Companies use warehouses to store their product until the time it is shipped out to stores. To conserve space, various racking methods are used to fit large quantities of product in tight spaces. The techniques implemented may vary from warehouse to warehouse, depending on the amount of product and the space available for storage. The differing racking techniques are:
· Block Racking
· Frame Stacking
· Flow Rack
· Push Rack
· Drive Racking
· Single-Stack Racking
· Double-Stack Racking
Each racking strategy can generate more space for the warehouse staff to house larger quantities of product and to save on the space for future product arrival. The methods of racking are explained further:
A majority of warehouses use the block racking method. The pallets of stored product are put into block design or in lanes. The pallets can be stacked on top of one another, depending on the weight and height of each pallet load, the clearance of the warehouse, the condition of the pallet and the forklift capabilities to remove each pallet when needed.
When removing the pallets, the product is taken by forklift by removing the last pallet in is the first out design or what is known as (LIFO; last in, first out). This is the least costly technique of storage for warehouse staff. There are no racking techniques involved and no special requirements of the warehouse design.
Pallets are built together to form a frame for the stacking frame method. The frames can be repositioned in the warehouse if necessary and are built to be mobile. The frames are stacked which produces a nice method of storage when pallets are not stackable using the block method. Pallets are traditionally placed on top of each other, without too much concern of spillage since they are framed.
Companies use the stacking frame technique when warehouse space is scarce. The removal is completed by the LIFO method. When the LIFO method is not used in the racking process of either the stacking frame or the block stacking, honeycombing can occur. Honeycombing is when spaces are left that are empty and cannot be refilled until the whole lane is removed.
Pallet racking does provide procurement of the pallets in a safe enough manner to remove single pallets without disturbing the stack. Most warehouses use this method to store their product. It takes away the risk of honeycombing such as with use in the block stacking and stacking frame methods.
Once the pallet is removed from the space, another pallet may immediately be slipped into that slot. Single pallet racking is set up in a variety of ways. The bad side of the single stack racking solution is the issue of honeycombing. Without proper removal, this method can leave large spaces in the center of the aisle.
The double stack racking system is similar to the single stack racking style, with the exception that two racks are designed to sit together. The double racking method leaves the ability to honeycomb and a specialized forklift is needed for this method to work properly. The aisles required are reduced in number using this technique.
The drive rack creates available space in the warehouse similar to that of the double rack and leaves ample lanes for the forklift drivers to load and remove the pallets that are needed. While the forklift drivers have the lanes, often this leaves very little space for the forklift manoeuvring capabilities, which slows down the time of removal, and stacking pallets using this racking method. When removing the pallets, the LIFO principle is implemented due to the lack of space between aisles.
In warehouses that have a constant moving product line, the pallet flow racking method is suitable for their needs. A conveyor is used to flow product pallets along as they are needed and they must move in a first in, first out (FIFO) method. As the pallets move forward, the next pallet is automatically placed in that position. This method is best for those warehouses that have the higher flow-through of product but is one of the most expensive to put into place.
A carrier is used for the push back rack storage solution. The carrier moves along a rail that keeps things flowing nicely. The load is put into place by the carrier and continues to push other pallets further into the storage area. As loads are removed, they are taken using the LIFO method of removal. As the pallet is taken from the storage area, another pallet immediately takes its place. Each pallet is positioned to allow for easy removal using this method. Warehouses that require the first in, first out solution are not suitable for this type of racking method. The push back rack technique is a little costlier for the equipment but worth the cost when space is limited for forklift use.