Hydrostatic transmissions have become the gold standard for the heavy machinery mining industry, due to its high output capacity, fuel consumption optimization, stability and safety profile.
Ideal for off-road machinery not exceeding 20 km/hour[i], they are typically structured as a hydraulic pump and hydraulic motor.
The vehicle’s motor actions the hydraulic pump, which in turn sends oil to the hydraulic motor with varying flows and pressure. The hydraulic motor turns that oil pressure into motor energy, allowing the machine to move. The oil then returns to the pump (closed circuit). The simpler set-up allows for fewer components in the system, and thus increases its reliability.
Hydrostatic transmission (closed circuit)
Hydrostatic transmission: more efficient & cost-efective underground
- Unlike mechanical or hydrodynamic transmissions, hydrostatics can provide you with a steady power curve without peaks and valleys[ii], which translates into a smoother operation even at low speed[iii].
- The system’s variable drive reduces driver workload as tractive power is available throughout the speed range without interruption. Its intuitive operability means it is more user-friendly, translating into higher productivity.
- Similarly, it can cut down the vehicle’s fuel consumption and noise emission, both of which are key as tougher EU legislation sets in.
- Its simplicity eliminates the associated costs of maintenance and operation of elements such as the clutch and the gearbox.
- In addition, all the components in the hydrostatic transmission are independent of each other, so a malfunctioning piece can be easily identified and replaced.
At Putzmeister Underground, our portfolio of underground transport machines boasts the addition of Integrated Continuously Variable Drive© (ICVD). These typically consist of a gearbox, hydraulic motor and control unit, and allow continuous drive with a conversion range of zero to maximum transport speed without interrupting the tractive force.
This transmission system is present in Putzmeister Underground´s Mixkret 4, Mixkret 5, Cemkret 8, and Minelift 4; which makes them particularly attractive for underground use, where safety requirements are particularly stringent.
[i] Ravi Bhushan Singh, Roshan Kumar & Jayanta Das, “Hydrostatic Transmission Systems in Heavy Machinery: Overview”, International Journal of Mechanical and Production Engineering, Volume 1 Issue 4, October 2013, http://iraj.in/journal/journal_file/journal_pdf/2-15-139047710947-51.pdf
[ii] Wolfgang Adamek, “Continously Variable Drive (ICVD®) Innovation for Manufacturers of Self-propelled Farm and Construction Machinery”, Landtechnik 2 2006,