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forklift history

Forklift truck
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"Pallet truck" redirects here. For the smaller pallet-moving tool sometimes called a pallet truck, see pallet jack.

A US airman operating a Hyster forklift Grandall Material Handler 544 telescoping forklift used in constructionA forklift (also called a lift truck, a high/low, a stacker-truck, trailer loader, sideloader, fork truck, tow-motor or a fork hoist) is a powered industrial truck used to lift and transport materials. The modern forklift was developed in the 1920s by various companies including the transmission manufacturing company Clark and the hoist company Yale & Towne Manufacturing.[1] The forklift has since become an indispensable piece of equipment in manufacturing and warehousing operations.

Contents [hide]
1 History
2 Design types
2.1 Specialty trucks
2.2 Automated forklift trucks
3 Counterbalanced forklift components
3.1 Attachments
4 Forklift control and capabilities
4.1 General operations
4.2 Forklift use in warehouse and distribution centers
5 Lift truck associations and organizations
6 Forklift safety organizations
6.1 Standards
6.2 Forklift Training in the United Kingdom
7 Manufacturer's worldwide ranking
8 See also
9 References
10 External links
10.1 Safety Information
10.2 Forklift truck history

[edit] History

Toyota's first lift truckThe middle nineteenth century through the early twentieth century saw the developments that led to today's modern forklifts. The Pennsylvania Railroad in 1906 introduced battery powered platform trucks for moving luggage at their Altoona, Pennsylvania train station. World War I saw the development of different types of material handling equipment in the United Kingdom by Ransomes, Sims and Jeffries of Ipswich. This was in part due to the labor shortages caused by the war. In 1917 Clark in the United States began developing and using powered tractor and powered lift tractors in their factories. In 1919 the Towmotor Company and Yale & Towne Manufacturing in 1920 entered the lift truck market in the United States.[2]

Continuing development and expanded use of the forklift continued through the 1920s and 1930s. World War II, like World War I before, spurred the use of forklift trucks in the war effort. Following the war, more efficient methods for storing products in warehouses were being implemented. Warehouses needed more maneuverable forklift trucks that could reach greater heights. New forklift models were made that filled this need.[3] In 1956 Toyota introduced its first lift truck model, the Model LA, in Japan and sold its first forklift in the United States in 1967. [4]

[edit] Design types


A truck mounted forklift called "Moffet".
A Raymond reach truck. Note the pantograph allowing the extension of the forks in tight aisles. This electric machine weighs over 7000lbs and can lift 4000lbs to 24 feet in the air.The following is a list of the more common lift truck types. It is arranged from the smallest type of lift to largest:

Hand pallet truck
Walkie low lift truck (powered pallet truck, usually electrically powered)
Rider low lift truck
Towing tractor
Walkie stacker
Rider stacker
Reach truck (small forklift, designed for small aisles, usually electrically powered, so-named because the forks can extend to reach the load)
Electric counterbalanced truck
IC counterbalanced truck
Sideloader
Telescopic handler
Walkie Order Picking truck
Rider Order Picking truck (commonly called an "Order Picker"; like a small forklift, except the operator rides up to the load and transfers it article by article)
Articulated Very Narrow Aisle Counterbalanced trucks (commonly called "Flexi or Bendi Truck")
Guided Very Narrow Aisle truck - 'Man Down' (a type of reach truck designed for aisles less than five feet wide) and 'Man Riser' Combination pickcle Picker/ Stacker truck
Truck Mounted Forklift / Sod Loader
[edit] Specialty trucks
At the other end of the spectrum from the counterbalanced forklift trucks are more 'high end' specialty trucks:

Articulated Counterbalance Trucks
These are, unlike most lift trucks, front wheel steer, and are a hybrid VNA (Very Narrow Aisle) truck designed to be both able to offload trailers and place the load in narrow aisle racking. Increasingly these trucks are able to compete in terms of pallet storage density, lift heights and pallet throughput with Guided Very Narrow Aisle trucks.

Guided Very Narrow Aisle Trucks
These are rail or wire guided and available with lift heights up to 40' non top-tied and 98' top-tied. Two forms are available; 'man-down' and 'man-riser' where the operator elevates with the load for increased visibility or for multilevel 'break bulk' order picking. This type of truck, unlike Articulated Narrow Aisle Trucks, requires a high standard of floor flatness.

