A machine that leaves the factory in perfect condition can arrive with rust on its slideways, a cracked casting or a crate that the destination authority will not release. The usual causes are not dramatic: a skid that was too light for the lifting points, damp timber sealed inside a barrier bag, a missing ISPM 15 mark on one board, or a centre of gravity nobody marked.

This guide is for machinery makers, plant owners and traders who ship equipment, moulds, spare parts and other heavy goods out of Vietnam, Japan and the rest of Asia. It covers how to specify the crate or skid, how to keep moisture and corrosion out, which marks belong on the outside, and what to check before the crate is closed.

💬 Shipping a machine or heavy parts? Send us dimensions, weight, centre of gravity, lifting points and route, and we will arrange crating and packing with a suitable packer in Asia. Tell us what you are shipping.

Choose the packing form from the item and the route

Decide between an open skid, a framed crate and a closed sheathed case from the item’s weight, fragility and moisture sensitivity and from how it will be lifted and stowed.

FormWhat it isSuitsWatch for
Skid (base only)Timber or steel base the item is bolted toRobust machines, flat-rack or open-top shipmentsExposed to weather and handling damage
Framed crateBase plus open timber frameItems that need protection from impact but tolerate airMoisture and dust still reach the item
Sheathed caseBase and frame clad with plywood or boards, closedPrecision machines, electrical cabinets, long sea voyagesMust manage moisture inside
Case with barrier bagSheathed case with item sealed in a vapour barrier and desiccantCorrosion-sensitive machined surfacesBag must be sealed and desiccant sized correctly

The base carries everything. Design it for the item’s weight and footprint, for the forklift or crane that will lift it, and for how the load will be transferred to the container floor. The CTU Code advises that when a heavy package with a small footprint is shipped, the concentrated load should be transferred to the structural bottom girders of the container. Ask the packer to show how the skid spreads the load.

Fix the item to the base with bolts through its own mounting points where possible. Block and brace inside the crate so the item cannot move in any direction.

Wood in the crate: ISPM 15

Every solid-wood part of the crate, skid and internal blocking must be ISPM 15 treated and marked; plywood and other processed wood are exempt.

ISPM 15 lists crates, boxes, packing cases, dunnage and pallets as wood packaging material. Its exemptions include packaging made wholly of processed wood such as plywood, particle board, oriented strand board or veneer made with glue, heat or pressure. A crate with plywood sheathing on a solid timber base is still in scope for the timber.

Practical consequences for crates:

  • Every solid timber component needs treatment, and the crate needs the official mark. Annex 2 says that on a composite unit made of treated wood and processed wood, the mark may be placed on the processed-wood parts if that is where it is visible and large enough.
  • Internal blocking and bracing is wood packaging too. Off-cuts used as wedges must come from treated, marked timber.
  • Repairs at the packer’s yard follow the repair rules. Replaced parts must be treated and marked.

We explain treatments, the mark and the repair rules in detail in our guide to export pallets and ISPM 15. Confirm the destination country’s current rules before shipping.

Moisture and corrosion

Rust inside a closed crate comes mainly from moisture already in the timber, the item and the air at packing; dry the materials, protect machined surfaces and seal sensitive items in a barrier with desiccant sized for the job.

The CTU Code’s annex on condensation explains the mechanism clearly. It says the source of humidity in a closed unit is generally the cargo itself and, to some extent, timber bracings, pallets, porous packaging and moisture brought in when packing in rain or high humidity. It sets a corrosion threshold: a relative humidity of 40 % or more leads to an increasing risk of corrosion of ferrous metals. It advises that ferrous metal products, including machinery, be protected either by a suitable coating or by measures that keep the relative humidity in the unit reliably below that threshold.

It also gives a figure worth knowing. The moisture content of dry dunnage, pallets and packing material can be estimated at 12 % to 15 %, and with that moisture content the relative humidity inside a closed unit will establish itself at about 60 % to 75 %. The Code therefore recommends additional measures, such as active drying of the dunnage and packing material, or desiccants, in combination with a sealed plastic wrapping. It adds that if drying agents are used, the absorption capacity needed should be calculated.

A practical sequence for a machine:

  1. Clean and dry the machine. Remove coolant, swarf and fingerprints from machined surfaces.
  2. Protect bare metal. Apply a temporary corrosion preventive to slideways, spindles and other bare surfaces, or use volatile corrosion inhibitor (VCI) products where they suit the materials. Ask the maker of the preventive how it is removed at installation.
  3. Use dry timber. Ask the packer for timber that has been stored dry, and do not pack in the rain.
  4. Seal the barrier. For sensitive items, enclose the machine in a vapour barrier bag sealed around the base, with desiccant inside.
  5. Size the desiccant. Ask the packer or desiccant supplier to calculate the quantity from the bag volume, barrier material, route and duration, and record the calculation.
  6. Add an indicator. A humidity indicator card visible through a window lets the receiver check the inside before opening.

