AA4VG90HD3D1/32R-NSF52F001D

The AA4VG90HD3D1/32R-NSF52F001D variable pump is produced by Bosch Rexroth for the AA4VG Variable Pumps series. It is intended to deliver adjustable hydraulic flow in closed circuit drives used in mobile or industrial automation. The maximum geometric displacement of 90 cm³ per revolution defines the largest volume of fluid the rotating group moves each cycle, allowing high output at low speeds. With a nominal speed of 3050 rpm the pump maintains continuous operation in typical drive loops. At that speed and full displacement it supplies 275 liters per minute, matching medium-size actuator demands. A nominal pressure rating of 400 bar sets the continuous load the housing and rotating assembly can withstand. At 400 bar the pump can deliver 183 kW, enabling high power density in compact transmissions. The corresponding torque at that pressure is 573 Nm, supplying sufficient shaft force for direct coupling to diesel engines or electric motors. The clockwise rotation direction standardizes installation on prime movers that turn in that orientation.

For low pressure replenishment the integrated boost stage displaces 19.6 cm³ per revolution, ensuring the closed circuit remains charged during transient demand. The pump starts to build flow from 500 rpm, so control systems can idle at low engine speeds without cavitation. Intermittent peaks up to 3800 rpm are permitted for short durations, while a continuous limit of 3300 rpm protects bearings from excessive velocity. The rotating assembly resists up to 18000 rad/s² of angular acceleration, allowing rapid speed changes in dynamic machine cycles. Maintaining structural integrity at this rate of change keeps volumetric efficiency stable. A maximum pressure ceiling of 450 bar provides margin for brief overload events without structural damage. The mass moment of inertia of 0.0149 kg·m² minimizes drive train stress during acceleration and deceleration. The low inertial load helps prime movers achieve target speed with less starting torque. Finally, a 1.5 liter case volume gives room for internal oil circulation and heat dissipation, stabilizing temperature in extended duty.