Improving Order-Picking Response Time at Ankor's Warehouse

Ankor is a wholesaler of tools and garden equipment, carrying such well-known brands as Skandia. Its warehouse is under continuous pressure to improve its efficiency while it is confronted with several specific requirements in its order picking, like the requirement to retrieve heavy products first to prevent damage to other, breakable products. Our research goal was to determine a good combination of policies for storage assignment (assigning products to storage locations) and routing (determining the sequence in which to retrieve products from storage to meet customer demand) for Ankor's situation. We adapted existing solution techniques for this problem, overcoming the special characteristics of Ankor's operations. With these adapted techniques, we cut the average route length in the order-picking operation by 31 percent. As a result of our study, Ankor implemented a new storage and routing strategy. The study also showed further improvement potentials in the picking process, which Ankor adopted as well. All improvements led to a reduction in the number of order pickers of more than 25 percent.

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