High bay warehouse

The high bay warehouse (HBW) has been a reliable pallet storage solution for decades. It is characterised by silo construction and heights ranging from 12 to 50 meters. These warehouses are mostly operated automatically using rail-bound storage and retrieval machines (SRM), though shuttles are also employed as storage vehicles. Conventional high bay warehouses are also available where narrow-aisle stackers handle storage and retrieval. Companies that choose to build and operate high bay warehouses benefit from high storage density since volume is optimally utilised vertically on a small footprint. Automatic operation reduces personnel costs while optimising the space used.

Based on the articles to be stored and the order structure, pallet high bay warehouses designed for single, double, or triple-deep storage using SRMs can store several hundred thousand pallets in a very confined space. The steel structure acts as a load-bearing substructure for the roof and the facade (silo design). In combination with stacker cranes, a system is created that is considered a machine and is associated with shorter depreciation periods.

While storing vertically instead of horizontally is an important decision criteria when it comes to installing a HBW, it's important to consider that infeed and outfeed conveyor systems must be installed in the prezone of such an automated warehouse, and the space requirements of these can be significant. Investment costs are high, while further expansion is challenging. Continuous maintenance costs should also be considered.

An alternative to conventional high bay warehouses are channel warehouses, where several storage units are stored one behind the other in the channels to save space and channel vehicles or shuttles take over storage and retrieval. The elimination of aisles results in a further increase in storage density. However, the fact that only the pallet placed at the very front of the storage compartment can be accessed has a restrictive effect. This means that only first in, first out (FIFO) or last in, first out (LIFO) storage is possible.

This restriction is eliminated by automated storage systems of the latest design, which combine the compactness of channel storage systems with the flexibility of shuttle storage systems. The solution - as simple as it is efficient - is trolleys on which the pallets are placed. These can be easily pushed to the side to form a temporary aisle that provides access to any desired storage location. Heights of between four and 40 meters can be realised, with a reduced space requirement of up to 45%.