load capacity diagrams
Reading the load diagram - Example 1
Table of contents
definition
The load capacity is a performance term for industrial trucks , such as manual and electric high-lift trucks and forklift trucks , and refers to the weight of a load that the device can transport while complying with safety standards.
This is indicated by a graphic representation, the so-called load capacity chart or load center chart, which shows the actual load capacity for the application . This can be used to determine whether a certain load can be safely moved to a certain height. The nominal load capacity is indicated on the type plate and in the load capacity diagram of the industrial truck, which differs from the actual load capacity as follows:
- Nominal load capacity: The value of the nominal load capacity only applies to a specific lifting height and a specific load center , i.e. a defined distance between the back of the fork and the load. This can be found on every type plate of a high lift truck. However, this is a theoretical value that is mainly used to compare different models.
- Actual load capacity: This value is the relevant value in daily work and can be caused by a lifting height that deviates from the norm or by a different load center of gravity. The actual load capacity can be read from the load capacity diagram, i.e. which weight can be moved safely up to which height.
The system consisting of the high lift truck and the load basically behaves like a seesaw and is subject to leverage. The side with the vehicle and the driver must always be significantly heavier than the side with the load, otherwise it would tip over. When lifting, the load's center of gravity moves away, so the load moves outwards on the seesaw, which is why the increasing height results in a lower load-bearing capacity.
Please note that the attached load capacity diagrams apply only to normal operating conditions, such as driving on level ground, driving with the load in a lowered position and stacking with the mast upright.
Reading the load capacity diagram correctly
The diagram shows at a glance which weight can be moved safely up to which height. The load capacity is linked to the lifting height and load centre of gravity.
- Lifting height: The lifting height of a high lift truck or forklift is the maximum height of the forks . It indicates how high the goods can be lifted.
- Load centre of gravity: The distance from the back of the fork to the centre of the load , assuming that the load is evenly distributed and therefore in the middle of the pallet. The load centre of gravity is usually specified by the manufacturer as 500 or 600 millimetres and can be found in the technical data of the device.
The diagram shows the permitted load capacities on the left and the lifting heights on the right. The lower axis shows the distances between the load centre of gravity and the back of the fork. The falling lines show that the possible load capacity decreases steadily as the distances become larger. This can be explained more easily using the following examples.
Example 1
reading the lifting heightThe load capacity is 1500 kilograms, the load center of gravity is 600 millimeters from the back of the forks. The current lifting height can be read along the diagonal line on the right in the diagram: 2500 millimeters. The load on the forks of the electric high lift truck cannot therefore be lifted higher than 2.5 meters, otherwise the device will tip over.
The principle also works the other way around, namely when reading from right to left. This procedure is used when the maximum lifting height and the load center of gravity are given, but the maximum load capacity is still undetermined.load capacity diagram as a table
In this example, the lifting height should be 2.5 meters, and the load center of gravity is a little further away this time, at 650 millimeters. On the right-hand scale, you go from the lifting height of 2500 millimeters along the diagonal line until you cross the line of the load center of gravity at 650 millimeters. This shows the maximum load capacity for the required lifting height: 1400 kilograms. If a higher weight is to be loaded, the load must be distributed across several pallets or stowed on a lower shelf.
Note: The values refer to a load centre of 600 millimetres.
| Possible lifting height | load capacity |
|---|---|
| Up to 2500 mm / 2.5 m | Maximum 1500 kg |
| Up to 3000 mm / 3 m | Maximum 1300 kg |
| Up to 3300 mm / 3.3 m | Maximum 1170 kg |
| Up to 3500 mm / 3.5 m | Maximum 1100 kg |
| Up to 4500 mm / 4.5 m | Maximum 700 kg |
| Up to 5000 mm / 5 m | Maximum 500 kg |
| Up to 5600 mm / 5.6 m | Maximum 350 kg |
