ESD Corrugated Plastic Boxes Warping or Collapsing: Causes and How to Reorder

ESD corrugated plastic (danpla) boxes used in Vietnam factories that warp, collapse at the walls or split at the corners after a few months are usually loaded over 5 kg, stacked more than 4–5 full tiers, made from thin board, left in the sun or dragged across the floor. PRIMEAG recommends specifying 4 mm, 800 g/m² board, U-channel edging and riveted corner brackets; move heavy parts to molded PP crates.

Corrugated plastic (danpla) is a twin-wall hollow PP board that gets its stiffness from the rows of internal flutes. Once the flutes are crushed or the edges are left open, the box deteriorates very quickly.

1. ESD corrugated plastic boxes warp from overloading

PRIMEAG’s 350 × 160 × 200 mm box is rated for 5 kg. Fill it with screws, transformer cores or metal subassemblies and that limit is exceeded quickly: the base sags like a dish and boxes on sloped racks slide out of line.

2. Stacked too high, or left in full stacks too long

The 4–5 tier rating assumes all boxes are full and bear squarely on the corner brackets. Stack higher, or put a half-empty box on a full one, and the load shifts off-center: rivets pull out, brackets crack, walls collapse.

3. Thin board, dividers without edging

Boards sold as 4 mm danpla vary widely in grammage. PRIMEAG boxes use 800 g/m² board. Loose-cut dividers without edging press against the walls and push them outward.

4. Sunlight, hot-water washing, dragging

Left near a sunny door for long, PP board lacking UV stabilizer becomes brittle and the edging breaks. Washing tends to leave water trapped in the hollow flutes; wipe only with a damp cloth or IPA. Dragging across the floor wears the base edges, opens the flutes and sheds plastic particles.

5. Rising resistance

Black danpla is carbon-loaded throughout, so wiping does not remove its dissipative property. Higher readings usually come from oil, paper labels or ordinary tape covering the surface. Measure per ANSI/ESD STM11.11 on the inside surface, outside surface, edging and brackets: ESD plastic trays and crates achieve 10³–10⁹ Ω; PRIMEAG danpla boxes are specified at 10⁶–10⁹ Ω.

When to switch to molded PP crates

For parts over 5 kg per box, or boxes carried on trolleys between workshops, use a black ESD PP plastic crate 610 × 420 × 390 mm, 30 kg load, 5 tiers when full. Danpla costs about 50 % less and is made to the exact line dimensions. For components on the bench: ESD plastic tray 450 × 300 × 60 mm, 8 kg load. The three types are compared in ESD trays, crates or corrugated plastic boxes: which to choose.

What to specify when reordering danpla boxes

Getting started: inspect the boxes in use

Take the three worst-damaged boxes, weigh the contents, count the tiers, and see whether the edging, brackets or base failed. If the edging or brackets failed, replace those parts; if the base sags, move to thicker board or a molded crate. Order new boxes via the custom-size ESD corrugated plastic box page, from 200 pcs.

To find out whether your existing boxes are still in range, the PRIMEAG team can visit your plant in Ho Chi Minh City, Dong Nai or Binh Duong (Mon–Sat) to measure ESD resistance free of charge on all ESD materials in use, including items bought elsewhere, using a TR1800 meter with 5 lb electrodes, with no limit on measurement points and no purchase obligation; a PDF report is sent within 3–5 working days; readings are for reference only and do not replace audit records. How to divide compartments and label boxes for line feeding is covered in preventing mixed-up parts on the line with divided trays and labels.

Frequently asked questions

• How long do ESD corrugated plastic boxes last? — About 1–2 years depending on usage frequency, based on experience; the dissipative property does not wear off, failures are mainly in the edging and brackets, which can be replaced separately.
• Should we choose 3, 4 or 5 mm ESD danpla board? — 3 mm for light trays; 4 mm for most line-feeding boxes; 5 mm for boxes taller than 300 mm or loads over 5 kg.
• Can open ESD danpla boxes be taken outside the EPA? — Not recommended; outside the EPA you need discharge shielding: lidded boxes or shielding bags.