Wood pallets have traditionally been the way in which material is moved from vendor to customer and then onto the consumer. The wood pallet sits in warehouses and stores throughout the world. In the US there are millions of pallets in use every day and the vast majority is made from wood. For the manufacturer of the wood pallet there are voluntary guidelines that have been developed by the National Wooden Pallet and Container Association (NWPCA) to ensure that every pallet that is used in the shipping and storing of materials is as safe as possible.
Standard for Wood Pallets
The National Wooden Pallet and Container Association has developed a uniform standard for the wood pallet that explicitly describes how a wood pallet should be manufactured, the necessary performance of the pallet, and the how a wood pallet should be sanitized. This standard was approved by the NWPCA in May of 2012 and gives anyone who is involved with wood pallets the information that they need to deal with any situation involving pallets.
Manufacture of Pallets
The NWPCA guidelines aim to give a minimum quality requirement for wood pallets. The section of the guidelines referring to the manufacture of pallets includes descriptions on components, definitions and description of fasteners, dimensional tolerances, moisture content levels, and information on the repair and remanufacture of pallets. There are two classes of pallets; stringer pallet, which uses a frame of three or more parallel pieces of timber, and the block pallet, which uses both parallel and upright stringers for more efficient handling.
The Pallet can be made of a number of different components; lumber, plywood or OSB (oriented strand board), wood based composites, and engineered wood components. The components should be used with fasteners such as driven nails and staples, steel carriage bolts, wood screws, and lag screws. There should be a minimum number of fasteners for each connection, based on the width of the component involved, and the placement of those fasteners is covered in the specification.
The repair of pallets is important as it reduces the amount of pallets being sent to landfills and it is a benefits to companies that use pallets as it reduces the cost of purchasing or manufacturing pallets. The specification gives detailed information as to how to repair the pallet given any number of scenarios, such as missing wood, splits, de-lamination, or twisted blocks.
Performance of Pallets
Each pallet should be able to do the job it was designed to do, and as such the NWPCA specification gives companies information on the performance of a pallet, given a number of conditions. The testing of pallets is defined by an ISO test method; ISO 8611-1:2011 specifies the test methods available for evaluating new flat pallets for materials handling. The test methods are split into groups for nominal load testing, maximum working load testing and durability comparison testing. There are two distinct types of load test: proof testing and testing to destruction. The most common pallet testing is testing to destruction, as it is only possible to measure a pallet load safety factor if the item under test has exceeded safe working load up to breaking load.
Sanitation of Wood Pallets
The NWPCA specification describes the phytosanitation of wood pallets. The NWPCA indicates that all pallets should conform to the International Standards for Phytosanitary Measures Publication No. 15 (ISPM 15). This standard has been adopted by the US and a growing number of countries. The ISPM 15 was developed to reduce the risk of introduction and spread of quarantine pests associated with the movement in international trade of wood packaging material made from raw wood. The treatments of wood include heat treatment, which specifies the heating to 56 C for a minimum duration of 30 continuous minutes. Other treatments include the use of methyl bromide, which is used to fumigate the wood over a period of 24 hours.
What is a pallet?
Pallets, a flat transport structure that holds and supports goods in a sturdy fashion while being lifted by a forklift or other jacking device, are a big part of international shipping. When you are ready to ship globally, you must decide: Do you need to palletize your freight? What kind of pallet should be used—new or used, wood or plastic?
Is a horizontal platform device used as a base for assembling, storing, handling and transporting materials and products as a unit load, typically equipped with a superstructure. Additionally, a pallet provides protection to the product on it, and the coverage of the bottom deck of the pallet can prevent damage to palletized goods upon which another pallet may be stacked. More currently, a pallet affixed with RFID or GPS technology can also offer benefits of information and or location tracking both for the pallet itself, as well as for the merchandise it is carrying.
The pallet is the most common base for the unit load, which includes pallet and goods stacked atop it, typically secured by stretch wrap, strapping, shrink wrap, adhesive, pallet collar, or other means of unit load stabilization.
The history of pallets has shown their gradual development over the last century, helping enable the development of modern logistics. The importance of pallets to supply chain applications today has been significant, allowing dramatic efficiencies in the handling and transport of unit loads. Additional refinements were added to pallet design and management during World War 2. For example, pallet reuse in the supply chain became increasingly practiced. The pallet pooling concept began to be seriously discussed during this time and has evolved into a key strategy for pallet suppliers.
What Materials Are Pallets Made From?
Pallets are made from various types of materials. The wood pallet dominates the marketplace, followed by plastic pallets, paper pallets, wood composite pallets and metal pallets, which also have a presence. Please note that attributes of various pallet materials can have implications for material handler safety.
Wood pallets offer a great combination of weight, stiffness, durability and cost, not to mention a widespread pallet recycling infrastructure. Custom pallets sizes can be easily fabricated from timber components. Plastic pallets typically are more expensive than wood pallets for comparable applications, but are valued for such attributes as extreme durability, precision of manufacture, and ease of sanitation. Other important buying considerations include pallet weight, and considerations for export pallets, such as ISPM-15 compliance or exemption for international shipping.
What are the main pallet designs?
NWPCA’s ( National Wooden Pallet and container Association ) Uniform Standard for Wood Pallets begins by classifying pallets as either stringer or block. It then goes on to differentiate the common entry types for wood pallet, which refers to how many directions they may be entered by pallet trucks and forklifts. These include two-way entry pallets, which can be entered at either end, four-way pallets, which can be entered from all four sides, and partial four-way entry pallets, which can be entered by forklifts and pallet trucks at each end, but only by forklifts through notched stringers on the sides.
Pallet style refers to whether a pallet has a single or double face (single or both top and bottom deck), and whether a pallet is reversible (either side can be used for the top deck) or non-reversible (having top and bottom deck but only one intended for use as a top deck). The standard then goes on to discuss top and bottom deck options. A single faced pallet is also commonly as a skid.
What are the main pallet sizes?
Although pallets may be fabricated to various custom sizes, there are some typical sizes that are most commonly used. It should be pointed out that in describing the size of pallets, one starts with the stringer or stringer board length, first, followed by the pallet width, typically the length of the deck boards.The main pallet size or pallet dimension in North America is 48×40 inches. There are six pallet sizes recognized by ISO. Here is a list, including the region most commonly used: