A moulded wood pallet press forms a complete pallet in a single operation by compressing resin-coated wood particles or fibers in a heated steel mould. The pallet leaves the press as one piece without nails, with its fork openings and feet already molded in. Presses for this job are large hydraulic machines, and the plant around them (particle preparation, drying, blending and finishing) is far bigger than the press itself.
How the process works
Moulded wood pallets, also known as presswood or compressed wood pallets, are made from wood residues rather than from sawn boards. The pallet type itself, its load ratings and its market position are described in presswood (moulded wood) pallets. This page covers the machinery side.
The basic principle is that a mat of resinated particles is compressed in a mould at high temperature. Heat and pressure densify the wood, activate the thermosetting binder and set the pallet shape. According to published process descriptions, industrial presses commonly apply forces ranging from several hundred up to around 1,000 tonnes, with mould temperatures above 150°C. The exact values depend on the pallet size, wall thickness and resin system.
Early patents in this field describe pallets molded from matted wood flakes, showing that flake-based molding has been developed since at least the early 1980s. Today the products differ by manufacturer: some use finer fibers or particles, others flakes, and the surface and rib design vary.
Plant layout step by step
A complete line includes these stages:
- Raw material intake: wood residues such as sawdust, shavings, chips and sometimes cleaned recycled wood, stored in bunkers or silos.
- Size reduction and screening: hammer mills or flakers reduce material to a controlled particle size; screens remove oversize and fines. Metal, stones and plastics must be removed here to protect the mould.
- Drying: a rotary or flash dryer brings moisture to a precise level. Moisture matters because the resin must cure and water must escape as steam.
- Blending: resin, wax and sometimes fire-retardant or fungicide are applied in a blender.
- Forming: the mixture is metered into the mould cavity, often by a weighing and distribution station that sets how much material goes to each part of the pallet.
- Hot pressing: the mould closes under pressure and heat, and the resin cures. Cycle times are measured in minutes, not seconds.
- Demolding, cooling and trimming: pallets are removed, edges trimmed, and the pallets stacked for conditioning. Moisture re-equilibrates and mechanical properties stabilize.
- Testing and packing: weight, dimensions, deflection and surface are checked, and sampled pallets undergo load testing.
Binders and additives
Typical binders are urea-formaldehyde or polymeric MDI (pMDI, an isocyanate resin), sometimes with wax for water repellence and with additives such as fire retardants. The choice affects emissions, moisture resistance, cure time and cost. Isocyanate binders produce formaldehyde-free products but need careful handling and moisture control; formaldehyde-based binders are cheaper but require attention to emission limits and market requirements.
Press and mould design
The mould is the most specialized and expensive part of the line. It must withstand repeated pressure and heating cycles, distribute heat evenly, vent steam and release the pallet cleanly. Key design features:
| Element | Why it matters |
|---|---|
| Heating system (thermal oil, steam or electric) | Uniform temperature across the cavity affects cure and strength |
| Rib and foot geometry | Sets stiffness, nesting behavior and fork-opening dimensions |
| Venting | Steam escape prevents blisters and internal voids |
| Draft angles | Allow ejection without damage |
| Surface finish | Affects release and the look of the pallet |
A different pallet size or design requires a different mould, so product range is a major cost and lead-time factor. Changing models in a plant normally means a mould change, which takes hours and needs lifting equipment.
Capacity and investment scale
Capacity is set by cycle time, cavities per press and the availability of the upstream equipment. Because cure time is longer than the time needed to open and close the press, plants usually raise output by running multiple presses or multi-cavity molds rather than speeding up one cycle. Exact output figures vary widely between suppliers and are not standardized, so buyers should request performance guarantees tied to a specified pallet design and moisture content.
Moulded pallet plants are among the most capital-intensive projects in the pallet sector. They include the press, hydraulics, molds, dryer, resin system, dust extraction, fire protection and often a boiler or burner using wood residue as fuel. Because of this scale, they are usually built to serve a defined market, such as export pallets, automotive logistics or one-way shipping, and rely on guaranteed supply of cheap wood residues. Compared with nailed pallets, which require only saws and nailing machines, as described in the pallet machinery overview, the barrier to entry is much higher.
Standards and regulatory aspects
Wood packaging made entirely of processed wood material such as plywood, particleboard or OSB is exempt from ISPM 15 treatment, and moulded wood pallets are generally handled in this category, which is why they are popular for export; the exemption logic is explained in ISPM 15 exemptions. Importing countries should still be checked for specific rules, since a pallet that combines pressed wood with solid-wood parts does not qualify.
Producers should also test their pallets according to recognized methods, since deflection and racking behavior differ from those of nailed wooden pallets. See pallet testing standards for ISO 8611 and other test methods.
Frequently asked questions
How much pressure does a moulded pallet press use?
Industrial presses are described as applying several hundred up to about 1,000 tonnes of force, at mould temperatures above 150°C. The actual value depends on the pallet design and the resin used.
Why are moulded pallets nestable?
The pallet is formed in one piece with tapered feet and walls, so one pallet can sit inside another with little space wasted. This reduces storage and return-trip volume.
Can the same press make different pallet sizes?
Only by changing the mould. The press frame must be large enough for the biggest mould, but each pallet design requires its own tool.
Why do plants use wood residues instead of sawn lumber?
Particle and fiber processes work with low-value material, and cost per pallet depends heavily on cheap, consistent raw material. Residues must be clean and dry, and metal and plastic contaminants must be removed.
Sources
- The manufacture of presswood pallets — Racklify Encyclopedia
- Pallets molded from matted wood flakes (US Patent 4,337,710) — United States Patent and Trademark Office
- Litco's New 48x45 Automotive Presswood Pallet — Pallet Enterprise
- ISPM 15 Regulation of wood packaging material in international trade — IPPC / FAO