VLMs allow for very dense storage of small parts. The system’s ability to store and retrieve parts based on part number makes it a very efficient way to fill orders since the parts are delivered to the picker without the need to lookup locations or walk to a storage bin. This goods-to-man functionality and reasonably high retrieval speed has allowed these lifts to be used for distribution. Pick rates of over 100 lines/hour are not uncommon in a paired VLM environment once picklist automation is used to send orders directly to the lifts.
These carousels are the VLMs older cousin and still have a home in small parts distribution applications. The typical limitation with these units are height and the need for product size uniformity. Like VLMs these units can be paired for tandem picking and can have pick lists electronically sent to them for processing. Carousels are great up to about 18’ tall. Beyond that height it becomes more costly per cubic foot of storage than a VLM and proportionately slower with height. Combinations of carousels and VLMs are often the right solution when a large variety of part shapes and sizes are to be stored.