Facts About Forklifts
A forklift (also called a lift truck, a high/low, a stacker-truck, or a side loader) is a powered industrial truck used to lift and transport materials.
Truck Frame - is the base of the machine to which the mast, axles, wheels, counterweight, overhead guard and power source are attached. The frames usually 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.
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 part of the frame assembly.
Power Source - may consist of an internal combustion engine that can be powered by LP gas, gasoline or diesel fuel. Electric forklifts are powered by either a battery or fuel cells that provide power to electric motors. The motors 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 either hydraulically operated by one or more hydraulic cylinders or it may be chain operated with a hydraulic motor providing motive power. 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. These include sideshifters, rotator, carton clamps, multipurpose clamps, fork positioners, carpet poles, pole handlers, container handlers, roll clamps and many others.
Below is a list of common forklift attachments:
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.
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 - 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 slipsheet and draws the slipsheet onto wide and thin metal forks for transport. The attachment will push the slip sheet and load off the forks for placement.
Drum Handler - 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.