebottom of the container; the powder quantity is controlled by a dosing valve. At theoutlet of the dosing valve, the powder isaccelerated and brought to the guns by airconveyance. By decoupling powder supply
and further transport, considerably more
powder can be conveyed over longer distances – 400 g/min at 30 meters are possible.
SFT works extremely precisely and remains constant for a long time, eliminating the disadvantage of the injector. Thedosing valve has a very simple design andsignificantly reduces maintenance compared to pumps.

Higher system availability
The IPS fresh powder system (Smart Boxer) can accommodate two powder boxes,
which reduces the risk of system downtime due to a shortage of powder. Powder deficiency is detected by weight sensors directly at the source, not in the working container.
The ability to work with two boxes, withthe system automatically changing fromempty to full box, significantly increases the available time interval for changing the box. This eliminates the need tostop the conveyor due to a lack of time
to change the box. The resulting coatingtime adds up to a significant productivity gain.
The feeding process to the guns is also
monitored by one sensor per gun. Thismeans that a malfunction is detected im-

mediately and not only by the quality control at the receiving station.

Color change in less than 10 minuteswith the highest quality standards
In the St. Margarethen facility of Liosaplast, a leading Swiss company in functional and decorative plastic coating, a modern, highly efficient, computer-controlledplant for pretreatment, liquid and powder
coating is located. The compact and flexible system configuration ensures shortthroughput times. A Power + Free hanging conveyor system transports the parts
through the system. The product carriers
allow component sizes of up to 3.2 × 2.0
× 0.8 meters and a weight of up to 300
kilograms.
An IPS system from Wagner was installedin April 2018 with the aim of significantly reducing color change time while maintaining consistently high coating and color change quality. After short commissioning and operator training, the color
change time could be reduced significantly – even with extreme color changes andthe highest quality requirements. „Today
we have an average of less than 10 minutes. Before the installation, it was 20 to
25 minutes,“ confirms Managing Director
Roger Gauderon.
In addition to a constant process flow
through automation, the Airblade and pulse flushing units used play a decisive role.
The operator can also change the intensity depending on the type of color changeand thus influence the times.Powder Coating I Fully automated coating centerhas also proven its worth in the coatingof different substrates, powder types andcolor shades.

© J. Wagner

8 months without sieve change

Automated color change and easy operation via a flexible touchscreen reduce the risk ofoperator errors that can quickly lead to rejects and re-cleaning.

The ultrasonic sieve makes a considerable contribution to increasing the coatingquality. In recent years, the technology
has improved to the extent that vibration generation through dynamic frequency optimization (Cool Sieve) generates astable process in which, for example, heatspots on the sieve with melting powder
are avoided.
The understanding of the dependenceof the sieving function on powder type,powder production, sieve mesh widthand sieving capacity could also be clarified further, so that the sieving process today functions reliably. However, the service life is often unsatisfactory. In the IPS
system, a powder throughput of 85 tons ineight months is possible without changing
the sieve. This effect was also confirmed
in enamel powder processing.
The powder is conveyed to the sieve bySoft Flow feeding without kinetic energy
and is cleaned automatically and without
contact. This eliminates the risk of mechanical damage such as cracks or changes insieve tension.

© J. Wagner

Ready for production 4.0

The fully integrated ultrasonic sieve enables a powder throughput of 85 tons in eight months
without changing the sieve. The powder is conveyed to the sieve without kinetic energy andcleaned automatically without contact. This eliminates the risk of mechanical damage such ascracks or changes in sieve tension.

Uniform layer thickness distribution
reduces powder consumption
Liosaplast states a better layer thickness
distribution after only a short period of
operation and estimates this to be 20 micrometers. The new SFT powder feeding
concept works in two directions: The
high-precision control of the powder dosing produces a very constant powder output, even over a long period of time. The
effect is supplemented by the lack of va18

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riation in powder output due to a fluctuating powder level, which has to be accepted in open systems due to the hydrostaticpressure of the powder column.
The IPS system is a physically closed system in which fluctuations in the powder
level do not alter the powder quantity. It
is therefore superior to conventional powder centers and produces a higher quality level in terms of layer thickness distribution. Thus the total powder consumption is reduced in the long run. The system

High system availability, fewer manual activities, simple operation, assured coatingquality, reduced wear and energy consumption all lead to lower production costs. In
addition, companies that coat many workpieces every day are ideally prepared withIPS for production 4.0: The coating centercan be connected to Wagner‘s Internet ofThings solution Coatify, which, for example, provides graphically enhanced live monitoring of key figures and an interface tothe service department. //Author
Michael Topp
Senior Produkt Portfolio Manager
J. Wagner GmbH, Markdorf
Tel. 07544 5051725
michael.topp@wagner-group.com
go.wagner-group.com/ips
www.wagner-group.com