The effect of slot-code optimisation on travel times in common unit-load warehouses

The main aim of this paper is to estimate material handling times reductions in one-block unit-load warehouse organised with an optimal slot-code allocation, rather than with a uniform pick/store locations distribution, while comparing single and dual-command cycles from a travel distance perspective; results are calculated through multiple what-if analysis based on random scenarios simulations assuming variable input/output positions and warehouse shapes. Simulations helped in the effective quantification of travel times reductions, gaining a result of extreme importance for those manufacturing, distribution and retailing companies which aim at both designing their warehouse and determining the right type and number of transportation resources. Because of currently used warehouse management systems (WMS), companies do not reckon so needful of existing literature relying on uniform pick/store distribution: this paper seems the first to address a precise estimation of material handling times when fast-movers items are more or less effectively placed nearby warehouses entrance.