High-density rack where each newly loaded pallet pushes the pallets already in the lane toward the back; lanes are several pallets deep and work last in, first out (LIFO).
Detailed Definition
Push-back rack stores pallets several deep on each level using nested carts or rollers on rails that slope slightly toward the aisle. When a forklift places a new pallet, it pushes the pallet already in the lane back one position. When the front pallet is removed, the ones behind roll forward by gravity. Every lane is loaded and unloaded from the same aisle, so the last pallet in is the first out. It gives more positions than selective rack in the same floor area, with less direct access.
How push-back rack works
Each lane has a set of carts that nest inside one another, or a bed of rollers. The forklift sets the first pallet on the top cart. The next pallet is set against the first and pushes it back, exposing a lower cart for the new load. The rails are inclined toward the aisle, so when the front pallet is picked the remaining pallets roll forward to the pick face. No lift truck has to enter the rack, unlike drive-in rack.
When push-back rack fits
- Several pallets of the same SKU per lane, where last in, first out is acceptable.
- Moderate to high pallet counts per SKU, but more SKUs than drive-in rack would handle well.
- Cold storage, where floor space is expensive.
It is a poor fit for strict first in, first out rotation; pallet flow rack is the usual alternative for that.
Pallet requirements and checks
Pallets must sit squarely on the carts, so the rack maker will specify acceptable pallet sizes, bottom deck design and weight. Broken bottom boards or protruding nails can snag carts or rollers. Inspect carts, rails and stops regularly, and keep the rated load on each lane within the capacity on the load plaque.
Related Glossary Terms
Frequently Asked Questions
Is push-back rack first in, first out?
No. Push-back rack is last in, first out, because pallets are loaded and unloaded from the same face of the lane. The last pallet placed sits at the front and is the first one picked. If your product needs first in, first out rotation, for example because of date codes, pallet flow rack loads from one aisle and picks from the other, which keeps the oldest pallet at the pick face.
How deep can push-back rack go?
Typical push-back systems hold two to five pallets per lane, and some manufacturers offer deeper lanes. Depth is limited by the cart or roller design, the slope, and how much product of one SKU you want in a single lane. Deeper lanes give more density but leave more pallets of the same SKU tied up behind the front pallet. Ask the rack manufacturer for the options and their rated capacities.