For heavy-duty forklifts, the braking system bears a significant load. The vehicle itself is already heavy, and the overall weight increases further when loaded. Under heavy loads, on inclines, or with frequent starts and stops, the braking system needs to handle even greater braking energy. Ordinary braking structures are not well-suited for long-term operation under such conditions.
Some heavy-duty forklifts use multi-disc wet brakes as their service brakes. Structurally, this differs from common disc brakes. Multiple sets of friction pads and brake discs are installed within a relatively enclosed brake chamber. During braking, braking force is generated through the interaction between the friction pairs, while the hydraulic fluid participates in cooling and lubrication.
- Why "multiple discs"?
Heavy-duty forklifts require significant braking force, but the overall vehicle structure cannot infinitely increase the brake size. Arranging multiple sets of friction pads within a limited space increases the effective friction area, allowing the braking system to achieve greater braking force. For large-tonnage vehicles, this structure is more suitable for braking requirements under heavy load conditions.
- "Wet" is also a crucial characteristic.
When a vehicle brakes, kinetic energy is converted into heat. The greater the braking load, the more heat is generated. The fluid in wet brakes helps dissipate the heat generated by friction, playing a role in controlling brake temperature rise. Thermal management of the braking system is particularly important in situations such as heavy-load downhill driving or frequent deceleration. Good heat dissipation helps reduce the adverse effects of high temperatures on braking performance.
The relatively enclosed structure of the brakes also reduces the ingress of external dust, mud, and other impurities. The working environment of construction machinery is usually not as clean as that of passenger cars. Ports, mines, stone quarries, and steelworks often contain significant amounts of dust and debris, making this structure necessary to withstand harsher environments.
It is important to note that service brakes and parking brakes are not the same thing.
Service brakes are primarily used for deceleration and stopping the vehicle during operation and require repeated use based on the driver's input. Parking brakes are used after the vehicle has come to a stop, primarily to keep the vehicle stationary.
Therefore, heavy-duty forklifts may employ different braking structures to handle these two functions separately. For example, the service brakes may use multi-disc wet brakes, while the parking brakes may use caliper disc brakes. The two systems are responsible for different operating conditions; this isn't a comparison of which braking method is better.
For heavy-duty forklifts, the braking system isn't a prominent feature on the specifications sheet. However, it affects the vehicle's deceleration and stopping performance under heavy loads. When purchasing equipment, in addition to considering engine power, rated load, and lifting height, it's also important to understand the structure of the service brake and parking brake based on the actual operating conditions.
