Rexroth A4VG axial piston pump lowers emissions for high-performance travel drives used in mobile equipment

Sept. 23, 2008
Bosch Rexroth has redesigned its high-pressure variable pump A4VG for closed circuit applications. With increased power density, the new Series 40 helps mobile equipment manufacturers comply with stricter worldwide emission regulations.The nominal pressure of the new series has increased by 700 psi to 6500 bar and nominal parameters have been adapted to counteract the reduced speed of the diesel engine and therefore lower input flow rates. Nine nominal parameters, which meet the new requirements, make it easy to choose the new axial piston pump with swashplate design for any application. The redesigned pump case provides manufacturers with a variety of ways to include sensors, such as for monitoring swivel angle, high pressure, and rotational speed. The extensive and modular range of control units provides the optimal solution for every application. Rexroth also completely redesigned the pump case, focusing on functionality and flexibility. A new bowl-shaped design avoids high-pressure transitions at sealing points, with some sealing points being eliminated entirely. Rexroth has also relocated the high-pressure ports to optimize arrangement of the hydraulic lines. If service is required, the new series uses connections for the O-ring seals to ensure all threads are leak-tight.The new A4VG and the newly developed Series 71 of the Rexroth A6VM axial piston variable motor form an ideal combination with increased power density for hydrostatic travel drives.