Calucem d.o.o., a member of Calucem Group based in Pula, Croatia, recently installed a completely new packaging line for the calcium aluminate cements that it produces. From filling to palletizing to stretch hooding, the line is essentially a turnkey installation by Beumer.
Sometimes referred to as high-alumina cement, calcium aluminate cements are resistant to high temperatures, chemical substances, and corrosion, explains Alfred Blažina, managing director of the cement plant. “Due to these properties,” he says, “it is used in the refractory industry, foundries, kilns, and combustion chambers, as well as in the building industry. We export our cement to more than 60 countries and are the world's number 2 supplier in this market.
"Up until now,” he continues, “we had used systems that were energy-intensive and high in maintenance. Calucem employees were responsible for changing the filling system from one cement mixture to another, which was never a trouble-free process. Depending on its composition, the material can be more fine or coarse. After a mixture change, large amounts of dust were generated, meaning material was lost. In search of a new solution and a suitable business partner, we were led to intralogistics expert BEUMER. Our product has very specific properties. We needed a supplier who we could develop a solution with for our particular product."
As a single-source provider for filling, palletizing, and packaging technologies, BEUMER Group supports its customers with sustainable solutions from a single source. "We installed the entire line,” says David Žargi, BEUMER representative for the Western Balkans and supervisor for the Pula cement plant. The specialists integrated the machines and systems using intelligent automation and linked them efficiently. Calucem needed compact systems that work efficiently, require little maintenance, and can be operated intuitively and easily by the employees, says Žargi.
"The cement industry normally uses turbine filling machines,” explains Stefan Bonenkamp, commissioning engineer at BEUMER. "They are particularly suitable for free-flowing products, such as cement." But in order to guarantee loss-free filling of varying compositions, BEUMER technicians installed a BEUMER fillpac filling machine with two spouts that operates according to the air-filling principle. This particular material can be finer than regular Portland cement, but it can also be pulverized or gritty.
Air-filling machines are frequently found in the food industry. They use a blower to fluidize the material that is to be filled, e.g. flour or cacao powder. These products can then be filled into bags, gently and precisely, without mechanical stress and at minimal air consumption, explains Bonenkamp. The product is filled according to the gross weight principle, i.e. the bags are weighed during the filling process. The BEUMER fillpac is therefore equipped with calibration-capable weighing equipment. This electronic weighing ensures exact filling degrees for the BEUMER fillpac. Special software supports permanent communication between the balance and the filling spout.
The product is then transferred through a rotary flap into the filling boiler. The ventilation of the boiler floor and of the upper part of the boiler can be regulated separately, which guarantees a continual product discharge. It creates a steady product flow with minimal compressed-air consumption. A special filling nozzle is equipped with a vent duct and an ejector that operates in cycles, extracting air from the bag during filling. After each filling process, the filling nozzle is cleaned by air pressure. This prevents the filled bag from being soiled. The quantity of the conveying air can be adjusted separately, depending on the product.
Calucem needed a compact and energy-saving solution for the fully automatic, efficient, and above all, fast palletizing of the bags. As a single-source supplier, BEUMER provided the fully automatic BEUMER robotpac, solving complex palletizing and de-palletizing challenges reliably and efficiently. The robotpac distinguishes itself through its remarkable precision and availability, as well as its gentle product handling. An ultrasound system ensures the precise measurement of the bags before they are palletised. This way, the position of the item can be exactly calculated and the bags can be placed precisely and gently. The precision guarantees an optimal stack configuration. This is not only representative of brand quality to the end customer; it also ensures that the stack remains stable during shipping and storage. The BEUMER robotpac palletizes up to 600 bags/hr. Two gripping tools are used: a suction gripper, which places a paper sheet on the pallet, and a fork gripper, which palletises the bags in the exact position on the carrier. "The flexibility of the BEUMER robotpac allows the customer to implement even complex processes with varying frame parameters," explains Žargi. “In addition, the robotic palletier is very robust, which ensures a secure operation even under extreme conditions. The drives work reliably, highly efficiently, and quietly. Which was an important precondition for the cement manufacturer.”
Roller conveyors transport the palletised bags to the packaging system, which uses a stretch hood system that draws protective plastic film down over the palletized bags, rather than wrapping them with stretch wrap.
"In order to keep the entire line compact and energy-efficient, we use the BEUMER stretch hood A at this point in the line, a new machine from our portfolio,” says Žargi. “The high-capacity packaging system from the stretch hood series was given a complete redesign. We analyzed and optimized different components during the development phase. We made it easier and safer for the user to operate this system compared to others.”
To facilitate the work for the maintenance personnel and to ensure high system availability, the new packaging system no longer needs a platform. Maintenance work, such as changing the blades or the sealing bars, is now handled at floor level. The operator opens a drawer, providing free access to blades and sealing bars. Additional benefits include the compact design and the resulting low height and small footprint.
A new film transport system, which is particularly gentle on the material, introduces the previously formed film hood into the system. On its way to the crimping and stretching unit, the sealing seam on the film hood cools down so that it can be crimped without losing time. Energy-consuming cooling units and long cooling times become superfluous. The pallets are packed in a shorter cycle time, which increases the packaging capacity at a lower consumption rate. Economical engines and a lower demand in compressed air optimise the energy balance. "The palletized goods are clearly visible through the smooth surface of the transparent, highly flexible film. Film packaging protects the goods against the environment and humidity. It also substantially improves transport safety,” says Žargi.
Beumer also used its newly developed operator panel with an optimized user interface and graphical navigation for operating the line. It’s an even more ergonomic workflow to the user. This easily understandable and intuitive interaction concept helps to define efficient working sequences. The soft-touch panel uses pictograms to guide the user through the machine control menus. The panel also gives the operator access to all required training programs and content. The systems are controlled by a Siemens SIMATIC S7-300.
"We have implemented this project hand in hand with BEUMER,” says Blazina. “The result is a packaging line that is customized to our specific requirements." The cement manufacturer was convinced of the excellent technical cooperation during the planning and development phase, as well as optimal adaptation of the systems. And because BEUMER provided everything from one single source, Calucem has only one contact for the entire system. This was also very important for Blažina. Because even these high-quality systems need maintenance and service. If necessary, BEUMER service personnel can visit the plant to check the system and perform any required adjustments.