Pallet
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- A Pallet can also be a small, hard, or temporary bed (a term heavily used in the southern United States to describe a makeshift bed consisting of a blanket and a pillow on the floor).
A pallet is a flat transport structure designed to support a variety of goods in a stable fashion while being lifted by any mobile forklift or other jacking device. The goods are placed on top of the pallet, and can be secured to it by straps or stretch-wrapped plastic film. While the majority of pallets are made of wood, pallets manufactured from plastic, metal, paper can also be found. A pallet is sometimes colloquially called a skid, by back-formation from skid loader. A wooden pallet costs anything from a few pounds per unit to ten times that number, depending on quantities and type ordered. In North America a standard black plastic pallet costs (wholesale) from $20 - $70 US Dollars. They are available in bulk to businesses but usually not to individuals. While a wooden pallet is close to a plastic one in value, it is in general cheaper to buy. But the life expectancy of a wooden pallet is relatively short as plastic pallets can last much longer in normal use. Plastic pallets are stronger, more hygienic and safer in some applications. Using plastic pallets can be environment-friendly if they are disposed of properly after their longer life.
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[edit] Overview
The gradual advent of containers for the transport of nearly all goods has spurred the use of pallets because the containers always offer the clean, level surfaces needed to make pallet movement economical. Most pallets can easily carry a load of 1,000 kg (about 2,000 lb). Today, over half a billion pallets are manufactured each year and about two billion pallets are in use across the United States alone.
One of the greatest advantages of pallets is the number of ways they can be moved around. They can be hauled by forklift trucks of different sizes and they can also be transported by hand-pumped and hand-drawn jacks which require no more than muscle power, wherever a solid and even floor with enough room is available. A forklift truck often costs the same as a luxury automobile but a good reconditioned hand-drawn "pumper" jack can be obtained for a few hundred euros. The greatest investment is thus in the time it takes to plan for clearances and level surfaces in the construction of commercial or industrial buildings where the use of pallets could be economical.
[edit] History
[edit] Development of Commercial Transport Packaging
Skids and pallets were slowly introduced throughout the early 20th century; wooden boxes, crates, barrels and kegs were much more commonly used to unitize, protect, store and transport goods. The predecessor of the wooden pallet was the wooden skid, which consisted of stringers fastened to a top deck. It first appeared in American factories in conjunction with the low lift truck. A crude low lift hand truck was invented in 1887 and a more durable, all-steel low lift truck design was introduced in 1909.
The high lift fork truck first appeared in 1915. With further modification in 1919, the truck could lift loads several feet high while other improvements included cantilever design and forks. The emergence of forks as well during the same period enabled lift trucks to handle a much greater range of materials.
Another development was the new capability of the mast of the fork lift to tilt both forward and back, independent of the lifting mechanism. These developments, along with the emergence of the double-faced pallet during the same time period, allowed for tiering of unit loads. As early as 1926, the essence of the modern lift truck had been developed. Now, pallets no longer were simply a means of moving materials within the plant. High lift trucks made possible vertical stacking of unit loads and a resulting dramatic improvement of warehouse and plant storage efficiencies.
[edit] Evolution of the Pallet
The pallet evolved in stages. Spacers were used between loads to allow fork entry, progressing to the placement of boards atop stringers to make skids. Eventually boards were fastened to the bottom to create the pallet. The addition of bottom boards on the skid, which appeared by 1925, resulted in the pallet. With the bottom deck, several problems common to the single faced skid were addressed. For example, the bottom boards provided better weight distribution and reduced product damage; they also provided better stacking strength and rigidity. Lift truck manufacturers promoted the idea of using more vertical area of a plant for stock storage.
[edit] Impact of Pallet on Rail Transport
Pallets and forklifts also provided much quicker turnaround of rail cars and ships. In 1931, three days were required to unload a boxcar containing 13,000 cases of unpalletized canned goods. When the same amount of goods were loaded into the railway trucks on pallets or skids, the identical task took only four hours. With the entry of the U.S. into World War II, the urgency for material handling reform changed almost overnight. Palletization was regarded as an enormous opportunity to help the U.S. armed forces do more with less. Palletized loads could handle more goods with fewer people, freeing up men for military duty; it also could increase warehouse storage capacity and throughput, reducing the need for additional warehouse capacity. Pallets were used somewhat in the European theater, but they were put to work extensively in the Pacific.
[edit] Standardization and Regulation
[edit] Dimensions
No universally accepted standards for pallet dimensions exist. Companies and organizations utilize hundreds of different pallet sizes around the globe.[1] While no single dimensional standard governs pallet production, a number of different sizes have gained significant widespread usage.
[edit] ISO Pallets
International Organization for Standardization (ISO) sanctions six pallet dimensions, detailed in ISO Standard 6780: Flat pallets for intercontinental materials handling -- Principal dimensions and tolerances:[2]
Dimensions (mm) | Dimensions (inches) | Region |
---|---|---|
1200 x 1000 | 47.24 x 39.37 | Europe, Asia |
1200 x 800 | 47.24 x 31.50 | Europe |
1219 x 1016 | 48.00 x 40.00 | North America |
1140 x 1140 | 44.88 x 44.88 | Australia |
1100 x 1100 | 43.30 x 43.30 | Asia |
1067 x 1067 | 42.00 x 42.00 | North America, Europe, Asia |
[edit] North American Pallets
There are ten pallet sizes that are commonly used in North America. Of the top ten, the most commonly used by far is the Grocery Manufacturers' Association (GMA) pallet, which accounts for 30% of all new wood pallets produced in the United States.[3] The ISO also recognizes the GMA pallet footprint as one of its six standard sizes.
Dimensions (in.) | Production Rank | Industries Using |
---|---|---|
48 x 40 | 1 | Grocery, many others |
42 x 42 | 2 | Telecommunications, Paint |
48 x 48 | 3 | Drums |
40 x 48 | 4 | Department of Defense, Cement |
48 x 42 | 5 | Chemical, Beverage |
40 x 40 | 6 | Dairy |
48 x 45 | 7 | Automotive |
44 x 44 | 8 | Drums, Chemical |
36 x 36 | 9 | Beverage |
48 x 36 | 10 | Beverage, Shingles, Packaged Paper |
[edit] European Pallets
In Europe, the EuroPallet(an EUR standard pallet) is commonly used and measures 80 by 120 by 12 cm.[4] It is also called a CEN pallet and it is used mainly for retail business. Manufacturers of EuroPallets must be sanctioned by the EuroPallet Pallet Association (EPAL), which also governs which types of nails and lumber may be used in construction. The four common sizes of EuroPallets are:[5]
Name | Dimensions (mm) |
---|---|
Pallet EUR | 800 x 1200 |
Pallet EUR 2 | 1200 x 1000 |
Pallet EUR 3 | 1000 x 1200 |
Pallet EUR 6 | 800 x 600 |
[edit] Standard-setting Organizations
A number of different organizations and associations around the world work towards establishing and promulgating standards for pallets. Some strive to develop universal standards for pallet dimensions, types of material used in construction, performance standards, and testing procedures. Other organizations choose to focus on pallet standards for a specific industry (such as the groceries) or type of material (such as wood).
[edit] ISO Technical Committee 51: Pallets for unit load method of materials handling
ISO TC 51 states its scope of work entailing the "standardization of pallets in general use in the form of platforms or trays on which goods may be packed to form unit loads for handling by mechanical devices".[6] The Technical Committee works in conjunction with other Technical Committees focused on transportation infrastructure to develop interrelated standards. TC 51 is responsible for developing ISO Standard 6780: Flat pallets for intercontinental materials handling -- Principal dimensions and tolerances as well as sixteen other standards related to pallet construction and testing.
[edit] National Wood Pallet and Container Association
The National Wood Pallet and Container Association (NWPCA) is a trade organization based in the United States devoted to representing the interests of wood pallet and container manufacturers. The NWPCA defines its mission as helping its membership create cost-effective, environmentally-friendly solutions to customers' needs.[7]. Towards that end, the NWPCA developed a bevy of resources to assist its membership, including the Pallet Design System (PDS), which allows users to develop and analyze pallet designs.[8]
[edit] European Committee for Standardization (Comité Européen de Normalisation)
In addition to the other standards it publishes, the European Committee for Standardization, also known as the Comité Européen de Normalisation (CEN), produces standards for pallets. While the standards are voluntary in nature, many companies and organizations involved in transportation have adopted them. The major standard for pallets produced by CEN is ICS: 55.180.20 General purpose pallets[9]
[edit] Timcon - Timber Packaging and Pallet Confederation
Timcon (Timber Packaging and Pallet Confederation) is based in the UK and is a National Trade Association that represents the timber packaging industry interests, especially the manufacturers of timber pallets, packing cases crates and export packaging. [1]
Further information About TIMCON links and other standards can be found here [2]
[edit] Phytosanitary Compliance
Due to the International Plant Protection Convention (abbreviated IPPC), most pallets shipped across national borders must be made of materials that are incapable of being a carrier of invasive species of insects and plant diseases. The standards for these pallets is specified in ISPM 15.
Pallets made of raw untreated wood, are not compliant with ISPM 15. To be compliant the pallets must be treated by either of the following means under the supervision of an approved agency.
- Heat treatment The wood must be heated to achieve a minimum core temperature of 56ºC for at least 30 minutes. Pallets treated via this method bear the initials HT by the IPPC logo.
- Chemical fumigation The wood must be fumigated with methyl bromide. Pallets treated via this method bear the initials MB by the IPPC logo.
Pallets made of non wood materials such as steel, aluminum, plastic, or made of engineered wood products, such as plywood, oriented strand board, or cardboard do not need IPPC approval.
[edit] Pallet Construction
[edit] Types of Pallets
Although pallets come in all manner of sizes and configurations, all pallets fall into two very broad categories: "stringer" pallets and "block" pallets. The National Wooden Pallet & Container Association has developed a Pallet Design System PDS© to manufacture pallets. PDS© is a computer program that allows the pallet maker to generate the best suited pallet design for a specific load and generate several options for wood selections to further reduce costs. Cap3d is an other program that does the same thing.
[edit] Stringer Pallet
Stringer pallets use a frame of three parallel pieces of timber (called stringers). The top deckboards are then affixed to the stringers to create the pallet structure. Stringer pallets are also known as "two-way" pallets, since a pallet-jack may only lift it from two directions instead of four.
[edit] Block Pallet
Block pallets (also referred to as GKN pallets) are typically stronger than stringer pallets. Block pallets utilize both parallel and perpendicular stringers to better facilitate efficient handling. A block pallet is also known as a "four-way" pallet, since a pallet-jack may be used from any side to move it.
[edit] Materials Used
The cheapest pallets are made of softwood and are often considered as expendable, to be discarded as trash, along with other wrapping elements, upon reaching destination. These pallets are of a very simple construction which permits lifting from one of two opposite positions only. Slightly more complex hardwood pallets and most plastic pallets and metal pallets can be lifted from all four sides. These costlier pallets usually require a deposit and are returned to the sender or resold as used. Many of these "four way" pallets are color coded according to the loads they can bear, and other attributes.
Wooden pallet construction specifications can depend on the pallet's intended use: general, FDA, storage, chemical, export; the expected load weight; type of wood desired: recycled, hard, soft, kiln Dried or combo (new & recycle); and even the type of fasteners desired to hold the pallet together: staples or nails.
Paper pallets are often used for light loads, but engineered paper pallets are increasingly used for loads that compare with wood. Paper pallets are also used where recycling and easy disposal is important.
Plastic pallets are usually made of a plastic resin which is more durable and lighter weight than most plastics. Plastic pallets can not easily be repaired when broken which is why they are mostly used by logistics service providers who can easily replenish stock for its customers. Plastic pallets offer several benefits over traditional materials like wood, such as they are resistant to oder and can easily be sanitized for international shipping. Plastic pallets also work better with toxic materials for purposes of sanitation and plastics are impervious to most acids.
Businesses in retail or manufacturing with accommodations for loading and unloading standard sized pallets and internal procedures for taking advantages of the modular nature of the pallets usually have a distinct advantage over businesses which do not exploit standardized pallets. The exceptions are those establishments which sell small quantities of luxury items such as jewelry stores or extra large items such as cars. But even they are at least indirectly affected. For instance, the distributors of costume jewelry and like items would normally use pallets in their warehouses and car manufacturers have long ago integrated pallets in their logistics systems for transporting components from their suppliers and for moving around spare parts.
[edit] References
- ^ Raballand, Gaël and Aldaz-Carroll, Enrique, "How Do Differing Standards Increase Trade Costs? The Case of Pallets" (February 2005). World Bank Policy Research Working Paper No. 3519.
- ^ ISO 6780:2003 - Flat pallets for intercontinental materials handling -- Principal dimensions and tolerances
- ^ Clarke, John, "Pallets 101: Industry Overview and Wood, Plastic, Paper, and Metal Options"
- ^ "EuroPallets: Good or Bad for Business"
- ^ EuroPallet Pallet Association (EPAL) Paletten-System
- ^ ISO Technical Committee 51: Pallets for unit load method of materials handling
- ^ National Wood Pallet and Container Association Mission
- ^ Pallet Design System (PDS)
- ^ ICS: 55.180.20 General purpose pallets
[edit] External links
- History of the Pallet
- Pallet Construction Overview
- Breaking News from 1945: Pallet Standardization Enhances Efficiency
- Reference site about EUR EPAL pallet
[edit] See also
- ULD, lightweight aluminium and plastic pallet or container for aircraft.
- IPPC, Adoption of these guidelines impact the treatment of pallets used for international shipments.
- 463L master pallet, a wood and aluminium air cargo pallet primarily used by the US Air Force
- Concrete block
- Crane (machine)