Now that we have examined the options available for pallet storage, we can turn our attention to order picking methods used for smaller units, such as individual boxes and loose products (products removed from boxes). In other words, picking and the different order picking methods.
The handling of these two types of units is based at all times on the need to help with the picking operations, meaning that for the most part they are used for preparing an order. As mentioned earlier, the picking operation is the warehouse operation with the greatest impact on the product cost.
Given the high cost of designing a picking operation, the first thing to analyse is how to move goods inside the facility in order to perform the task of selecting and removing units. In other words, the different types of picking practiced.
Different types of order prep or picking systems can be carried out in a warehouse according to what each product requires.
2. Classic light duty racking unit with walkways
3. Classic light duty racking unit on mobile bases
4. Racking units with pickers for loose boxes
5. Racking units with pickers for pallets
6. Pallet racking unit with turret-type forklift trucks
7. Live picking racking units
8. Live picking racking units with pick to light systems
9. Automated storage with miniload stacker crane
The first method is called person-to-goods, in which the operator carrying out the picking has to move around the warehouse to the position of each of the units to be picked for each of the lines requiring preparation.
The second method is called goods-to-person, in which the operator remains at the picking post and a machine moves the goods to that position, leaving them within the reach of the operator.
The third system is mixed. In a warehouse several storage systems with different operating principles can be put in place, each for a specific type of product. The image on the previous page shows different ways of carrying out the picking; all of these can be combined in the one warehouse.
Other systems can also be added to those already mentioned, such as vertical lift modules and horizontal carousels, such as those shown below, which will be discussed later in this article.
Vertical lift module system.
Storage system with horizontal carousels.