Beumer Corporation, based in Branchburg, NJ, USA, installed a complete packaging line for various types of cement for Titan America in 2008. When Beumer received the contract for the installation of a complete packaging line at the company’s Pennsuco plant in Medley, Florida it included a Roto-Packer supplied by Haver & Boecker, the high-capacity bag palletiser Beumer paletpac® 5000 as well as Beumer’s stretch hood® M-system for the efficient film packaging of full pallets.
One of the challenges in the design of this packaging line lay in the handling of different bag and pallet sizes. At the same time, additional protection against dirt, moisture and transport damage as well as high load stability and the optimised use of warehouse space were to be achieved.
Around 300,000t of varying types of cement leave the Florida plant every year. In view of their different materials and formats, the entire packaging installation was designed to be flexible in its handling. Titan America also expected the complete installation to be operated with virtually no manual supervision.
Varying pallet heights and sizes
Since the installation of the complete packaging line, up to 3600 bags are being filled, palletised and packaged every hour. Given Titan America’s range of cement including Portland cement at a bag weight of 94lb, masonry cement at 70lb/bag, and stucco cement weighing in at around 8lb, Beumer recommended the installation of it high-capacity paletpac 5000 palletiser. Handling stack heights of up to 2400mm, the flexible paletpac can manage all common pallet sizes and desired packing patterns automatically.
Choosing between different bag and pallet sizes is managed by quick adaptations to the operating parameters in a multiple-application for all packing patterns. To keep friction to a minimum, Beumer covers the layer forming plates with a PTFE coating, allowing the cement bags to glide smoothly during layering, without rolling or loss of shape. The complete installation is driven by electricity alone, without any pneumatic or hydraulic components that would be susceptible to malfunctions caused by the amount of dust produced when handling cement.
The Beumer Group has put great emphasis on stack stability and stack accuracy in the design of the paletpac equipment. The bags of cement are stacked in individual layers on wooden pallets. Each layer is pressed from below against the closed layer forming plates, which expels any remaining air from the bags and adds considerably to the stability of the stack. The finished full pallet is conveyed by a heavy-duty pallet roller conveyor. The sizable pallet storage space at its end, allowing two finished pallets to be stored side by side, enables forklift drivers to pick up two pallets at a time for transport to the warehouse during peak operations. Beumer claims that his solution reduces forklift traffic by 50 per cent.
Excellent stacking stability with Stretch hood
As soon as the finished pallet reaches the Beumer stretch hood installation, the size of the product and the necessary amount of packaging film is determined by automatic scanning. The flexible film hood is pulled over the complete stack, maintaining extreme tension in both the horizontal and the vertical direction. This bi-axial stretching protects the vertical stretch of the film beyond the cut-off limit of 15 per cent.
The resulting understretch of the film hood ensures that tension is retained in the film and the desired constricting force is achieved. Immediately before the end of the stretching process, the film is kept in place by applying the film press units, while horizontal tension is reduced by guiding the film underneath the pallet. With this approach, the film hood is secured into place through the under stretch beneath the pallet. This stretch hood technology solution ensures excellent stack stability and protection against weather influence (UV rays, rain, dust, etc) even after repeated handling of the pallet, says Beumer.
Compared with conventional packaging methods like stretch wrapping and shrink hooding, the Beumer stretch hood method combines the advantages of both systems, while simultanously eliminating their shortcomings.
The result is a high-capacity packaging machine that boasts excellent display characteristics, five-sided product protection, elimination of laminates, protection against theft, minimised packaging costs and increased output capacities.
The Beumer packaging line at Titan America was adapted and designed to the specific needs of the client. It allows the option of additional pallet loads to be inserted between the palletiser and the packaging machine, thus enabling stacks palletised elsewhere to be integrated into the packaging process.
The system is controlled by Allen-Bradley PLCs equipped with graphic displays. All control devices, including proximity switches and photo-cells are selected for dusty heavy-duty industrial use and connected via AS-I bus systems to the PLCs.
Storage and shipping
The finished pallet loads leaving the stretch hood machine are transferred on a series of roller conveyors to a doubling roller conveyor that is fed at two points by a transverse shuttle cart. This brings the two
pallets together side-by-side, thus forming a single pick-up for the fork-truck consisting of two pallet loads. As a result, the number of trips to the warehouse or for truck loading is cut in half.
The double pallet handling capability not only reduces travel time, but it further saves time by allowing truck loading from just one side of the vehicle. This results in faster movement of trucks through the packhouse loading area.
Titan America holds the finished pallet stacks, well protected by stretch hood film, in warehouse storage in a two-stack high arrangement.
Article first published in International Cement Review, October 2010
