Hydrostatic Braking Valve

The unloading brake valve for hydrostatic transmission systems combines the braking effect of the pedal with a hydrostatic unloading proportional valve. Pressing the pedal reduces—or even reduces to zero—the pump’s output flow to achieve braking for the whole machine, significantly reducing the load on the service brakes of heavy hydrostatic vehicles. This function is commonly known as “inch braking.” When the pedal is released, the hydrostatic system resumes normal output, the brakes are released, and the vehicle moves freely.

Features

1. Hydrostatic unloading proportional valve + reverse brake pedal valve (for vehicles with spring-applied, hydraulically released service brakes)
   
2. Hydrostatic unloading proportional valve + single-circuit brake pedal valve (for vehicles with single-axle spring-applied, hydraulically released brakes)
   
3. Hydrostatic unloading proportional valve + dual-circuit brake pedal valve (for vehicles with dual-axle spring-applied, hydraulically released brakes)
   
4. Hydrostatic unloading proportional valve typically set to 22 ± 2 bar, adjustable according to vehicle requirements
   
5. Output pressure of reverse brake valve and single/dual-circuit brake valves selectable within 20–200 bar
   

Operating Conditions

1. Working medium: Mineral-based hydraulic oil
   
2. Viscosity range: 2.8–380 cst
   
3. Hydraulic oil temperature range: −30 °C ~ +107 °C
   
4. Cleanliness: ISO 4406, class 18/16/13
   
5. Maximum input pressure: 210 bar
   

     For detailed technical specifications and drawing solutions, please contact us at suno_fr@sunotech.com.cn or leave us a message.