Explosion proof trucks
These are for operation in potentially explosive atmospheres found in chemical, petrochemical, pharmaceutical, food and drink, logistics or other industries handling flammable material. Commonly referred to as Pyroban trucks, in Europe they must meet the requirements of the ATEX 94/9/EC Directive if used in Zone 1, 2, 21 or 22 areas and be maintained accordingly.

In North America, internal combustion powered industrial vehicles carry Underwriters Laboratories ratings that are part of UL 558. Industrial trucks that are considered "explosion proof" carry the designations GS for gasoline powered, DS for diesel powered, LPS for liquified propane or GS/LPS for a dual fuel gasoline/liquified propane powered truck.[5]

U.S. Military 10K-AT "Adverse Terrain"
[edit] Automated forklift trucks
In order to decrease work wages, reduce operational cost and improve productivity, automated forklifts have also been developed.[6][7] Automated forklifts are also called forked automated guided vehicles and are already available from a growing number of suppliers.[8]

[edit] Counterbalanced forklift components
A typical counterbalanced forklift contains the following components:[9]


Image of an electric forklift with component descriptionsTruck Frame - is the base of the machine to which the mast, axles, wheels, counterweight, overhead guard and power source are attached. The frame may have fuel and hydraulic fluid tanks constructed as part of the frame assembly.
Counterweight - is a heavy cast iron mass attached to the rear of the forklift truck frame. The purpose of the counterweight is to counterbalance the load being lifted. In an electric forklift the large lead-acid battery itself may serve as part of the counterweight.
Cab - is the area that contains a seat for the operator along with the control pedals, steering wheel, levers, switches and a dashboard containing operator readouts. The cab area may be open air or enclosed, but it is covered by the cage-like overhead guard assembly. The 'Cab' can also be equipped with a Cab Heater for cold climate countries.
Overhead Guard - is a metal roof supported by posts at each corner of the cab that helps protect the operator from any falling objects. On some forklifts, the overhead guard is an integrated part of the frame assembly.
Power Source - may consist of an internal combustion engine that can be powered by LP gas, CNG gas, gasoline or diesel fuel. Electric forklifts are powered by either a battery or fuel cells that provides power to the electric motors. The electric motors used on a forklift may be either DC or AC types.
Tilt Cylinders - are hydraulic cylinders that are mounted to the truck frame and the mast. The tilt cylinders pivot the mast to assist in engaging a load.
Mast - is the vertical assembly that does the work of raising and lowering the load. It is made up of interlocking rails that also provide lateral stability. The interlocking rails may either have rollers or bushings as guides. The mast is driven hydraulically, and operated by one or more hydraulic cylinders directly or using chains from the cylinder/s. It may be mounted to the front axle or the frame of the forklift.
Carriage - is the component to which the forks or other attachments mount. It is mounted into and moves up and down the mast rails by means of chains or by being directly attached to the hydraulic cylinder. Like the mast, the carriage may have either rollers or bushings to guide it in the interlocking mast rails.
Load Back Rest - is a rack-like extension that is either bolted or welded to the carriage in order to prevent the load from shifting backward when the carriage is lifted to full height.
Attachments - may consist of forks or tines that are the L-shaped members that engage the load. A variety of other types of material handling attachments are available. Some attachments include sideshifters, slipsheet attachments, carton clamps, multipurpose clamps, rotators, fork positioners, carpet poles, pole handlers, container handlers and roll clamps.
[edit] Attachments
Below is a list of common forklift attachments:[10]

