Medium-level order picking is always carried out on racking units, both those for general storage and those exclusively for picking. Mid-levels are located at heights no more than 3.5 to 4 metres.
Picking being done at different levels.
This order preparation system is a midpoint between low-level picking and high-level picking (the system on which it is based).
Preparing orders is always much faster when less time is lost going up and down between racking units. As a result, although the higher levels provide an advantage through making better use of the available volume, it is always useful to create a picking area at the mid-level or, in other words, place products with heavy rotation in the low to mid-levels of the racking unit and pick orders for these products only from that area.
Use of mid-level order preparation
There are two circumstances in which this strategy is recommended. The first is in warehouses or areas used exclusively for picking a high number of orders per working day. The second circumstance is in a distribution warehouse with a large number of orders concentrated into a limited number of SKUs. When designing a warehouse (or a storage area exclusively for picking) with a very large number of orders, the installation of this type of system provides the necessary speed of preparation.
Ideally, the area or warehouse with mid-level order preparation should be designed with manual picking racking units. Unloading and restocking occur in alternate shifts. Where so required by the speed of preparation, the system can be complemented with multiple low-level picking machines that will produce the best performance as long as they leave the aisle as little as possible.
Warehouse for an electronic components company.
When the speed required is very high, one machine can be used per picking aisle in the warehouse, ensuring unbeatable picking performance. In this case, a horizontal transport system must be placed in the aisle at the front of the racking units, using either conveyors or automated vehicles. With these conveyors or vehicles, individuals preparing orders only need to unload the completed orders onto these conveyors or vehicles, preventing any time from being lost.
In distribution warehouses with a large number of orders concentrated into a certain number of SKUs, these SKUs must be stored in the intermediate area of the facility. As a result, products can be picked using a mid-level picker, averting the significant loss of time that would occur if these orders were to be picked using high-level pickers. Furthermore, given that the cost of mid-level pickers is substantially lower than that of high-level pickers, the investment required is significantly lower.
Mechanical equipment for medium-level picking
The most suitable machines for picking at these levels are mid-level order pickers. These have already been described, in the section on "Handling Equipment".