Denesting isn’t a black art. But it is an art.
Ask anyone who has tried to automate tray feeding: a tray that runs perfectly on one line can refuse to run on another. Geometry, material and rigidity all decide whether a denesting solution that worked for the last pack will work for the next one. It can feel like a black art. It isn’t. But it is an art, and like any art it improves with practice.
Two hands, two technologies
Watch an operator denesting by hand and you see the whole problem. One hand holds the stack securely, but not so tightly that the other hand cannot work. The other hand picks a tray and places it, quickly but under control. Automating the job means replicating those two hands: a holding technology strong enough to support the stack yet compliant enough to release one tray, and a pick-and-place technology that lifts that tray cleanly and places it square.
No single clip or suction cup handles every tray the same way a human hand does. The answer is change parts: dedicated clips and pick tooling for each tray, interchangeable on one proven machine platform.
A test rig built like the real thing
To find the right setup for a tray, we built a fully adjustable test version of our mainline denester. It carries five standard clip designs, three pick-frame arrangements (straight, actuated and sidewall) and the most successful suction cups from the fifty-plus types we have trialled. It is HMI-operated, so every tray is tested at real production speed, not demonstration speed.
Every adjustable part carries a measurement scale. When a setup works, the numbers are recorded and fed straight into the design of the production machine’s tooling. Measure twice, cut once: parts made right first time, shorter lead times, and no late surprises.
What a trial tells you
A trial establishes the workable stack sizes for a tray, the clip type and positions that hold it, the pick type and cup positions that lift it cleanly, and how the tray hangs on the cups during transfer. It can also save money: a deep but flexible tray that runs on a straight pick never needs the actuated cylinders it would otherwise have been quoted with.
Hundreds of trays later
The test rig has now run hundreds of tray formats: fibre and board, foil, recycled plastic, barrier-lined paperboard, moulded pulp and conventional thermoformed trays. Every result is recorded, and the growing knowledge base makes the next difficult tray quicker to solve.
Got a difficult tray? Send it to PiP. We’ll run it, record the trial and show you exactly what happens. We’ll even send you the video.
Contact sales@pipautomation.com or call +44 (0)1706 369000 to book a test rig trial. You can see the rig, the materials it has run and real trial footage on our Tray Testing page.
Quick answers
How do you test whether a new tray can be automated?
We run the tray on a fully adjustable test version of our mainline denester, at real production speed. The trial establishes the workable stack sizes, the clip type and positions that hold the stack, and the pick tooling that lifts each tray cleanly. Every setting is measured and recorded.
Why does a tray that runs on one line fail on another?
Geometry, material and rigidity all decide how a tray separates from a stack. A small change in flange shape, moisture content or nesting depth changes how the stack holds together, which is why we test real production samples rather than ideal ones.
Which tray materials has the PiP test rig run?
Fibre and board, foil, recycled plastic, barrier-lined paperboard, moulded pulp and conventional thermoformed plastic trays. The rig has run hundreds of tray formats and every result is recorded in a growing knowledge base.
Got a difficult tray? Send it to PiP.
Prove the tray before you commit to the machine. Send us the packaging, give us the problem, and we’ll show you exactly how it runs.