Dimensioning Devices-fork truck mounted dimensioning systems provide dimensions for the cargo to facilitate truck trailer space utilization and to support warehouse automation systems. The systems normally communicate the dimensions via 802.11 radios. NTEP certified dimensioning devices are available to support commercial activities that bill based on volume.
Sideshifter - is a hydraulic attachment that allows the operator to move the tines (forks) and backrest laterally. This allows easier placement of a load without having to reposition the truck.[11]
Rotator - To aid the handling of skids that may have become excessively tilted and other specialty material handling needs some forklifts are fitted with an attachment that allows the tines to be rotated. This type of attachment may also be used for dumping containers for quick unloading.
Fork Positioner - is a hydraulic attachment that moves the tines (forks) together or apart. This removes the need for the operator to manually adjust the tines for different sized loads.
Roll and Barrel Clamp Attachment - A mechanical or hydraulic attachment used to squeeze the item to be moved. It is used for handling barrels, kegs, or paper rolls. This type of attachment may also have a rotate function. The rotate function would help an operator to insert a vertically stored paper into the horizontal intake of a printing press for example.
Pole Attachments - In some locations, such as carpet warehouses, a long metal pole is used instead of forks to lift carpet rolls. Similar devices, though much larger, are used to pick up metal coils.
Carton and Multipurpose Clamp Attachments - are hydraulic attachments that allow the operator to open and close around a load, squeezing it to pick it up. Products like cartons, boxes and bales can be moved with this type attachment. With these attachments in use, the forklift truck is sometimes referred to as a clamp truck.
Slip Sheet Attachment (Push - Pull) - is a hydraulic attachment that reaches forward, clamps onto a slip sheet and draws the slip sheet onto wide and thin metal forks for transport. The attachment will push the slip sheet and load off the forks for placement.
Drum Handler Attachment - is a mechanical attachment that slides onto the tines (forks). It usually has a spring loaded jaw that grips the top lip edge of a drum for transport. Another type grabs around the drum in a manner similar to the roll or barrel attachments.
Man Basket - a lift platform that slides onto the tines (forks) and is meant for hoisting workers. The man basket has railings to keep the person from falling and brackets for attaching a safety harness. Also, a stap or chain is used to attach the man basket to the carriage of the forklift.
Telescopic Forks - are hydraulic attachments that allow the operator to operate in warehouse design for "double-deep stacking", which means that two pallet shelves are placed behind each other without any aisle between them.
Scales -Fork truck mounted scales enable operators to efficiently weigh the pallets they handle without interrupting their workflow by travelling to a platform scale. Scales are available that provide legal-for-trade weights for operations that involve billing by weight. They are easily retrofitted to the truck by hanging on the carriage in the same manner as forks hang on the truck.
Any attachment on a forklift will reduce its nominal load rating, which is computed with a stock fork carriage and forks. The actual load rating may be significantly lower.

[edit] Forklift control and capabilities
Forklift trucks are available in many variations and load capacities. In a typical warehouse setting most forklifts used have load capacities between one to five tons. Larger machines, up to 50 tons lift capacity are used for lifting heavier loads, including loaded shipping containers.[12]


a typical load capacity chart‎

In addition to a control to raise and lower the forks (also known as blades or tines), the operator can tilt the mast to compensate for a load's tendency to angle the blades toward the ground and risk slipping off the forks. Tilt also provides a limited ability to operate on non-level ground. Skilled forklift operators annually compete in obstacle and timed challenges at regional forklift rodeos.

[edit] General operations

A forklift transporting a pallet of potted plants.Forklifts are rated for loads at a specified maximum weight and a specified forward centre of gravity. This information is located on a nameplate provided by the manufacturer, and loads must not exceed these specifications. In many jurisdictions it is illegal to remove or tamper with the nameplate without the permission of the forklift manufacturer.

An important aspect of forklift operation is that most have rear-wheel steering. While this increases maneuverability in tight cornering situations, it differs from a driver’s traditional experience with other wheeled vehicles. While steering, as there is no caster action, it is unnecessary to apply steering force to maintain a constant rate of turn.

Another critical characteristic of the forklift is its instability. The forklift and load must be considered a unit with a continually varying centre of gravity with every movement of the load. A forklift must never negotiate a turn at speed with a raised load, where centrifugal and gravitational forces may combine to cause a disastrous tip-over accident. The forklift are designed with a load limit for the forks which is decreased with fork elevation and undercutting of the load (i.e. load does not butt against the fork "L"). A loading plate for loading reference is usually located on the forklift. A forklift should not be used as a personnel lift without the fitting of specific safety equipment, such as a "cherry picker" or "cage".

[edit] Forklift use in warehouse and distribution centers
Forklifts are a critical element of warehouses and distribution centers. It’s imperative that these structures be designed to accommodate their efficient and safe movement.

