Understanding the load capacity and load distribution of pallet jacks is crucial for safely and efficiently operating forklifts.
1. Load Capacity
Load capacity refers to the maximum weight a pallet jack is designed to safely lift and transport. It is typically measured in pounds (lbs) or tons and is clearly indicated on the forklift’s nameplate.
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Rated Load: This is the most important specification. It refers to the maximum weight the forklift can safely carry when the forks are at the standard lifting height (usually at a low or mid-position) and the load center is within a specified distance.
For example, if the nameplate states a rated load of 4,400 lbs with a load center of 20 inches, it means that when the load’s center is 20 inches away from the vertical part of the fork, the maximum weight it can carry is 4,400 lbs. - Load Center: This is the horizontal distance from the center of the load to the front surface of the vertical part of the fork. It’s a critical factor that directly impacts the forklift’s lifting ability. A longer or asymmetrical load will have a larger load center.
Never overload, as doing so can cause:
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Structural Damage: This includes damage to the frame, forks, deformation or breakage, and hydraulic leaks.
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Loss of Stability: Overloading can cause the forklift to tip over, leading to serious accidents.
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Brake Failure: Excessive weight can increase stopping distance or cause the brakes to fail.
2. Load Distribution
Load distribution refers to how the weight of the goods is positioned and spread across the forks. Even if the total weight doesn’t exceed the rated capacity, incorrect load distribution can still be dangerous.
Place the load center as close to the fork’s vertical section as possible:
The further the load center (or the center of gravity) is from the fork, the greater the tipping force created, and the forklift’s actual lifting capacity will decrease significantly.
Many forklifts have a chart on their nameplate that shows the actual capacity at different load centers. For example:
| Load Center (inches) | Maximum Weight |
|---|---|
| 20 inches | 5,500 lbs |
| 24 inches | 4,400 lbs |
| 31.5 inches | 3,300 lbs |
| 39.5 inches | 2,640 lbs |
Ensure the load is even and stable:
Ideal Situation: The load is evenly placed on a sturdy pallet, with the weight evenly distributed across both forks.
Dangerous Situations:
- Off-center Load: The load's center of gravity is shifted to one side of the fork. This can lead to uneven force distribution, making tipping more likely when turning or lifting.
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Unstable Load: If the load is stacked too high, unevenly, or not secured, it could shift or fall during movement.
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Oversized Load: Even if the weight is within limits, a large load can obstruct the operator’s view and affect the forklift’s stability.
In summary, load capacity is the "theoretical limit" of a pallet jack, while load distribution determines whether you can "safely reach this limit." Always prioritize safety—don’t overload or distribute the load unevenly. These are the golden rules for operating a pallet jack.