The last operation is the one that gets cut
What actually damages a casting in transit
Three things: parts rubbing against each other, parts rubbing against the carton, and moisture. Machined and coated surfaces are the most vulnerable; bare as-cast surfaces tolerate more than most buyers assume.
Layer separation and a tight pack solve the first two. Moisture needs a different answer, especially on sea freight where a container can cycle through condensation for weeks.
Specifying the pack
State the unit: parts per bag, bags per layer, layers per carton, cartons per pallet. State the separation material: paper interleaving, foam sheet, or moulded tray. State the pallet type and whether it must be heat treated for export.
Vague wording such as "export packing" is interpreted by each supplier differently, and the difference only shows up on arrival.
Moisture and coatings
For machined surfaces, a temporary protective coating plus a desiccant in a sealed bag is the usual combination. For coated parts, the risk is abrasion rather than corrosion, so the interleaving matters more than the desiccant.
If the part is leak tested with water, confirm it is dried before packing. Residual water in a sealed bag is worse than humid air.
FAQ
Does packaging belong in the quotation?
Yes. Ask for the packing specification and its cost to be stated, otherwise it becomes an unplanned adder or a quality dispute on arrival.
How should parts be separated?
Interleaving paper or foam between layers, or a moulded tray, so parts cannot rub. The requirement should be written, not left to the supplier default.
What about sea freight?
Sealed bags with desiccant for machined surfaces, and confirmation that parts are dry before packing. Container condensation over weeks is the main risk.
Do export pallets need treatment?
Wooden pallets for export normally need heat treatment or fumigation marking. Confirm the requirement for the destination country.
All figures above refer to standard product data sheets; final confirmation is subject to written quotation.