Absorbing quantities of high-color residual powder

The new powder coating plant was supplemented by a vacuum cleaner adapted to the specific application. The powerful suction unit, which is based on a standard model, is equally suitable for cleaning the floor and for extracting the filters. Big bags ensure a high volume.

Color strength is a necessary property of those powders with which, above all, highly stressed components are coated. This property is unpleasant if the powders do not adhere to these components, but rather get into the environment of the coating equipment. In practice, however, this cannot be avoided. This is where powerful vacuum cleaners are needed. These are also needed to remove the residual dust from the filter systems for disposal. Numerous companies use Ruwac suction units for this task. Among them is Coatinq GmbH in Castrop-Rauxel. It is part of the Zinq Group, a service provider offering galvanizing for permanent corrosion protection treatment at 45 locations in five countries. The group employs around 1,700 people and 80 trainees and says it is the market leader in the hot-dip galvanizing of steel components. At six locations - three of which are located in Germany - powder coating is also part of the service portfolio. Coatinq coats a wide variety of components for numerous customers and diverse industrial sectors. Plant manager Michael Spaan explains: "We are a classic contract coater, coating profiles as well as fence elements, containers and components for mechanical engineering - and on a large scale. We process around 300 tons of powder coatings per year." The color spectrum processed on the new continuous line, which will not be commissioned until 2021, is correspondingly colorful. For this reason, there are numerous color changes and, as a result, large quantities of residual powder that have to be vacuumed up and recycled.

Numerous colors in contract coating

In this work, high demands are placed not only on coating quality, but also on cleanliness in the plant and an orderly flow of materials to the end of the process chain. For this reason, those responsible planned the acquisition of a powerful vacuum cleaner that can take over floor cleaning, but with which the operator can also vacuum out and thus empty the filter boxes of the coating system. The impetus for the purchase of a Ruwac big bag system came from a presentation by Ruwac sales manager Klaus Gazawi at an online surface technology symposium. He presented a similar system in operation at an agricultural machinery manufacturer - with fewer color changes, because they mainly coat in the house color "seed green", but also with a high demand for quality, cleanliness and sustainability. An important factor from Coatinq's point of view was and still is the great flexibility when it comes to the choice of filling containers. "We can use different pallet sizes and big bags up to one cubic meter in volume and one ton in weight," says Michael Spaan.

Large reach, universal use

The frame of the plant was so generously dimensioned that even the largest Big-Bags bulge out when fully filled and can be removed without any problems. In the third dimension, the suction unit is inevitably also large, because the powder residues sucked in first flow through the filter unit and are then bagged by gravity in the big bag. The filter unit consists of a combination of filters of dust classes M (pre-separator) and H (main filter). This ensures that even the smallest dusts, which may be hazardous to health, are reliably retained with a maximum permeability of 0.005 percent. The vacuum cleaner is designed and approved for use in dust Ex zone 22. Drive and silo stations are housed in separate units, but in a common chassis. The 20-meter suction hose creates the prerequisite that the suction station - although mobile - can also be used as a stationary unit in practice. With the hose and the appropriate suction tools, operators can reach both the filter boxes directly at the coating plant and the storage and staging area for the big bags filled with disposal material. Another practical detail: Ruwac has designed an extended manual cleaning system for the filters for this type of plant. The operator can operate it from the ground, even though the filter is placed at some height above the big bag. Equally practical is that the big bags, for which a useful secondary use has been found here, each rest on a pallet. This makes them very easy to exchange and transport by forklift truck. From Ruwac's point of view, the mobile (large-scale) suction system for Coatinq is a concept that has proven itself primarily in powder coating and is just as suitable for large-scale floor cleaning as it is for vacuuming out filter boxes, for example. For the user, the system offers various advantages: it creates the prerequisite for simple, orderly, cost-effective and efficient re-logistics; existing containers can be used for this purpose.

Ruwac Industriesauger GmbH www.ruwac.com

Coatinq Castrop-Rauxel GmbH www.coatinq.zinq.com