How many units of a transport and storage container should be sampled per lot?

Answer: Eight below 500, thirteen to 2000, twenty above, drawn across pallets rather than one cavity's run.

Does a pressure drop test replace the rain test?

Answer: No. Pressure shows airtightness, rain shows the rim joint under standing water; a tight case can still take 2 g to 3 g.

Are nine wall thickness points enough?

Answer: Nine is the floor. A tenth near the gate is worth logging but stays out of the verdict, since gate areas run thick and lift the average.

Can the drop height be lowered for a known route?

Answer: 1.2 m matches a case slipping from waist height by hand. A pallet route can drop to 0.9 m, if the file names it.

Can the supplier's report replace incoming acceptance?

Answer: No, since the supplier controls sampling and gauges. Run a visual pass, 8 units on dimensions, 3 on pressure.

Transport and Storage Container Acceptance: Tests and Criteria

Quick answer: A transport and storage container is accepted in four groups — visual, dimensions and wall, seal and rain, drop and stacking. Each group has its own sample size and limit, so one critical defect stops the lot.

Which Inspection Groups a Transport and Storage Container Plan Needs
Incoming and Visual Checks You Can Settle on Arrival
Sampling for Dimensions and Wall Thickness
Seal Pressure Drop and Rain Test Judgement
Drop Stacking and Nonconformance Disposition
FAQ

1. Which Inspection Groups a Transport and Storage Container Plan Needs

Acceptance starts with grouping, not limits: four groups split by failure consequence, each with its own sample size and record sheet, and a lot failing one stays in quarantine.

Order matters too: visual, dimensions, seal, drop. A dropped case carries stress whitening, so later visual judgement has no baseline. Grade findings critical, major or minor.

Group	Checks	Instrument	Record
Visual	Packaging, colour, surface, latches	Colorimeter, force gauge	Defect position per unit
Dimensions	Inner size, wall, rim flatness	Caliper, ultrasonic gauge	Nine-point wall chart
Seal	Pressure drop, rim ingress	Differential gauge, scales	Pressure curve
Drop	Six faces, corner, edge, set	Test frame, load blocks	Photos and sizes

2. Incoming and Visual Checks You Can Settle on Arrival

Incoming work judges arrival condition only: packaging, paperwork, colour against the approved sample, surface, latch seating, plating. Six checks close the same day.

Transport and Storage Container: black case corner close-up, ribbed inner wall with segmented seam, black foam with a square cavity, rim line

Colour reads ΔE 1.5 or less against the approved sample, 1.0 between units of one lot. A scratch over 10 mm that catches a fingernail is major, and three minor marks on one face merge. First opening force must land between 60 N and 110 N; lower means the claw pops in transit. Plating takes 48 h of salt spray without red rust; the handle holds 50 kg for 10 min.

3. Sampling for Dimensions and Wall Thickness

Sampling a transport and storage container follows lot size: 8 units below 500, 13 up to 2000, 20 above, drawn across pallets so one cavity cannot dominate. Smaller lots are inspected in full.

Wall thickness is the check most often waved through, because it cannot be seen. Nominal is 3.5 mm and the thinnest of nine fixed points may not fall below 3.2 mm. One thin point fails the unit; two units thin at the same point send the lot to 20 samples. Inner size holds ±2 mm, rim flatness 1.0 mm, latch holes ±0.5 mm.

4. Seal Pressure Drop and Rain Test Judgement

Sealing is judged pressure first: inflate to 2 kPa, hold 60 s, and a drop of 0.5 kPa passes. Log ambient temperature too, since a 10 °C swing moves the reading by about 0.1 kPa.

Transport and Storage Container: black case open on pale grey, foam holding a drone body, controller and three batteries, full foam lid, two latches

Rain runs at 100 L/(m²·h) for 30 min, lid up, case tilted 15°, pooling water on the rim joint. Dry paper inside may gain no more than 1 g; hunting droplets misses seepage.

5. Drop Stacking and Nonconformance Disposition

Drop the loaded transport and storage container on base, lid, four sides, one corner and one edge — eight impacts from 1.2 m onto concrete. Dents pass; a through-wall crack fails, because it ends the seal.

Stacking imitates a warehouse: 350 kg on the lid at 40 °C for 24 h, remeasured an hour after unloading, residual set capped at 3 mm.

Test	Condition	Units	Pass criteria	Retest
Pressure drop	2 kPa, 60 s	3	0.5 kPa or less	Add 3
Rain	100 L/(m²·h), 30 min	3	1 g or less	Add 3, then reject
Drop	1.2 m, 8 impacts	2	No through crack	Reject lot
Stacking	350 kg, 40 °C, 24 h	2	3 mm or less	Add 2, then reject

A critical defect returns the lot, with a cause analysis inside three working days; a major defect doubles the sample; past 15% rework the lot goes to full inspection.

Conclusion

What makes a plan useful is not strict limits, but whether each group can be repeated and blamed on its own. Pin the verdict table to the acceptance form, and batch quality for every transport and storage container stops drifting.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.