Chariot élévateur ( English )
Un chariot élévateur est un engin de manutention destiné au transfert de charges dans les usines ou les halles de stockage. Ses domaines d'activité sont principalement la reprise des produits finis des chaînes de fabrication vers les lieux de stockage, le chargement ou déchargement des moyens de transport tel les wagons ou camions , l'aide au chargement ou déchargement dans les cales des navires, mais sa grande souplesse lui permet beaucoup d'usages.
Manutention d'un conteneur de 40"
Les premières versions ont été des chariots à fourches fabriqués en 1917 par l'industriel anglais installé aux États-Unis, Eugene Clark . La renommée de Clark dans le domaine a fait de ce nom de marque un nom commun , c'est toutefois aussi vrai de Fenwick qui fut le premier à construire de telles machines en France.
Le chariot élévateur est connu pour sa compacité et son aptitude à la manutention de palettes . Il existe toute une variété de modèles pouvant transporter des charges de 1,5 tonnes (palettes) à plus de 40 tonnes ( conteneurs ), et pouvant gerber sur des hauteurs considérables (plus de 10 mètres). Il est équipé naturellement de deux fourches, mais il peut être aussi équipé de pinces hydrauliques pour la prise de bobines ou de rouleaux de papier, de palonniers à conteneurs, de pieux horizontaux pour les pièces cylindriques à axe évidé etc.
Ces machines fonctionnent généralement avec des moteurs thermiques alimentés au gaz pour les petites et moyennes et au gasoil pour les grosses. Les petites unités peuvent aussi être à moteur électrique avec une alimentation par batteries.
Les éléments d'un chariot élévateur (agrandir)
Un chariot élévateur typique est généralement composé des éléments suivants :
Exemple de plaque de charge d'un chariot élévateur
A forklift truck , a lift truck or a forklift is a powered industrial truck used to lift and transport materials, normally by means of steel forks inserted under the load. Forklifts are most commonly used to move loads stored on pallets . The forklift was developed in the 1920s by various companies including the transmission manufacturing company Clark (today known as Clark Material Handling Company ) and the hoist company Yale & Towne Manufacturing (today known as Yale Materials Handling Corporation)  . It has since become an indispensable piece of equipment in manufacturing and warehousing operations.
Design types Top
There are many national and/or continental associations related to the industrial trucks. The three major ones are the Industrial Truck Association (North America), the Fédération Européenne de la Manutention (Europe), and the Japan Industrial Vehicles Association (Japan). There are many significant contacts among them and they have established joint statistical and engineering programs. One program is the WITS (World Industrial Trucks Statistics) 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 the Class System , which all the major manufacturers adhere to. Following is the list of the more common truck types, from the smallest to the biggest:
For a common (North American) reference, Home Depot , Lowes and Rona generally employ reach trucks inside the store and "traditional" forklifts when the store is closed. Most employees of such warehouse stores will happily explain the differences between the machines.
A typical forklift may be generally described as follows:
Control and capability Top
Forklift trucks are available in many variations and load capacities. In a typical warehouse setting most forklifts used have load capacities of around one to five tons, though machines of over 50 tonnes capacity have been built and operated.
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. Some machines also allow the operator to move the tines and backrest laterally (side-shift), allowing easier placement of a load. To aid the handling of skids that may have become excessively tilted and other specialty material handling needs, some forklifts are fitted with a mechanism that allows the tines to be rotated. In addition, a few machines offer a hydraulic control to move the tines together or apart, removing the need for the operator to get out of the cab to manually adjust for a differently sized load.
Roll and barrel clamp attachments for handling barrels, kegs, or paper rolls also have a control to operate the clamp pads that grab the load, such attachments also usually have a rotate function so that a vertically stored paper roll can be inserted into the horizontal intake of a printing press.
In some locations (such as carpet warehouses) a long metal pole is used instead of forks to lift large rolls. Similar devices, though much larger are used to pick up 40 tonne metal coils.
Another variation, used in some manufacturing facilities, utilizes forklift trucks with a clamp attachment that the operator can open and close around a load, instead of forks. Products such as cartons, boxes, etc., can be moved with these trucks. The product to be moved is squeezed, lifted, and carried to its destination. These are generally referred to as "clamp trucks".
Skilled forklift operators annually compete in obstacle and timed challenges at regional forklift rodeos .
Forklift safety Top
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. The B56 standard is now a free download from the ITSDF website .
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 many have rear-wheel steering. While this increases maneuverability in tight cornering situations, it differs from a driver's traditional experience with other wheeled vehicles 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 will be 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 must not be used as a personnel elevator without the fitting of specific safety equipment, such as a "cherry picker" or "cage". Additional safety considerations are detailed in the applicable Occupational Safety and Health Administration (OSHA—United States) and Health and Safety Executive (HSE—United Kingdom) rules, and lift truck operators must be trained and certified.
Today's market Top
|English | Accueil | Réparation | Entretien | Inspection | Equipements | Contact | Profil