A4VG71DA2D2/32R-NZF02F001SQ-ES Rexroth Closed Circuit Pump 71 cm³ 400 bar

Product Overview

The A4VG71DA2D2/32R-NZF02F001SQ-ES and A4VG71DA1D2/32R-NAF02F001BP belong to the Bosch Rexroth A4VG series of closed-circuit variable displacement axial piston pumps. Featuring a swash-plate design for hydrostatic closed-circuit transmissions, flow is proportional to drive speed and displacement and is infinitely variable. Swivelling the pump over centre smoothly changes the direction of flow. Fully interchangeable with genuine Rexroth units, these pumps enable direct drop-in replacement without modification to mounting interfaces or piping. Every unit undergoes 100% simulated operating-condition testing to ensure high efficiency and reliability under high pressure.

Technical Specifications 

• Model: A4VG71DA2D2/32R-NZF02F001SQ-ES / A4VG71DA1D2/32R-NAF02F001BP
• Displacement (Vg max): 71 cm³/rev
• Continuous / Rated Pressure: up to 400 bar
• Peak / Intermittent Pressure: up to 450 bar
• Continuous Max. Speed (at Vg max): 3300 rpm
• Limited Max. Speed: 3600 rpm
• Intermittent Max. Speed: 4100 rpm
• Minimum Speed: 500 rpm
• Control Type: Variable (DA speed-related automatic control, etc., code dependent)
• Design: Swash-plate axial piston, closed circuit (with integral boost pump)
• Weight: approx. 50 kg
• Brand / Series: Bosch Rexroth A4VG closed-circuit variable piston pump

Key Technical Advantages

1. Closed-Circuit High-Pressure Design: Continuous rating of 400 bar and peak of 450 bar, optimized for hydrostatic transmissions, deliver high power density in a compact package.
2. Infinitely Variable Displacement & Bidirectional Flow: Displacement is steplessly adjustable from 0 to Vg max. Crossing centre smoothly reverses flow direction, ideal for reversible drive systems.
3. Integral Boost Pump & Safety Valves: Built-in boost pump supplies make-up and control oil. Dual high-pressure relief valves protect the transmission from overload, enhancing system reliability.
4. Versatile Controls & High Efficiency: Supports hydraulic, electric proportional, speed-related and other control options. Optimized swash-plate geometry maintains high volumetric efficiency and low noise.
5. True Interchangeability & Long Service Life: Fully compatible with OEM mounting dimensions and interfaces. High-load bearings and precision manufacturing ensure reliable long-term operation.

Application Areas

• Travel drive systems on construction machinery (excavators, loaders, rollers)
• Agricultural and forestry equipment hydrostatic transmissions
• Port and material-handling equipment
• Industrial closed-circuit hydraulic drive systems
• Any mobile or stationary application requiring bidirectional variable control

Expert Maintenance Tips

1. Ensure proper drive-shaft alignment during installation; use a flexible coupling and avoid excessive radial/axial loads. Verify correct closed-circuit piping connections.
2. Use anti-wear hydraulic oil meeting ISO cleanliness and viscosity requirements; system filtration should be at least 10 μm. Thoroughly bleed air and check case and boost pressure before initial start-up.
3. Regularly monitor boost pressure and case drain to prevent cavitation or over-pressure. Verify control signals and relief valve settings.
4. During service, inspect pistons, cylinder block and valve plate for wear; replace complete rotating groups when necessary. Store long-term units in a dry environment and rotate the shaft periodically.