All wooden pallets used on container ships must be heat treated to meet international standards.
A pallet machine is essentially an independent assembly line used to make pallets. Pallets are platforms on which material is stacked and are built to facilitate relocation, usually with a forklift. As pallets vary in size and structural material, the machinery for pallet production varies.
In the manufacture of wooden pallets, the function of the palletizer is to allow efficient positioning of stringers or blocks to which the deck boards are nailed. When the stringers and deck boards are placed on a movable front platform, nailing the deck to the stringers is done. A grouped nail gun, usually three pneumatic nail heads positioned over the stringers, is manually moved across the deck and the nails are driven into the deck boards, securing them to the stringers.
In a small shop, the pallet is manually overturned and the lower deck boards are similarly fixed. With a more sophisticated palletizer, this is done robotically. Pallets are moved on a conveyor belt to be stacked by a forklift and await transport to the end user. Pallet assembly using a small pallet usually produces a full pallet per minute, while more complex machines have a higher rate of pallet assembly.
For plastic pallets, an injection molding process is typically used. A pallet mold is made of steel or aluminum and the molten plastic is forced into the mold, creating the desired pallet. While this method of pallet manufacturing is more expensive to set up, the resulting pallets are very durable and typically have a longer shelf life.
Pallets made from wood, new or recycled, are the most commonly used and are available in a variety of sizes and configurations. While the pallet design with stringers is the most common, wooden pallets used as skids or with a block design are also an important part of pallet production. With a modestly priced pallet machine, these stringer or “warehouse” pallets, with a standard size of 48 inches (about 122 cm) by 40 inches (about 106 cm), can be manufactured in a small shop with just A person.
A pallet company large enough to supply pallets to large industrial companies often makes custom pallet manufacturing available to its customers. Custom pallet production can include sizes, materials or configurations to meet the specific needs of a large customer. A pallet machine, using wood or plastic, can be dedicated to a unique product in a large pallet manufacturing company where a small pallet assembly plant could not afford it.
The manufacture of pallets for international shipments has additional requirements. The International Phytosanitary Measure known as ISPM 15 requires pallet manufacturers to ensure that no harmful pests travel with the pallet. Plastic pallets are automatically ISPM 15 compliant, but wooden pallets must be heat treated or fumigated, requiring additional steps in the production of these pallets.