Two key objectives in any good warehouse design are space efficiency and productivity. These objectives can come together nicely in an effectively planned push back racking system where we combine less travel between pick hits and provide maximum density by way of storing several pallets deep, but first of all – what is push back racking?
Push back racking is commercial and industrial racking with greater selectivity. All loads are stored and retrieved from the aisle and rest on a cart on a rail that slopes gently toward the front. When a new load is deposited into a lane, it ‘pushes back’ the one already at the face of the aisle and all those behind. Then, when that load is picked, the contents of the lane all move gently forward again, hence the term “push back rack”. Push back racking is ideally suited to business that stores skids of product SKU with a last in first out method.
In order to examine whether such a racking system is appropriate to your application you must first ask yourself a few simple questions.
- How many of your SKU’s typically maintain inventory levels of 5 to 15 pallet loads?
- Will the number of SKU’s maintaining this level of inventory be relatively constant?
A properly applied push back system provides both excellent density as well as selectivity. The objective once again is to minimize the amount of travel between pick hits and to store product as densely as possible. The workings of such a system are that the loads are placed on either carts or rails which sit slightly inclined within the racking structure. The lift truck operator will simply place the first load on a cart and when he then has a second identical load he deposits it in that same lane location; therefore, pushing the original load and its’ cart, up the inclined rails and then depositing the next load directly in front of the first. Push back systems are generally designed 2 to 5 pallets deep depending on heights, load weights, and the type of lift truck used to interface. The carts within the system nest beneath each other when not in use and typically provide the operator with some sort of signalization notifying him of the number of positions remaining within the lane. As with any racking application good utilization is critical. One must take a serious look at average inventory levels and assess both what is the optimal pallet depth required and how much of such a system is warranted. As with most any warehouse, good space efficiency and productivity requires a combination of 3 or more different systems.