The YWZ4-500/E121 series electro-hydraulic drum brake is a heavy-duty, normally-closed braking device engineered for ultra-large-tonnage industrial equipment. It is exclusively matched with the E121 series electro-hydraulic thruster (e.g., ED121/6), delivering exceptional braking torque, reliable fail-safe performance, and automatic gap adjustment. Suitable for non-explosive general industrial environments such as large-scale cranes, heavy-duty conveyors, metallurgical rolling mills, and port bulk handling machinery, it ensures stable braking and precise positioning for high-load, high-intensity operations.
Core Technical Specifications
| Parameter | Standard Value | Notes |
|---|---|---|
| Rated Drum Diameter | 500 mm | Optimized for large-load equipment drum dimensions |
| Rated Braking Torque | 4000–8000 N·m | Adjustable via thruster thrust and spring preload; meets ultra-heavy load braking demands |
| Matching Thruster Model | E121 (e.g., ED121/6, YT1-125Z/10) | Electro-hydraulic thruster with rated thrust 12500 N |
| Brake Shoe Clearance | 1.0–1.5 mm | Automatically balanced by precision mechanical gap adjuster |
| Friction Lining Material | Non-asbestos high-temperature wear-resistant composite | Friction coefficient ≥0.38; low fading (≤12% at 250℃); heat capacity ≥1.2 kJ/(kg·℃) |
| Working Voltage | 380V/660V 3-phase AC | Compatible with industrial power grids; dual-voltage optional |
| Protection Class | IP54 | Dustproof and water-resistant, adaptable to humid/dusty workshop environments |
| Working Temperature | -20℃ to +55℃ | Stable performance under extreme temperature fluctuations |
| Lining Thickness (Original) | 16 mm | Replace when worn to ≤3 mm; wear-resistant design extends service life |
| Weight (w/o Thruster) | ~180 kg | Robust structure for heavy-duty operation; standardized mounting interfaces |
Key Structural & Functional Features
Heavy-Duty Fail-Safe Normally-Closed Mechanism
Spring-driven braking: High-strength disc springs provide constant, large clamping force when the thruster is de-energized, ensuring immediate emergency braking within ≤0.6 seconds on power loss or thruster failure-critical for ultra-heavy load equipment safety.
Electro-hydraulic release: The E121 thruster generates high hydraulic pressure to push the brake arms, overcoming strong spring force and separating brake shoes from the drum smoothly, avoiding impact on equipment during startup.
Precision Automatic Gap Adjustment
Equipped with a multi-link interlocking gap balancing device that automatically compensates for the clearance between brake shoes and the drum caused by lining wear, maintaining the gap at 1.0–1.5 mm. Eliminates manual adjustment workload and ensures consistent braking torque even after long-term use.
Durable & Wear-Resistant Design
Clip-on thickened friction linings: 16 mm original thickness with high-temperature resistant and wear-resistant composite material, suitable for high-frequency braking scenarios; quick replacement without disassembling the entire brake body, reducing maintenance downtime.
Corrosion-resistant reinforcement: Brake body adopts shot blasting + anti-corrosion spraying treatment; fasteners are hot-dip galvanized or made of stainless steel; self-lubricating alloy bushings on brake arm hinges-resisting corrosion and reducing friction for extended service life.
Safety Interlock & Stability Enhancement
Configurable explosion-proof limit switch (optional): Sends real-time brake release/closure signals to the host control system, preventing equipment startup before full brake release and avoiding misoperation.
Reinforced brake arm structure: Adopts integral forging process, with tensile strength ≥600 MPa, ensuring no deformation under ultra-large braking torque; optimized stress distribution design reduces vibration and noise during braking.
Working Principle
The brake operates in the spring braking + electro-hydraulic release mode, perfectly matching the E121 thruster's high-thrust performance:
Brake Release (Equipment Operation): When the host equipment starts, the E121 thruster is energized. Its motor drives the hydraulic pump to build high pressure, pushing the push rod to extend. The push rod acts on the reinforced brake arm, compressing the high-strength disc spring and separating the brake shoe from the drum-allowing the equipment to run smoothly.
Brake Application (Equipment Stop/Emergency): When the equipment stops, the thruster loses power. Hydraulic pressure dissipates rapidly, and the braking spring rebounds to pull the brake arm tightly, making the thickened friction lining clamp the drum evenly. The ultra-large braking torque quickly decelerates and stops the equipment, ensuring safe shutdown even under full-load conditions.
