14 Sep Warehouse Storage: Non-Palletised Racking Methods
Although many warehouse operations make use of pallets for their storage and handling, there are some products which are simply not appropriate for palletisation. Due to their size or required handling procedure, non-palletised storage systems are needed. Here’s an explanation of the types of non-palletised storage systems.
Small Item Storage Systems
One of the most popular choices for the storage of cases and individual items is shelving. For this system, the shelves are commonly arranged in long rows that are accessible via aisles – much like the layout with single-deep pallet racking. Various specifications for the shelves are available, but on average each shelf can support up to 200 kilograms of product. The use of sub-dividers helps to set out numerous locations for storing different SKUs on one shelf. Shelving is usually free-standing and accessible by pickers from ground level. However, they can also be constructed up to higher levels, depending on the goods that will be stored.
Carton Live Storage
Carton live storage is suitable for products such as cartons that have smooth bases so they can roll easily off the inclined rollers. Carton live storage saves a lot of space as it eliminates the need for walkways and guarantees FIFO stock rotation and improved picking speed. Due to the system mostly being used in order picking areas, a large number of different SKUs can be positioned in a small run of aisle. This results in a reduction in the time needed, bringing greater efficiency to the operation.
Carousels come in either vertical or horizontal styles. Each gives the opportunity to make good use of the available floor space. They are usually controlled by a computer. Vertical carousels are made up of shelves that are suspended between two chains that are controlled by electric motors, allowing them to rise and fall. This means that the product is always at the ideal ergonomic height for picking. With horizontal carousels the columns of shelves move left or right, rather than up and down. They tend to be used for slightly larger products than vertical carousels.
Smaller items can be stored in an automated storage and retrieval system known as a miniload. A miniload is implemented through a crane, with access to cartons or tote bins from shelving or racking on either side of it. Miniloads are best suited for slow-moving goods with wide product ranges. It is possible to adapt miniloads for higher throughput situations. For example, with numerous shuttles operating on different levels within an aisle, bringing the goods to a vertical lift at the end.
Long products can often prove difficult to store as the majority of racking systems are unable to accept them, especially where the racking system uprights are narrower than the product being stored. Long products such as steel rods, carpets and wooden boards therefore need alternative storage methods.
One method is vertical storage, where items are stored in a “toast-rack” fashion, upright between storage modules. Another is pigeon hole racking, where the pigeon holes extend away from the aisle far enough for the length of the product. Block storage is suitable for items such as wooden boards, which can be strapped together and then stored in block with wooden separators that allow them to be lifted from underneath.
Conveyor systems move products from one fixed point to another. Gravity conveyors tend to move goods short distances, using a chute. And powered conveyors – such as belt conveyors, similar to those you’d find at a supermarket till – are more appropriate for transferring products over longer distances.
Conveyor systems maintain a continuous level of movement within the warehouse, but they have a high initial capital cost.
If you would like some guidance in planning the best non-palletised racking system for your warehouse, our consultants can help. Call us on 020 8819 9071 or get in touch for a demonstration.