The YW-E200/E50A is a two-step electro-hydraulic drum brake from the YW-E series, integrated with the E50A electro-hydraulic thruster as its core drive component. It features a 200 mm drum diameter, dual-stage braking torque output (low-speed precise braking + emergency high-torque braking), and a normally closed safety design. Optimized for equipment requiring stepwise speed control and reliable emergency braking, it is widely used in cranes, hoists, conveyors, and metallurgical auxiliary machinery. Below are its core parameters, working principle, key features, installation specifications, and typical applications:
1. Core Parameters
| Parameter Category | Specific Values |
|---|---|
| Product Model | YW-E200/E50A |
| Brake Type | Two-step electro-hydraulic drum brake (normally closed) |
| Drum Diameter | 200 mm |
| Drum Width | 80 mm |
| Braking Torque (Two-Step) | 1st step: 630–1000 N·m (precision braking); 2nd step: 1600–2500 N·m (emergency braking) |
| Matching Thruster | E50A two-step electro-hydraulic thruster |
| Thruster Rated Thrust | 50 kN (E50A) |
| Thruster Rated Stroke | 50 mm (E50A) |
| Thruster Rated Voltage | 380V three-phase AC (optional 220V AC) |
| Thruster Rated Power | 2.2 kW (E50A) |
| Operating Frequency | ≤1000 cycles per hour |
| Braking Response Time | 1st step: ≤0.6 seconds; 2nd step: ≤0.4 seconds |
| Release Response Time | ≤0.7 seconds |
| Protection Class (Thruster) | IP55 |
| Operating Temperature Range | -20°C to 70°C |
| Equipment Weight | ≈95 kg |
| Compliance Standards | GB/T 18839-2019, JB/T 10960-2021 |
2. Working Principle
The brake realizes two-step braking through the E50A thruster's dual-pressure output and the brake's dual-spring group design, following normally closed logic:
2.1 Brake Release (Power-On Stage)
When the host equipment runs, the E50A thruster is energized and outputs primary hydraulic pressure (8–10 MPa). The push rod extends linearly, compressing the first-stage brake springs, and the brake shoes separate from the drum (clearance: 0.3–0.5 mm) to complete release.
2.2 Two-Step Braking Engagement
1st Step (Precision Braking): When the equipment needs to decelerate slowly, the thruster reduces hydraulic pressure to 4–6 MPa. The first-stage springs rebound partially, pushing the brake shoes to lightly clamp the drum, generating 630–1000 N·m torque for smooth speed reduction.
2nd Step (Emergency Braking): For emergency stop or load locking, the thruster is de-energized. Hydraulic pressure is fully relieved, and both first/second-stage springs rebound completely. The brake shoes clamp the drum tightly, outputting 1600–2500 N·m high torque to stop the equipment quickly.
Fail-Safe Braking: In case of power failure or thruster malfunction, both spring groups act simultaneously to achieve emergency braking within ≤0.4 seconds, preventing equipment runaway.
2.3 Safety Guarantees
The E50A thruster is equipped with F-class insulation and a thermal protector (triggers at 155°C) to avoid motor burnout.
A built-in pressure relief valve (max pressure ≤18 MPa) protects the hydraulic system from overpressure; automatic wear compensator maintains stable brake clearance.
