An automation project usually starts with the process and the equipment, and the container is assumed to be fine because it has worked for years manually. Sometimes it is. Where it is not, the discovery happens at commissioning, when the container is the one thing that cannot be changed quickly. A short assessment before the equipment order settles it, and it takes an afternoon.
Measure the fleet, not the drawing
Take twenty containers at random from the fleet, including some of the oldest, and measure footprint, height and base flatness. The drawing describes what was ordered; the fleet describes what will run. Where the two differ – and after a year of service they usually do – the fleet is the one the equipment will meet. The spread across those twenty measurements is the number the automation needs.
Four things the equipment cares about
Footprint consistency, because the machine works to a fixed envelope. Base flatness and stiffness, because that decides whether the box spans supports and whether it seals or reads. Wall stiffness at the handling height, because that decides whether a gripper can hold it. And identification, because something has to tell the system what it is looking at. Four measurements, and none of them appear on a standard packaging drawing.
What good enough looks like
Ask the equipment supplier for the tolerance their machine needs rather than deciding for yourself – a conveyor tolerates more than a gripper, and a gripper tolerates more than an ASRS slot. Compare that number against the measured spread. Where the spread fits inside it with margin, the container carries over. Where it does not, either the container has to change or the machine has to be specified more loosely, and the first is usually cheaper.
The empty case again
Most automated systems handle empties as well as fulls, and empties behave differently: lighter, sometimes nested, sometimes less stable. Where an assessment only tests loaded containers, the empty case is the one that surprises. Testing both is a small addition and it catches the single most common commissioning problem. The dimensional version of this is in height tolerance in AMR handling.
Service condition, not new condition
A container that has been washed, stacked and handled for a year is not the container that was delivered. Its base is less flat, its walls are less square, and its dimensions have drifted. Where an assessment is done on new containers – which is the easy thing to do – it will overstate how well the fleet will run. Using the oldest containers available is the more honest test, and it is not harder.
What to do with the answer
Where the container passes, specify it properly: give the equipment supplier the measured spread rather than the drawing, so the machine is built for the real fleet. Where it fails, either sort the fleet – keep the in-tolerance containers on automated lanes and move the rest elsewhere – or buy new containers to a stated tolerance. Sorting is tedious and cheap; buying is clean and costs more; both work and neither is a disaster if discovered early.
The cost of not doing it
Commissioning delays, a rate that never reaches the quoted figure, and a modification programme that costs more than the assessment would have. Where the container is the problem, the symptom is intermittent faults that nobody can attribute, which is the most expensive kind of fault to chase. An afternoon with a tape measure and a straight edge prevents most of it.