To know what items have to be picked, a (pick) list is needed. These lists can be generated at a central location in the warehouse: a depot. It is also possible to receive this list electronically. The order pickers then possibly use a (mobile) terminal. If the pick lists are not send to the pickers electronically, they have to visit a central point, where the lists are printed or stored, to know what to pick. At this point, start-up tasks, like collecting or depositing a pick device and obtaining a pick list have to be performed. After the completion of the order, the goods have to be dropped off at a location in the warehouse, from where they will be send to the buyers.
central depot (left)
Usually this location is near the starting point, which would make the depot both the starting and the ending point of the order picking route. If the pickers can only start and end the picking route at one point, the depot from which they are collecting is a central depot. This depot can be situated anywhere in the warehouse, but a common location is at the front end of the aisles. (as reflected in the picture above)
Alternatively, terminals or RF scanners may be used in the warehouse. If this is the case and a conveyor is used, then the order picker is not bound to a central depot to drop off the picked orders. A conveyor transports goods through the warehouse and can be situated at the bottom or at the top of the racks, so that the belt is perpendicular to them. Since the conveyor only facilitates the order picking process in a way that the orders can be dropped off at any location on the conveyor, the options on the starting point of an order, which is independent of the ending point, also needs to be large in order to maximize the advantages of a decentral depot. A decentral starting point can be created by putting containers or boxes at every front end of an aisle. For example, in warehouses where orderpicking trucks are used and empty pick pallets (or other carriers) are available at the head of all aisles, orderpicking trucks can drop off full pallets at the front end of every aisle. The transport of full pallets is taken care of by faster equipment, such as conveyors and forklift trucks. The orderpickers may therefore finish a picking route in any aisle and proceed with a new route in the same aisle. Unfortunately, this is not an option in this site; it is only possible to choose a depot that is located centrally.