Drive and control manufacturer Bosch Rexroth’s Hydrotrac GFT 8000 gearbox, which was launched earlier this year, enables an approximate 10% increase in drivetrain performance for larger mobile working machines, the company says.

Bosch Rexroth uses the newest versions of variable axial piston motors or fixed-displacement axial piston motors, which operate in either an open or closed circuit.

The mechanical planetary drives in these transmission units transfer the torque from the hydrostatic drive to the wheels or tracks.

Travel capacity is significantly improved as the higher fluid capacity of the motors and the higher hydraulic pressures, along with the exact matching with the two- and three-stage planetary drives, boost torques, and therefore, performance by about 10%.

At the same time, vehicle manufacturers can select a smaller nominal size to achieve the same output saving on installation space.

Ideal for use in harsh, rugged environments such as mining, the gearboxes have two- and three-stage combined planetary gearing with axial piston motors to match the needs of heavy and bulky mobile working machines such as trucks and excavators.

An optional internal brake reduces the installation space needed, but adheres to the safety specifications for worldwide roadworthiness certification.

The optional integrated multidisc brake requires minimal maintenance and is designed for protection against soiling, an added advantage when working in demanding environments. Also, when used in conjunction with Bosch Rexroth’s High Level Braking System, the brakes satisfy the exacting safety requirements for speeds up to 50 km/h.

Available through hydraulic components and systems supplier Hytec, these transmission units are based on a modular design.

All units are delivered as complete assemblies, ready for installation. As a result of the platform’s modular concept, original-equipment manufacturers can vary the drive torques and transmission ratios, closely matching them to the vehicle used.

Two models in the 8000 series, which achieve nominal torques of 20 kNm and 30 kNm, are available off-the-shelf, and an additional seven models are currently being rolled out to the market.