A pallet flow-through rack, also known as a gravity flow rack, is a type of storage system used in warehouses and distribution centers to efficiently store and retrieve palletized goods. It's designed to maximize storage space while enabling a first-in, first-out (FIFO) inventory management system. This type of rack is particularly useful for perishable goods, time-sensitive items, or products with expiration dates.

The rack consists of multiple inclined lanes or tracks with rollers or wheels. These tracks are set at a downward angle, typically around 2% to 4% slope, allowing pallets to move by gravity from the loading end to the unloading end.

Pallets are loaded onto the higher end of the inclined tracks. As one pallet is removed from the unloading end, the next pallet automatically moves forward to take its place. This continuous flow of pallets ensures that the first pallet loaded will be the first one to be unloaded, following the FIFO principle.

The force of gravity propels the pallets along the tracks. The pallets move smoothly and gradually due to the downward slope and the rollers/wheels on the tracks.

At the unloading end, employees can easily access the palletized goods for picking or distribution. Since the pallets are presented at the front of the rack, it minimizes the need for employees to enter the rack itself, improving safety and efficiency.

This system ensures that older stock is used before newer stock, reducing the risk of product expiration or obsolescence.

Pallets are densely stored, making efficient use of warehouse space. This is particularly beneficial when dealing with high volumes of goods.

Pallet flow racks streamline the picking process as the pallets are presented at the front, reducing the time and effort needed to retrieve goods.

FIFO management helps in better inventory control, as products are automatically rotated without manual intervention.

This system is ideal for items with expiration dates, as it helps ensure older products are used first.

Pallet flow-through racks may involve higher initial costs due to their specialized design and components.

The rollers or wheels in the rack system require regular maintenance to ensure smooth pallet movement.

While this system is great for many types of goods, it might not be suitable for extremely heavy loads or goods with irregular shapes.

Changing the configuration of the rack system might require adjustments to the track angles and other components.