A4VG40DA1D8/32R-NSC02FXX5DP-S Rexroth Piston Pump

Product Overview

A4VG40DA1D8/32R-NSC02FXX5DP-S is a Bosch Rexroth A4VG Series 32 NG40 variable axial piston pump designed for closed-circuit hydraulic systems.

The A4VG Series 32 uses a swashplate variable-displacement architecture and is specified by Bosch Rexroth for 400 bar nominal pressure and 450 bar maximum pressure. The platform incorporates an auxiliary boost pump, high-pressure relief functions, pressure cut-off and multiple displacement-control options.

The key control designation DA1 identifies automatic speed-related control. Bosch Rexroth describes DA as a closed-loop control system primarily intended for travel drives. Pump displacement responds to drive-speed-related pilot pressure and system loading, allowing the hydraulic drive to adapt displacement to machine operating conditions.

The D code indicates pressure cut-off, while 8 identifies the fixed DA control-valve configuration with a hydraulic inch valve. R specifies clockwise rotation when viewed from the drive shaft.

The current public Bosch Rexroth code table does not fully decode the supplied XX5DP-S suffix character by character, so that portion should be verified against the original nameplate and material number rather than interpreted speculatively.

Technical Specifications

• Model: A4VG40DA1D8/32R-NSC02FXX5DP-S
• Brand: Bosch Rexroth
• Series: A4VG Series 32
• Pump type: Variable axial piston pump
• Circuit: Closed circuit
• Nominal size: NG40
• Maximum displacement: 40 cm³/rev
• Integrated boost-pump displacement: 8.6 cm³/rev at 20 bar
• Nominal pressure: 400 bar
• Maximum pressure: 450 bar
• Maximum pressure single operating period: 10 s
• Maximum cumulative operating period at maximum pressure: 300 h
• Maximum speed at Vg max: 4000 rpm
• Limited maximum speed: 4200 rpm
• Intermittent maximum speed: 5000 rpm
• Minimum speed: 500 rpm
• Flow at nnom and Vg max: 160 L/min
• Theoretical power at nnom, Vg max and Δp = 400 bar: 107 kW
• Theoretical torque at Vg max and Δp = 400 bar: 255 Nm
• Boost-pump nominal pressure: 25 bar
• Boost-pump maximum pressure: 40 bar
• Control: DA1 speed-related automatic control
• DA1 voltage: 12 V ±20%
• Pressure cut-off: D
• DA control valve: D8, fixed setting with hydraulic inch valve
• Rotation: Clockwise
• Seal designation: NBR with FKM shaft seal
• Drive shaft: ANSI B92.1a splined shaft, single-pump configuration
• Mounting flange: SAE J744 2-hole
• Port plate: 02
• Integrated boost pump: F
• Approximate weight without through drive: 31 kg
• Case volume: 1.1 L
• Rotary-group inertia: 0.0038 kg·m²

These values come from Bosch Rexroth’s official A4VG Series 32 technical data and type-code documentation.

Key Technical Advantages

Speed-Related DA1 Control

DA1 links pump displacement to drive-speed-related pilot pressure. As drive speed changes, the DA control modifies displacement, while increasing system load can cause the pump to reduce displacement and help prevent excessive engine loading.

400/450 bar Pressure Platform

The official Series 32 rating is 400 bar nominal and 450 bar maximum pressure. The 450 bar value is a time-limited maximum rather than a continuous operating rating.

High Flow Capability

With a maximum displacement of 40 cm³/rev and a rated speed of 4000 rpm at Vg max, the NG40 generates a theoretical 160 L/min flow. At 400 bar differential pressure, the documented theoretical power is 107 kW.

Integrated Boost Pump

The integrated 8.6 cm³/rev boost pump supports the closed-circuit charge and control-oil functions.

Pressure Cut-Off and Inching Function

The D8 configuration combines pressure cut-off with a fixed DA control valve and hydraulic inch valve, providing a compact control arrangement for travel-drive applications.

Engineering Material Note

Bosch Rexroth does not publish the exact steel grades or heat-treatment parameters for this specific configuration in the reviewed public documentation. It is therefore preferable to describe the engineering value through the precision swashplate/axial-piston assembly, control response, lubrication requirements and pressure capability rather than unsupported material claims.

Application Areas

Typical application categories include:

• Construction machinery travel drives
• Tracked mobile equipment
• Wheeled mobile machinery
• Road-building machinery
• Mining mobile equipment
• Agricultural machinery
• High-power hydrostatic transmissions

DA applications should be evaluated with the motor, engine and vehicle parameters as recommended by Bosch Rexroth.

Expert Maintenance Tips

• Maintain the low-pressure side at least 10 bar above case pressure.
• Keep continuous case-pressure differential at or below 2 bar under the specified operating condition.
• During cold start, keep viscosity ≤1600 mm²/s, pressure ≤50 bar and speed ≤1000 rpm for the specified maximum 3-minute period.
• Maintain optimum operating viscosity within approximately 16–36 mm²/s.
• Maintain hydraulic cleanliness of at least ISO 4406 20/18/15; when viscosity falls below 10 mm²/s, the cleaner 19/17/14 level is required.
• For replacement testing, reproduce the DA1 control chain from drive speed to pilot pressure and pump displacement rather than checking only static flow.