Cargo sweat on arrival is the other risk. The Code notes that cargo moved from a cold to a warm, humid climate may cause condensation on the still-cold goods when unpacked, which is particularly harmful to metal products and machinery. If the route ends in a hot, humid climate, plan the unpacking with the receiver.

💬 Worried about rust on a long voyage? We can review the packer’s moisture plan, barrier and desiccant calculation before the crate is closed, and photograph each stage for you. Ask us to check the packing.

Marks and documents on the outside

Mark the centre of gravity, lifting points and handling instructions with standard symbols, and put the case number, weights and dimensions where every handler can read them.

The CTU Code says that if the centre of gravity of the packed cargo cannot be kept within the recommended limits, it should be marked on the outside or the forwarder and carrier should be instructed. For a single crate, mark the centre of gravity and the sling or fork positions on the case itself, so crane and forklift drivers do not have to guess.

ISO 780:2015, Packaging — Distribution packaging — Graphical symbols for handling and storage of packages, specifies the graphical symbols used to convey handling instructions on distribution packages. ISO notes that the symbols should be used only when necessary and that the standard does not include instructions specific to dangerous goods. The CTU Code’s appendix on packaging marks reproduces the symbols most regularly used, including “fragile”, “this way up”, “keep away from rain”, “centre of gravity”, “use no forks”, “do not stack” and “sling here”. It advises placing the centre of gravity symbol on all six sides where possible, and at least on the four lateral sides. It adds that the symbols should preferably be black, and that red, orange or yellow should be avoided unless regional or national rules require them, to avoid confusion with dangerous goods labels.

A typical outside marking list:

  • consignee mark and case number, for example “1 of 4”;
  • gross and net weight, and dimensions;
  • centre of gravity and sling or fork positions;
  • handling symbols to ISO 780 as needed;
  • the ISPM 15 mark on the solid-wood parts;
  • any dangerous goods marks and labels required by the applicable dangerous goods regulations.

Match the case numbers, weights and dimensions to the packing list. Our export shipping documents checklist covers the documents that travel with the crate.

Inspect before you close the lid

Approve the packing at the open-crate stage, with photographs, because once the case is nailed shut nobody will open it until it arrives.

A short checklist for a packing inspection:

CheckWhat to look for
Item conditionClean, dry, protected surfaces; loose parts removed and packed separately
FixingBolted through mounting points; no movement when pushed
BlockingWood is treated and marked; wedges fixed, not just placed
Barrier and desiccantBag intact and sealed; desiccant quantity as calculated; indicator card fitted
BaseSkid size and runners as drawn; fork entry and sling points clear
MarksCentre of gravity, sling points, symbols, case number, ISPM 15 mark
DocumentsPacking list matches case number, weights and dimensions

If you are buying used machinery, the packing is part of the purchase. Our guides to inspecting used Japanese equipment before purchase and importing used Japanese machinery into Vietnam explain the steps before and after it.

Once crated, the case still has to be blocked and lashed inside the container or on a flat rack. See our guide to container loading and dunnage.

Frequently asked questions

1. Does a plywood crate need an ISPM 15 mark?
A crate made wholly of plywood or other processed wood is exempt. Most crates have solid-timber bases, battens or blocking, and those parts must be treated and marked.

2. How much desiccant should go in a crate?
It depends on the barrier volume and material, the route and the duration. The CTU Code says the absorption capacity needed should be calculated; ask the packer or desiccant supplier for the calculation.

3. Is VCI film better than a barrier bag with desiccant?
They work differently, and the right choice depends on the metals, the route and the duration. Ask the supplier of the corrosion protection which method suits your machine, and how it is removed at installation.

4. Who marks the centre of gravity?
Whoever knows it: usually the machine maker or the packer, from the drawing or by measurement. Mark it on the crate and state it on the packing list.

5. Can you pack machinery that we buy from another supplier?
Yes. We can arrange crating with a packer near the supplier’s site, inspect the packing and coordinate the shipment with the rest of your order.

Summary

Choose the packing form from the item and route, use treated and marked solid wood, control moisture with dry materials, protection and calculated desiccant, mark the centre of gravity and handling symbols, and inspect before closing.

Sunsho Trade is a trading company. For heavy goods and machinery we arrange packers in Vietnam, Japan and Asia, check the packing plan and materials, inspect the open crate, and coordinate documents and shipment. Our guide to exporting from Japan covers the flow when the machine starts in Japan.

💬 Ready to ship? See our industrial packaging and logistics materials service, or send us the machine details. For other plant equipment and supplies, start from industrial sourcing.

Sources

Checked on 27 October 2026.