Flow rack (FIFO): how do you supply material on a first-in-first-out basis?
A flow rack moves bins by gravity along inclined tracks from the loading side to the picking side. Whatever goes in first comes out first - that is FIFO. Loading and picking are separated, which makes it ideal for kanban and assembly supply with a constant flow of parts.
View flow racksHow does a flow rack work?
A flow rack is built from inclined lanes with roller or wheel tracks. Bins are loaded on the higher loading side and slide by gravity down to the lower picking side. The bin loaded first reaches the picking face first - that is the FIFO principle (first in, first out).
Because the lanes are inclined, gaps close automatically: when a bin is taken from the front, the next one rolls into the picking position. The incline sits in a low degree range depending on load and bin type, so bins travel in a controlled way and not too fast.
Flow rack versus static shelving - what is the difference?
In static shelving you load and pick from the same side, often on a LIFO pattern (last in, first out). A flow rack separates both sides and enforces FIFO. The table below shows the key differences.
| Feature | Flow rack | Static shelving |
|---|---|---|
| Material flow | FIFO by gravity | manual, often LIFO |
| Sides | loading and picking separated | single access side |
| Level | inclined roller or wheel track | level static shelf |
| Use | kanban, assembly line, picking | storage, changing items |
| Access | oldest bin always at front | any reach into the shelf |
For pure storage of changing items, a static shelf stays more flexible. For paced replenishment of identical parts, the flow rack plays to its strengths.
What matters when sizing a flow rack?
Three figures drive the sizing: capacity per lane, the incline angle of the tracks and the bin or carton size. They interact - bin weight and base decide which incline runs cleanly and how many bins a lane can hold.
Number of bins that fit one behind the other in a lane - it sets the range before refilling.
Choose it to suit bin weight and base so bins roll on safely and not too fast.
Match bin or carton dimensions to lane width and roller or wheel pitch.
Roller tracks carry heavier loads over a wide contact, while wheel rails are lighter and more flexible for small bins. For the right mix of lane count, incline and track type, an expert consultation based on your part range and cycle time helps.
Frequently asked questions
What does FIFO mean on a flow rack?
FIFO stands for first in, first out: the bin loaded first is picked first. The inclined tracks carry it by gravity to the picking side, so the oldest stock is always at the front.
What is a flow rack especially suited to?
Paced replenishment of identical parts: kanban, assembly lines and picking. The separated sides allow uninterrupted refilling at the back while picking continues at the front.
Does a flow rack need a drive?
No. Bins move by gravity alone on the inclined roller or wheel tracks. No drive is needed, only the correct incline angle.
Flow racks for kanban and assembly supply
FIFO by gravity, separated loading and picking sides, matched to bin, load and cycle time.
FIFO-safe
Inclined tracks enforce use of the oldest stock first.
Reviewed
Content reviewed by workplace specialists.
Right-sized
Lane count, incline and track type to your part range.
Expert advice
Personal advice on material supply.