I. Working Principle
(The normally closed type is the main type, and the brake is activated when the pressure is lost)
The mainstream products adopt a normally closed structure that uses disc springs to apply force and hydraulic pressure to release the force. The structure is as follows:
Braking state: The hydraulic cylinder is de-pressurized, and the disc spring releases its elastic potential energy, pushing the brake caliper to clamp the wheel rim or brake disc, relying on friction to lock the wheel.
Release state: The hydraulic station supplies high-pressure oil (usually 8-10 MPa), and the piston recoils against the spring force, causing the friction plate to separate from the wheel, allowing the equipment to move.
Failure protection: In case of power failure, oil pipe rupture, or hydraulic failure, the device automatically applies the brake to prevent runaway.
II. Core Structure and Features
Core components: Disc spring hydraulic cylinder, clamp-type brake arm, asbestos-free friction pads, limit travel switch.
Safety interlock: The limit switch provides the brake position signal, and the equipment cannot be started when the brake is not released.
Protection level: Mostly IP65, with multiple seals to prevent dust, mud, and water from entering.
Response speed: Typical release ≤ 0.2 s, braking ≤ 0.1 s.
III. Typical Application Scenarios
Port machinery: Wind-resistant braking for tire cranes (RTG), container gantry cranes, face haulers, and loading/unloading bridges.
Industrial and mining open areas: Portal/bridge cranes, gantry cranes, heavy-duty factory rail vehicles.
Mining and construction machinery: Mining dump trucks, loaders, excavators, underground shovel loaders.
Others: Metallurgical vehicles, hoists, belt conveyors, ropeway cable cars.
When installing, prioritize the placement of the passive wheel. The driving wheel can be used in combination to enhance the wind resistance level.
IV. Common Faults and Troubleshooting
Insufficient braking force: Oil leakage, air intake in the oil circuit, oil seal damage on the hub causing the brake disc to be smeared with oil, friction plate burnout.
Brake drift: Unequal braking torque on both sides, mostly due to oil contamination on the brake disc or stuck piston of the distributor pump.
Brake sticking: Difficulty starting, overheating of the brake disc, often caused by damage to the dust seal allowing water to enter and corroding the piston.
Unable to open: Oil tank low on oil, oil pump damage, electromagnetic valve stuck, loose relief valve (normal oil pressure is approximately 8-10 MPa).
