The TYWZ2-300 is the second-generation, modernized version of the TYW foot-hydraulic drum brake. Where TYW-315 is the "classic big-wheel" model, TYWZ2-300 is the refined Ø300 standard: optimized 12:1 pedal leverage, self-adjusting wear linkage, card-lock lining, and a smaller Ø300 envelope that fits legacy ZWZ/JB-ZQ foundations.
It is the only zero-power brake in the lineup - purpose-built for sites where electric, pneumatic, and even hydraulic power are unavailable, unreliable, or undesirable:
Underground mines - battery loco, man-riding trolley, skip stop
Track / rail cars - hand-pushed transfer, maintenance trolley
Field & remote - portable winch, logging yard, desert pipeline
Legacy crane end carriage - retrofit of 1980s gantry / bridge crane travel
Backup / emergency hand brake - paired with a power brake as dead-man backup
⚠️ What it is NOT: TYWZ2-300 is NOT for automated PLC control, NOT for high-frequency cycling (>~6 cyc/min sustained), and NOT a service brake for high-speed vehicles. It is a parking, holding, and low-speed stopping brake operated by a human foot. For automated lines, see YW / QW / JZ / MWZ electro-actuated models.
⚙️ 2. Technical Specifications
| Parameter | Value |
|---|---|
| Model | TYWZ2-300 |
| Brake Type | Normally closed, spring-applied, foot-pedal hydraulic release |
| Brake Wheel Diameter | Ø300 mm |
| Rated Braking Torque | ~400–500 N·m (configuration-dependent: pedal ratio × cylinder area × spring force)* |
| Pedal Leverage Ratio | ~12 : 1 (hydraulic amplification) |
| Pedal Travel (Normal / Max) | 120 mm / 160 mm |
| Release Stroke (Normal / Max) | 3 mm / 5 mm |
| Shoe Retraction | 0.6 mm (self-equalizing, auto-compensated) |
| Actuation Medium | Brake fluid (DOT-4 or mineral oil, per manual) |
| External Energy Required | 0 W / 0 scfm / 0 bar |
| Release Action | Foot pedal down → hydraulic push → shoes open |
| Engage Action | Foot off → spring → shoes clamp (dead-man) |
| Response | ~0.3s engage / ~0.4s release (human-limited) |
| Lining | Asbestos-free, card-lock, self-adjusting wear |
| Wear Compensation | ✅ Built-in self-adjust (upgrade vs TYW) |
| Ambient Temp. | -25°C to +50°C (std), -40°C low-temp seal kit |
| Standards | JB/ZQ 4388 legacy mounting dims, JB/T 7685 ref. |
| Mounting | Horizontal base, left/right interchangeable, A≈300mm |
| Options | Hand-lever conversion, remote pedal, low-temp kit, corrosion paint, Ø300 wheel |
