Palletizing in deep-freeze warehouses is one of the most demanding operations within the supply chain. Deep-freeze warehouse operators limit the time their employees are allowed to work in extremely low temperatures, which, however, increases the costs and complexity of palletizing in this environment.
Manufacturers and distributors of frozen food are therefore seeking to automate the storage and retrieval of pallets to increase their freezer capacity, boost throughput and efficiency, and minimize staff time. Integrating palletizing processes into the design of an ASRS (automated storage and retrieval system) allows for the optimization of fully automated, semi-automated, or manual palletizing of mixed pallets. Excerpts from a blog post by Alessandro Brusatori, Sales Manager, Integrated Solutions, Italy:
Even though demand for mixed pallets of frozen products is increasing, their volume is generally still lower than that of chilled or room-temperature stable foods. This smaller volume sometimes makes it difficult for cold storage operators to justify investments in fully automated palletizing and depalletizing solutions.
Another challenge for cold storage operators is, of course, the warehouse itself. Product integrity must be maintained during the palletizing process, and manual palletizing can be time-consuming and labor-intensive.
Layer picking
For operators with a consistent demand for mixed pallets, a layer picking and palletizing system integrated into the automated storage system can be an effective and practical solution. The collaboration between the storage system and the layer picking system, connected by automated conveyor belts, enables efficient, fully automated palletizing of mixed pallets without requiring personnel to enter the freezer room.
As with any palletizing solution, the feasibility of layer picking for a specific warehouse depends on customer order profiles and the quantity of actualmixed pallets required.
A. Brusatori
Even when a full layer isn't required for every order containing different items, it can be more efficient to adapt a pallet of mixed layers to order requirements by swapping out a few cartons than to assemble the entire pallet manually.
Swisslog has implemented layer picking solutions, integrating the Vectura pallet crane and the PowerStore pallet shuttle, in automated storage systems for several leading food manufacturers. ProMove conveyors transport pallets from the automated storage system to the layer picking system, where pallets of mixed layers are palletized. These are then transported from the freezer or back to the rack for storage, with the entire process controlled by SynQ software.
Sequencing
Layer picking, while highly efficient, is not suitable for every application, as it doesn't always readily support orders with a large number of different items. In such cases, Swisslog recommends lightweight shuttle systems like the CycloneCarrier or storage and retrieval machines for small parts, such as the "Tornado." These systems facilitate the storage and sequencing of cartons and optimize manual palletizing.
When cartons are needed for an order, the shuttle delivers them in the correct sequence to the order pickers, who work directly in front of the freezer. Due to the efficiency of the process, the products are not outside the freezer for excessively long periods, which could compromise their quality, and the order pickers can work in a significantly more ergonomic environment.
Photos: Swisslog
Height-adjustable load carriers at the picking station position the pallet or trolley at the correct height for each layer, eliminating the need for pickers to bend down to place cartons on the bottom layer or lift cartons to fill upper layers. The solution also allows for a smooth transition to fully automated palletizing at a later date, as robot-operated palletizing modules can replace the manual pickers.
For example, a system for Apetito, a European market leader in frozen ready meals, whose outdated cold storage warehouse needed modernization, included automatic depalletizing robots that supply cartons to an 18-aisle small parts warehouse. The warehouse is connected via a conveyor system to the picking and shipping areas, which in this case are located within the cold storage area.
Manual optimization
When warehouse space is limited or the number of mixed pallets doesn't justify automation, a picking tunnel can be an effective strategy for increasing manual palletizing productivity. In this approach, the floor level of selected aisles in an automated warehouse system is designed to allow for manual picking and palletizing. Conveyor belts replenish the picking tunnel as needed and remove completed pallets, eliminating the need for forklifts to assist with palletizing. Furthermore, removing forklifts from the freezer area improves the safety of the pickers' working environment.
Regardless of the chosen approach, software plays a crucial role in controlling warehousing, palletizing, and order fulfillment processes. Swisslog's SynQ software includes standard features for managing inventory and replenishing picking areas, and offers out-of-the-box support for palletizing mixed pallets.
Swisslog regularly collaborates with operators of cold storage facilities on the design and implementation of storage and palletizing solutions. This involves a preliminary analysis of site requirements, processes, and data on-site to deliver solutions that achieve the desired objectives in the most efficient and cost-effective way.
Author: Alessandro Brusatori, Sales Manager, Integrated Solutions, Italy
