1. Material Performance Basis
The rated load of a polyurethane solid forklift tire is based on the performance of the material itself. Polyurethane materials have certain properties such as compressive strength, hardness and elastic modulus. When determining the rated load, manufacturers need to pass a large number of material performance tests. For example, a compression test is performed on polyurethane samples to understand the deformation of the material under different pressures. If the material deforms excessively or even breaks under a small pressure, the tire's load-bearing capacity will inevitably be limited. The hardness of the material will also affect the load. Polyurethane with higher hardness is less likely to be crushed when bearing weight and can bear relatively heavier loads. By accurately measuring these material performance parameters, the most basic data support is provided for determining the rated load.
2. Tire structure design considerations
The structural design of the tire has a key impact on the rated load. From the perspective of the carcass structure, the internal cord layer structure, the layout of the reinforcement ribs, etc. will affect the tire's load-bearing capacity. If the cord layer adopts a high-strength, multi-layer design, and the reinforcement ribs are reasonably distributed in the key stress-bearing parts of the tire, the tire can withstand greater pressure. For example, reinforcing ribs are set under the tread and inside the sidewall of the tire to effectively disperse the pressure caused by the forklift load. The pattern design is also important. A deeper and reasonably laid out pattern can increase the contact area between the tire and the ground to a certain extent, improve the friction and help disperse the pressure, thereby increasing the rated load of the tire.
3. Safety factor and operating conditions
To determine the rated load, the safety factor and the operating conditions of the forklift must also be considered. In actual operation, the forklift may face various complex situations, such as uneven roads, sudden acceleration and braking, etc. In order to ensure the safety of the tire in these situations, a certain safety factor needs to be set. Usually, this safety factor is determined based on industry standards and experience. For forklifts that often work in harsh road conditions, the safety factor will be increased accordingly, which means that the rated load will be relatively conservative. For example, for forklifts operating on potholes in warehouses or rough outdoor ground, the tires need to have sufficient load-bearing capacity margin to cope with sudden impact forces, so the rated load will be lower than forklifts operating on flat roads and in better operating conditions.
4. Testing and Verification Process
Finally, the rated load is determined through a rigorous testing and verification process. The manufacturer uses equipment that simulates forklift loads to load the tires in a laboratory environment. During the test, the load is gradually increased until the tire shows some kind of failure phenomenon, such as excessive deformation, material tearing, etc. By testing tires of different specifications and structures many times, combined with the aforementioned factors such as material properties, structural design, and safety factor, the rated load of each model of Polyurethane solid forklift tire is finally determined. In addition, during the actual production process, sampling inspections will be carried out to ensure that the tires produced can meet the rated load requirements.
