Japanese High-tech High-bay Racking Store in Göteborg

MÖNCHENGLADBACH. Dagab is the wholesale division of the Swedish Axfood trading group, one of the four largest grocers in Sweden. Dagab delivers all chain stores in the southern part of Sweden from their distribution center in Göteborg. Until they restructured the warehouse, Dagab also operated a field warehouse 10 km away that was used to store most of the Göteborg dry goods at normal temperature. “The automatic high-bay narrow-aisle warehouse at our field warehouse was getting on in years and was no longer running efficiently. It also no longer gave us enough storage capacity in the long term. We asked our logistics partner for a convincing concept that would appreciably optimize all intralogistic processes and considerably lower costs,” says Christian Jensen, Operation Manager at Dagab in describing the project requirements. “DAIFUKU offered us the best modernization strategy for upgrading the facility.”

Consolidate two into one

DAIFUKU material handling experts drafted new logistics processes based on the DAIFUKU Quick Study^TM, a detailed analysis method that studies the flow of material and data at the warehouse locations and adapts them to the new requirements. The resulting concept contained the following reorganization measures: Steel high-bays still in good condition were dismantled at the field warehouse and reassembled in four aisles in a new

hall structure at the Göteborg distribution center. A new aisle was also added to the racking construction. DAIFUKU then equipped the resulting five aisles with new, 20m high storage and retrieval units and integrated the warehouse management system SattStore from their partner Consafe Logistics. The material handling experts from DAIFUKU also provided the corresponding conveyor technology to link the high-bay racking store with the respective storage and retrieval zones. To achieve maximum throughput rates, the logistics partner also integrated two tracked high-speed shuttle cars, so-called sorting transfer vehicles (STV), which, as a dual shuttle, transfer goods between the receiving point and the high-bay or the warehouse and the dispatch area. The conveyor technology at the existing Göteborg warehouse is housed next to the new construction. A single opening links the two buildings.

“By merging our distribution center and field warehouse, we save time and money. After all, our trucks now no longer have to shuttle back and forth between Göteborg and Juvel-Eriksberg,” Mr. Jensen says in explaining the advantages of the new intralogistics solution. “Another improvement worth mentioning is the fact that our new warehouse system only needs 2,400 m² of space to store 9,690 pallets. Compact storage was the basic prerequisite for combining the two storage facilities. In the end, the new solution had to offer enough reserves to compensate for our growing order volume despite the limited floor space in Göteborg.”

Faster in and faster out

The new flow of goods and data at Dagab is now organized as follows: In the incoming-goods area, pallets are transferred to the conveyor and run through an automatic scanner that checks the load dimensions. This is important since the pallets used by Dagab vary in height. After the warehouse management software has defined a storage location for the pallet in accordance with different optimization criteria, the pallet is transferred to one of the two STV units for placement. The sorting transfer vehicle is capable of travelling up to 160 meters per minute even when loaded. “In this project, the STV units are decisive for improving throughput. While at most only 75 retrieval operations were possible per hour at the field warehouse, Dagab now handles more than 150 pallets per hour in the modernized high-bay racking store,” reports Andreas Jablowski, Senior Engineer at DAIFUKU.

When retrieving goods from storage, the connected HOST system informs the warehouse management system of the corresponding request.  The latter passes the retrieval commands on to the control whereupon a fully-automatic storage and retrieval unit removes the corresponding pallet from the warehouse and transfers it to an STV. The STV transports the goods to the output zone roller conveyor which acts as an intermediate buffer for the pallets until order assembly. For the retrieval of rush orders DAIFUKU installed a separate track. Unlike the process in the regular output zone where pallets are picked exclusively in the stipulated order, Dagab employees have direct access to the urgently needed pallets.

Ready to run

Another project requirement was the maximization of storage capacity in the modernized high-bay racking store. For this reason, the DAIFUKU concept planned to make the most of local conditions and to set the foundation for the new hall lower than the existing warehouse. The difference in levels made it possible to utilize the third dimension, i.e. to extend the height of the warehouse. Consequently, the material handling experts had to compensate for a 1.5 meter difference in height at the point where the two halls connected. As a result, the STV units in the old part of the building run on concrete and in the new hall complex on an additionally integrated steel platform. To optimize the use of space, catwalks and walkways were also installed above the construction. This solution gave Dagab an additional 800 storage locations.

Convincing results

“The fact that DAIFUKU was able to provide us with all of the components from a single source was one of the main reasons why we decided to work with this vendor,” says Christian Jensen of Dagab in retrospect. “The positive results of the project confirm our selection: we have doubled the output of goods from 75 to up to 152 pallets. The high-bay racking system also provides us with extremely high stock availability.” By modernizing and reorganizing the distribution center, Dagab has noted the following improvements:

·       In an area measuring 2,400 m², the wholesaler now has 9,690 pallet positions.

·       Using the STV unit as a dual shuttle gives Dagab an extremely efficient and space-saving solution. The dual use of both STVs also provides system redundancy with a guaranteed future.

·       The modernized high-bay racking store optimally fulfills Dagab’s requirements in its flexibility, expandability and availability.