In the case of Drive-In/Drive-Thru Racking, a forklift needs to travel inside a storage bay that is multiple pallet positions deep to place or retrieve a pallet. Oftentimes, forklift drivers are guided into the bay through guide rails on the floor and the pallet is placed on cantilevered arms or rails. These maneuvers require well-trained operators. Since every pallet requires the truck to enter the storage structure, damage is more common than with other types of storage. In designing a drive-in system, dimensions of the fork truck, including overall width and mast width, must be carefully considered.[13]

[edit] Lift truck associations and organizations
There are many national as well as continental associations related to the industrial truck industry. Some of the major organizations are listed as:

Industrial Truck Association (ITA) (North America)[14]
Material Handling Equipment Distributors Association (MHEDA) (North America)[15]
Fédération Européenne de la Manutention - European Federation of Materials Handling (FEM)[16]
Fork Lift Truck Association (FLTA) (UK)[17]
British Industrial Truck Association (BITA)[18]
Japan Industrial Vehicles Association (JIVA)[19]
Korean Construction Equipment Manufacturers Association (KOCEMA)[20]
There are many significant contacts among these organizations and they have established joint statistical and engineering programs. One program is the World Industrial Trucks Statistics (WITS) which is published every month to the association memberships. The statistics are separated by area (continent), country and class of machine. While the statistics are generic, and do not count production from most of the smaller manufacturers, the information is significant for its depth. These contacts have brought to a common definition of a Class System which all the major manufacturers adhere to.

[edit] Forklift safety organizations
[edit] Standards
Forklift safety is subject to a variety of standards world wide. The most important standard is the ANSI B56—of which stewardship has now been passed from the American National Standards Institute (ANSI) to the Industrial Truck Standards Development Foundation after multi-year negotiations. ITSDF is a non-profit organization whose only purpose is the promulgation and modernization of the B56 standard.[21]

Other standards have been implemented in the United States by the Occupational Safety and Health Administration (OSHA) and in the United Kingdom by the Health and Safety Executive.[22] In many countries forklift truck operators must be trained and certified to operate forklift trucks. Certification may be required for each individual class of lift that an operator would use.

[edit] Forklift Training in the United Kingdom
In the UK, the Provision and Use of Work Equipment Regulations (PUWER) state that operators of fork lift trucks must be adequately trained in their operation, but the nature of this training is not specified. Third party organisations have developed de-facto 'best practice' standards for forklift training, commonly referred to in the UK as a 'forklift license', but such training is not a legal requirement as is commonly believed.[23] Organised training however helps to demonstrate that an employer has taken steps to ensure its 'duty of care' in the unfortunate event of an accident. The details below represent the de-facto standards proscribed by training organisations.

In the UK, Forklift Training is carried out by a number of different organisations, which all Forklift Instructors must be registered with at least one of them. Although R.T.I.T.B. operators are registered on a database which has to be renewed a 3 yearly basis, the amount of time determined between refresher courses is subject to the H&S Executive, Insurance companies or company policies. The H&S Executive (HSG136 Workplace Transport Safety) does recommend re-training/testing every 3 to 5 years[citation needed].

United Kingdom Forklift Instructors can be registered to one of the following, though registration is not compulsory to instruct;
RTITB
Independent Training Standards Scheme and Register (ITSSAR)
Association of Industrial Truck Trainers (AITT)
National Plant Operators Registration Scheme (NPORS)
CITB-ConstructionSkills
Lantra - Sector Skills Council for the environmental and land-based sector

There are various different training companies across the UK that can provide training on-site and off-site, these can be independent instructors or part of a training company. There are also various training centre's across the United Kingdom that can provide individuals not already trained to use a Forklift Truck to help gain a certificate of competence.

In the United Kingdom training falls into four different categories;
REFRESHER - People who have gained a Forklift Training Certificate and need to be brought up to date with new laws and/or regulations.
CONVERSION - People who have been trained on a type of truck recently, and need to start using a different type.
SEMI-EXPERIENCED - People who are competent on a forklift truck, but have never been certificated.
NOVICE - Never been on a Forklift Truck before and never been certificated.
The courses can last for 1 day for a Refresher or a Conversion course, to 5 days for a Novice course. It is recommended that United Kingdom Forklift Instructors train a maximum of Three People per day, this does not include classroom work.

[edit] Manufacturer's worldwide ranki
WWW.PCNFORKLIFT.COM

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