Carton Flow Racking: Let Gravity Do the Walking
Direct answer: Carton flow racking loads at the rear and picks at the front on inclined rollers or skate wheels, so the next carton advances automatically. It suits medium-to-fast-moving cartons with many pick lines per day, and typically lifts picking productivity by cutting walk time rather than by moving faster.
The idea: load at the back, pick at the front
Carton flow racking is a gravity-fed system: operators load cartons or totes into inclined roller lanes from the replenishment aisle, and the stock flows forward to the picking face. The result is strict first-in, first-out rotation with no date-checking effort.
For distribution operations picking thousands of small lines a day, the gain is in the walk. Pickers stay at the front face while replenishers work the back, so the two jobs never block each other.
Lane design: separation, pitch and speed control
Each SKU should have its own lane; shared lanes destroy the FIFO logic. Lane width follows the carton, and full-width rollers suit flat cartons while skate-wheel sections suit smooth totes. Separators between cartons prevent jamming at the pick face.
For deep lanes or heavy cartons, speed controllers brake the flow so cartons arrive at the pick face gently. Lane depth is a trade-off: deeper lanes mean fewer replenishment trips but more floor per SKU.
How flow racks change the pick path
Because every pick face is at the front of a lane on an ergonomic angle, order pickers move along a single aisle instead of entering racking bays. Combined with pick-to-cart or put-wall methods downstream, this shortens travel per line significantly.
We plan flow rack projects from the SKU profile outward: carton size range, lines per day and replenishment frequency decide lane counts and levels - not the other way round.
Carton flow vs static shelving vs pallet racking
| Criterion | Carton flow racking | Static shelving | Pallet racking |
|---|---|---|---|
| Typical unit handled | Cartons and totes, 5–30 kg | Individual items | Full pallets, 500–1,200 kg |
| Picking lines per hour | Highest of the three — the next carton rolls to the pick face | Low; picker walks the aisle | Low; pallets are replenishment only |
| SKU count it suits | Medium to high, fast movers | Very high, slow movers | Low to medium |
| Floor space per pick face | Smallest — lanes are stacked 2–5 levels deep | Largest | Largest |
| Stock rotation | FIFO by design (load rear, pick front) | Manual FIFO | FIFO within a bay |
| Replenishment access | Rear aisle or rear-load level required | Same aisle as picking | Forklift aisle |
| Capital cost per position | Highest of the three | Lowest | Medium |
FAQ
What is the difference between carton flow and pallet flow racking?
Carton flow handles cartons and totes by hand at picking level; pallet flow moves full pallets by forklift on heavier roller lanes with brakes. The FIFO principle is the same, the load class is not.
Can flow racks store boxes of different sizes?
Yes, within the lane design range. Lane width and separator positions are set for a carton envelope; a SKU whose carton changes size seasonally should be assigned to an adjustable-lane section.
Do gravity lanes need maintenance?
Little, but not zero: rollers and bearings should be checked for flat spots, separators kept aligned and lanes kept clear of damaged cartons that wedge and block the flow.
All figures above refer to standard product data sheets; final confirmation is subject to written quotation.