The most common forklift type with a counterweight at the rear for lifting loads in front.
Detailed Definition
A counterbalanced forklift carries its load on forks in front of the front wheels, with a heavy counterweight at the rear that keeps the truck from tipping forward. It has no outriggers or straddle legs, so it can drive straight up to loads, into trailers and onto docks. Counterbalanced trucks come in electric (ITA Class I), internal combustion cushion tire (Class IV) and internal combustion pneumatic tire (Class V) versions. Capacity is shown on the data plate at a stated load center, often 24 inches on US trucks.
Stability and the load center
A counterbalanced truck works like a seesaw with the front axle as the pivot. The heavier the load, and the farther its center of gravity sits from the mast, the more it tries to tip the truck forward. That is why rated capacity applies only at the stated load center and lift height. Longer loads, attachments such as clamps or side shifters, and high lifts all reduce the actual capacity. The data plate, updated for any attachment, is the reference. Tilting forward with a raised load and turning with the load high are common causes of tipovers.
Choosing power and tires
- Electric trucks suit indoor work, produce no exhaust and run quietly, with lead-acid or lithium-ion batteries
- LP gas trucks refuel quickly and are common for mixed indoor and outdoor work with adequate ventilation
- Diesel trucks are generally used outdoors
- Cushion tires suit smooth indoor floors; pneumatic tires suit rough yards
Operators must be trained and evaluated under OSHA 29 CFR 1910.178, with a performance evaluation at least once every three years.
Daily checks before use
OSHA requires industrial trucks to be examined before being placed in service, at least daily, and defects affecting safe operation to be corrected before use. Typical pre-shift checks cover forks, chains, mast, tires, brakes, steering, horn, lights, fluid leaks and the data plate.
Related Glossary Terms
Frequently Asked Questions
Why does a forklift's capacity drop with an attachment or a long load?
Capacity is calculated at a specific load center, the distance from the fork face to the load's center of gravity. An attachment adds weight and pushes the load farther forward, and a long or deep load moves its center of gravity forward too. Both increase the tipping force about the front axle, so the safe capacity falls. The truck's data plate must be updated by the manufacturer or dealer to show capacity with each attachment.
Is a counterbalanced forklift suitable for narrow aisles?
Usually not for very narrow aisles. Because the truck must turn its full length to face the rack, counterbalanced forklifts generally need wider aisles than reach trucks or turret trucks. They are well suited to docks, trailer loading, yards and wide-aisle storage. If you are designing rack aisles, size them from the truck manufacturer's right-angle stacking dimension for your load, rather than a general rule.