Dual brakes (redundant braking) are used when the risk level is high and a single brake is not considered sufficient for safety. On many cranes—especially heavy-duty, high-lift, or critical-process cranes—dual braking ensures that if one brake fails (wear, contamination, actuator fault), the second brake can still stop or hold the load. This is particularly common in ladle cranes, high-capacity gantry cranes, and applications involving personnel or extremely high consequence loads.
Dual brakes can be arranged in different ways: two independent brakes on the same shaft, a primary service/holding brake plus a secondary emergency brake, or a combination of motor brake and shaft brake. The key is independence: separate actuation paths, separate friction surfaces, and ideally separate monitoring.
When specifying dual brakes, consider synchronization and control logic. Poor coordination can cause uneven wear or shock engagement. Proper commissioning, periodic testing, and clear maintenance procedures are essential to ensure redundancy is real—not just “two brakes installed.”