Sand for special cases

The EWK GmbH from Eisenberg in North Palatinate manufactures a broad portfolio of refractory concrete, ramming mass, sprayed material and casting slip, dry vibration and plastic mass – all based on luting sand, which is fire-proof and said to have particularly good bonding properties. These materials are used, for example, in iron, steel and non-ferrous metal foundries, in the aluminum industries, in steel works and cement factories. The manufacturer fills the bulk material in paper and plastic bags. In order to enable their quick and, above all, precise stacking on pallets, EWK uses a BEUMER paletpac. Not only does the high-performance layer palletizer prove to be extremely robust in dusty production environments, it also allows ergonomic operation and meets the manufacturer’s high demands on energy-efficient process technology (Fig. 1).

Eisenberg is a very special place with one of the largest luting sand deposits worldwide (Fig. 2). Luting sand is a material with a relatively high proportion of clay, which agglutinates the individual quartz grains – hence the name. This kneadable raw material began forming about 30 million years ago from weathered sandstone, which accumulated and deposited in hollows and depressions. The characteristic feature of this decomposition product is its fire resistance. For this reason, this special raw material is so sought-after by the refractory industry and in foundry processes. “The luting sand we mine and process is said to be very clean and particularly adhesive due to its mineralogical and chemical composition,” describes Axel Deubert, Head of Maintenance at EWK GmbH (Fig. 3).

The company, previously called “Eisenberger Klebsandwerke“, has been family-owned since its foundation in 1903. Based on state-of-the-art technology, the company produces different refractory castables, neutral, basic and acid semi-plastic and dry-vibration mixes and, in addition, specific materials for repair and spraying works. “With special formulations, we can adapt our products to individual customer requirements,” says Axel Deubert. Moreover, EKW offers system solutions for the functional lining of the various melting and thermal treatment furnaces including periphery. About 160 employees are working at the main production site, worldwide about 400. EKW has subsidiaries in Italy, France, Slovenia, Brazil, Malaysia and Mexico, several participations and partner companies in Germany as well as numerous representations around the globe.

Reliable and quick palettizing solutions

The products reach the customers in most different ways. For example, they are filled directly into silo vehicles, in Big Bags – or in paper and plastic bags. The latter are stacked on palettes and wrapped with foil. “In recent years, we modernized our central packaging facility in order to meet the increased demands of the packaging technology”, says Deubert. These demands include transport safety, the display effect of the packed goods and the protection from weather influences in the case of outside storage. “However, reduced costs of energy and material consumption are also decisive. Our work is particularly energy intensive”, describes the Head of Maintenance. Therefore, EKW attaches great importance on efficient process technology. As a KMU, the manufacturer has voluntarily undertaken to certify the company according to ISO 50001. With this energy management system being consistently implemented, the energy demand can be reduced by up to 20 % and more.

To enable energy-efficient production, EKW, among other things, replaced the old shrink hood unit by a stretch hood plant. It was, furthermore, important to achieve a better and continuous stacking result. When searching for the suitable provider, the decision-makers found the robust and sustainable high-performance layer palletizer paletpac, which stacks bulk material bags on pallets - exactly layer by layer.

Making the right investment decisions

Beumer developed all plants and systems according to a holistic approach, the Total Value of Ownership, which is based on the economic evaluation of a product. Concretely, this means: how much can the operator earn with this solution? This comprises ecological aspects, such as energy-saving operation, as well as social factors, which include, for instance, ergonomic man-machine-interfaces. With this concept, users are able to describe the efficiency of their operational investments as a whole and, above all, more meaningfully. Not only do they determine their direct costs, but above all the “Total Value” of the solution to be delivered throughout the entire operational life.

The intralogistics provider delivers a plant with a palletizing capacity of 2500 bags per hour. With a packing height of 2400 mm, the plant stacks the bags on all common pallet sizes – including intermediate sizes, like pallets with the dimensions of 1400 x 1200 mm - and in all technically feasible packing patterns.

Very broad-based portfolio

Axel Deubert is walking through the central mixing plant. „We quarry the luting sand by means of wheel loaders and transport it to the silos. We create the various formulations from the raw material and other materials in the large-capacity mixers.” Here, all kinds of dry masses, mainly concretes, are mixed for diverse applications in foundries, steel works and other branches of industry (Fig. 4). The desired consistency is achieved within minutes. “Moreover, we produce mortar from fine luting sand, clay and other aggregates – about eight tons per hour”, explains Deubert.

EKW fills these dry masses into the paper and plastic bags via six nozzles. Up to 1200 bags with a weight of up to 25 kg are packed that way. This corresponds to an amount of about 30 t of bulk material per day and an annual output of about 50 000 t. With the filling process being completed, the plant closes the bag and makes it tip onto a conveyor belt, which transports it to the BEUMER paletpac (Fig. 5).

Quick and gentle palettizing

The bags are, quickly but carefully, positioned on the stacking table in the desired packing pattern by means of various clocked conveyor belts and rotating devices. Afterwards, the bags are deposited in layers on a Euro-pallet provided on a rotating device. Then, the employee sets the parameters for the desired stacking pattern using a multi-program. The BEUMER paletpac stacks the bags im Wechselverband – eight layers each, one Fünferverband per layer. Thus, the pallet reaches a total weight of about one ton. Due to the geometric accuracy of layer and stack formation, the stacks themselves are very stable and can be arranged one on top of the other allowing space-saving storage. The BEUMER paletpac 2500 can stack up to 2500 bags per hour. “As a rule, however, we only palletize about 2000 bags”, says Deubert. Moreover, employees can quickly retrofit the BEUMER plant for product changes.

The full pallets then reach the downstream-arranged packaging unit via roller track, where they are completely wrapped into a stretch hood film. It protects the different products from weather influences during storage and transport to the consumers or from wetness in case of outdoor storage. The maintenance costs of the BEUMER paletpac are very low. “Minor maintenance tasks can be carried out by the employees”, describes the maintenance manager.