The YWZ8-315/E30A is a light-to-medium duty electro-hydraulic drum brake (315 mm drum diameter, paired with ED30/5A thruster), designed for working/parking braking of small-to-medium cranes, conveyors, and hoists, featuring automatic wear compensation and reliable fail-safe operation.
Core Specifications
| Parameter | Value |
|---|---|
| Drum diameter | 315 mm |
| Rated braking torque | 300 N·m (adjustable range: 125–300 N·m) |
| Matched thruster | ED30/5A (300 N thrust, 50 mm stroke) |
| Brake clearance | 0.8–1.2 mm (auto-compensated when worn) |
| Friction lining | Non-asbestos, thickness 14 mm (replace when ≤4 mm) |
| Operating system | Normally closed (spring-applied, electro-hydraulic released) |
| Ambient temp | -20 °C to +50 °C |
| Relative humidity | ≤90% |
| Weight | ~42 kg |
| Installation center height | 200 mm |
| Insulation class | B (thruster motor) |
| Action frequency | Up to 1200 times/hour |
| Standards | JB/T6406-2006, DIN15435 |
Structure & Working Principle
Structure: Reinforced brake frame + left/right brake shoes + high-stiffness return spring + automatic wear compensation mechanism + ED30/5A electro-hydraulic thruster + fixed base. Main hinge points use self-lubricating bearings for low friction and long life.
Fail-Safe Operation:
Power-on (release): Thruster motor activates, hydraulic pressure pushes the pushrod upward. Lever mechanism retracts brake shoes, compresses the return spring, and the brake releases.
Power-off (braking): Thruster loses power, pushrod retracts via spring force and gravity. Return spring rebounds, driving shoes to clamp the drum for stable braking.
Automatic Compensation: As liners wear, the built-in mechanism adjusts clearance automatically, maintaining consistent braking torque without manual intervention.
Key Advantages
Low-maintenance design: Automatic wear compensation reduces manual adjustment; self-lubricating hinges eliminate routine lubrication.
Reliable safety: Normally closed structure ensures immediate braking on power failure, preventing equipment drift.
Stable performance: Non-asbestos liners with stable friction coefficient (μ≈0.35–0.4) and good high-temperature resistance.
High action frequency: Up to 1200 cycles/hour, suitable for frequent start-stop applications.
Easy replacement: Snap-in liners allow quick change without disassembling the brake frame.
Applications
Primary: Working and parking braking for small bridge cranes, electric hoists, light-duty belt conveyors, and stackers in workshops, warehouses, and small ports.
Secondary: Braking for auxiliary mechanisms (e.g., slewing, luffing) of medium-sized lifting equipment in metallurgy, coal, and logistics industries.
Installation & Maintenance
Installation:
Mount on a rigid base to avoid vibration; ensure drum concentricity (runout ≤0.15 mm) and thruster pushrod alignment (no lateral force).
Connect thruster to 380 V 3-phase power; fill with ISO VG 32/46 hydraulic oil to the specified level.
Verify automatic compensation works; test braking/release flexibility before commissioning.
