Parts Of A Forklift
Forklifts are complicated. If you don't know the difference between a load backrest and a forklift carriage, the relative benefits of simplex vs duplex masts, or the OSHA regulations regarding overhead guards, you can easily end up buying inappropriate equipment.
Use my simple guide to familiarize yourself with all the most important components of a forklift truck, from wheels and tires to the range of accessories used to increase the versatility of these amazing machines.
Forklift Mast
Consisting of the forks and hydraulic lifting mechanism, including the lift cylinder, the mast is found at the front of the forklift and is very much the business end.
As the mast is responsible for holding and elevating the load, the right type of mast for your operational requirements is vital.
There are two main types of mast, standard and "full free lift".
The key difference is that, with a simpler standard mast system, lifting the load also raises the inner section of the mast, increasing the overall effective height of the forklift.
This can be problematic in working environments where overhead space is limited.
A full free lift uses a central hydraulic mechanism to raise the load without an overall height increase, which means more maneuverability but can reduce the operator's visibility due to the placement of the mechanism.
Masts are also described in terms of simplex (single), duplex, triplex, or quad variations. Essentially, the simplex mast is a standard mast, the duplex is a full free lift, whilst the triplex and quad types allow loads to be lifted higher than the initial height of the forklift itself and often require specialized operator training.
Go to our forklift mast page for full details.
Tilt Cylinder
The tilt cylinder of a forklift is a push-and-pull hydraulic system that allows the forklift mast to be actively tilted forward or backward by the operator. This helps with initially engaging the load and then shifting the load center of mass backward to improve stability. A tilt cylinder will be smaller than the main lift cylinder as it operates under a lower load.
Most forklifts use a dual tilt cylinder system, with a separate cylinder placed in line with each of the stationary rails on the mast. This prevents the lifting assembly from twisting during the tilting process, which would cause a loss of stability and undue stress on the mast assembly.
Forklift Counterweight
The counterweight of a forklift refers to weight purposefully distributed towards the rear of the machine to balance out the effect of a load at the front. Without a counterweight, the capacity of a forklift would be greatly reduced as a heavy load would cause the truck to tip forward.
Counterweighting is partly achieved by building forklifts so that heavy components are placed near the rear e.g. the battery of an electric forklift. There are limits to this design approach as these elements only weigh so much, so an extra counterbalance is also added.
The counterweight takes one of two main forms. Bulk-type counterweights consist of hollow sections on the rear of the chassis which are filled with lead to create a fixed weight. Stack-type counterweights have a base plate onto which metal plates or canisters are stacked, forming an adjustable counterweight system that can be increased or decreased depending on the loads to be lifted.
In addition to designed-in rear weight distribution and metal counterweights, some forklifts use rear tires filled with a particular saltwater solution to further increase the overall rear end mass.
Load Backrest
A forklift load backrest is an upright steel frame designed to prevent the load or parts of a stacked load from falling backward, especially when elevated above the top of the mast rails. The use of a backrest is an OSHA requirement for most types of forklift operations.
There are two fitting systems for forklift backrests, either slip-on or bolt-on. As the names suggest, slip-on backrests are attached by sliding on over a fixed post, whereas bolt-ons are bolted to fitments on the mast frame.
Backrests come in various sizes, especially in terms of height. Although there is a temptation to opt for a high version to facilitate taller loads, this may not be appropriate in work settings where overhead clearance is limited.
Forklift Forks
Forklifts have a pair of forks, attached to the carriage and used to raise and lower a load. That's pretty much that, right? Well no, not really.
There are actually several types of forks used depending on the application and, although many of them look similar to the casual observer, the differences are all-important. The basic industry-standard forks are known as ITA forks and feature a hook-type attachment mechanism.
There are 5 classes (I, II, III, IV, and V) of ITA forks, relating to the load capacity of the forklift on which they are to be used. Folding forks, which can be folded up flush against the forklift carriage to allow maneuverability in tight spaces.
Aside from these, there are tapered lumber forks, designed to slide under or in-between stacks of wood or sheet materials. Block forks fit through the holes in breeze blocks or other common construction materials, whilst cargo forks feature rollers and are used for loading/unloading cargo where roller decks or conveyors are in use. There are even elongated and padded marina forks for transporting boats without damaging them.
