Reinventing the Pallet Rack

“If it ain’t broke, don’t fix it” isn’t always the best advice. There’s always room for improvement. Take the pallet rack, for example. In its original form, it was a simple but ingenious racking system that saved space in the workplace by allowing forklifts access to goods and materials stacked at height.

Over time, the selective pallet rack, as it came to be known, continued to be improved, but basically remained the same. Designed for easy access and visibility, the selective pallet rack can be described as a “what you see is what you get” system.

If there was a drawback to the selective racking system, it was that pallets could only be stacked on two sides of the rack with aisle access from each side. Since aisle widths had to be up to 12′ to enable lift trucks to maneuver, a lot of potentially useful space was lost. The introduction of the narrow aisle (NA) and very narrow aisle (VNA) forklifts reduced aisle space considerably, but reducing aisle widths wasn’t the ultimate solution. The pallet rack needed reinventing.

Drive-in and Drive-through Pallet Racks

Drive-in and Drive-through pallet racks are used for more high-density storage. Drive-in racks have only one entry/exit point, so of necessity are “last in, first out” (LIFO) systems. Drive-through (or drive-thru) racking systems have two entry points. Pallets placed on one side of the rack move to the other side as pallets placed earlier are removed. Called a “first in, first out” (FIFO) system, a drive-through system is better suited for storing materials that have a limited shelf life or expiration dates.

Push-Back Pallet Racks

The push-back pallet rack is a high density system that can stack materials up to six pallets deep in each bay. A simple gravity flow system causes pallets at the rear to come forward when the first pallet in the row is removed. When a pallet is loaded into the bay, the forklift operator “pushes back” the other pallets. Push-back pallet racks are LIFO systems.

Flow Racks

Flow racks, like push-back racks, are gravity fed. The difference is that in these systems, there is two-sided access. New pallets are placed at the high end of the angled bay. When a pallet is removed from the low end, the pallets behind it automatically roll forward. Flow racks are FIFO systems.

Compact Mobilized Pallet Racks

Large warehouses use compact mobilized pallet racks that can be stacked against each other when aisle space is not needed. When access to goods stored on a pallet rack is needed, the other racks are moved sideways to create an aisle for the forklift to enter.

No doubt the pallet rack will continue to be reinvented to accommodate the changing needs of the materials handling industry. With the aid of digital and robotics technologies, many advances have already been seen. Who knows? One of these days, we may see the arrival of the flying forklift to access goods stored on pallet racks hundreds of feet high.