Forklift Attachments
Aside from the forks for which they are named, there is a whole range of different pieces of equipment that can be attached to the carriage, making a forklift a much more versatile tool than just for lifting palleted loads.
Bucket attachments allow forklifts to collect and move loose material. There are also several specialized varieties, such as bucket-and-hopper assemblies for concrete work.
Clamp attachments can be used for handling cylindrical objects such as oil barrels or hay bales. These improve security and control, especially when handling drums of potentially hazardous chemicals. Some of these include tipping mechanisms to facilitate the controlled pouring out of liquid or granular contents. There are also flat-sided "carton clamps" used for manipulating boxed loads.
Lifting hooks and boom/jib attachments are added to forklifts when loads need to be suspended from above rather than lifted from below.
There is almost no end to the uses you can put a forklift to with the right attachment, familiarizing yourself with the available products can save you from forking out unnecessarily for several more task-specific vehicles.
See our forklift attachments page for further information.
Forklift Carriage
The forklift carriage is the support platform that links the forks (or other attachments) and backrest to the mast containing the lift cylinder. They are all of a relatively similar design and are divided into classes, based on the carriage height i.e. the distance between the upper and lower fork bars, and which affect the lifting capacity of the forklift.
A Class 1 carriage (13" carriage height) is typically only rated for light operations up to a maximum of just over 2,000lbs, whereas a Class 5 (approximately 29") will handle loads in excess of 24,000lbs.
Forklift Capacity Plate
A forklift's capacity plate or data plate is a printed metal sheet on the chassis providing key information about the forklift. In addition to the lifting capacity (as the name suggests), the data plate will also include: model number, mast type, service weight, fuel type, recommended tire sizes, treads, and pressures, back tilt angle, and details of pre-installed attachments. There should also be a diagram showing key points of load distribution.
Forklift Overhead Guard
The overhead guard is a reinforced cage forming the roof of the cab, designed to protect the forklift operator from falling loads. Both OSHA and ANSI safety standards require all forklifts to be fitted with a suitable overhead guard, designed and tested with the forklift capacity in mind.
Forklift Cab
The forklift cab is the enclosure in which the operator sits whilst driving the forklift.
As a minimum, this consists of the overhead guard and an outer frame, helping to protect the operator from injury in case of a forklift accident (primarily either collision or falling load).
However, for forklift operators working in outdoor environments and especially adverse weather conditions, a full enclosure cab is a must. These encase the metal frame in toughened glass, providing protection from the elements without significantly compromising visibility.
With an enclosed cab other comfort options also become available such as heating or air-conditioning. These allow operators to work for longer in a wide range of temperatures without discomfort affecting their focus and creating a safety hazard.
Forklift Battery
An electric forklift is powered by its battery, requiring a fairly specialized, high-capacity unit. The two main types used are traditional lead-acid batteries and the newer lithium-ion systems. Lead-acid batteries are large and use liquid-filled cells which need regular topping up in order to operate efficiently. Lithium-ion batteries, by contrast, are more compact, require zero liquid maintenance, and have a better usage to charging time ratio.
The modern lithium-ion units can be expensive to buy but are significantly more cost-effective in the long term than their outdated lead-acid counterparts.
To see a breakdown of the 6 types of batteries, check out our forklift battery page.
Forklift Tires
There are three types of forklift tires, each suited to different applications: pneumatic (air), pneumatic (solid), and cushion tires.
Solid pneumatic tires are the most popular type on the market and, being made of solid rubber, have excellent durability. However, they are very hard and do not provide comfort or a smooth ride over uneven surfaces.
Cushion tires are also solid rubber but smaller and fitted directly to the wheel without rims. Their size and construction give them the best maneuverability over indoor flooring but can cause difficulties over any rough terrain.
Air-filled pneumatic tires are the most versatile, being suitable for indoor or outdoor environments including gradients and uneven surfaces. Their main drawbacks are a shorter life span than the other two types and limitations to loading capacity.
Tim Postlethwaite // Staff Writer