A4VG250HD3D1/32R-NSD10F00 Rexroth Piston Pump 250cc 400bar

Product Overview

The A4VG250HD3D1/32R-NSD10F00 is a Bosch Rexroth A4VG Series Series 32 swashplate-type axial piston variable displacement pump. The A4VG Series is Rexroth’s core product line for closed-circuit hydrostatic drive applications, renowned for its high power density and rugged reliability, with displacements covering 28 to 250 cm³/rev. This model represents the largest displacement offering in the series, delivering a maximum displacement of 250 cm³/rev.

This model features HD3D control—Hydraulic Pilot Control, enabling remote, stepless displacement regulation via pilot pressure signals. 32R denotes the Series 32 design platform with Right-hand rotation (clockwise when viewed from the shaft end) configuration. NSD10F00 is the shaft, mounting flange, and port configuration code.

As a direct OEM-equivalent replacement solution for the Bosch Rexroth A4VG Series, this product offers complete in-situ interchangeability, strictly adhering to Rexroth’s original design specifications and mounting interface standards. Every unit undergoes 100% simulated duty-cycle testing, ensuring that key performance metrics—including volumetric efficiency, pressure-flow characteristics, and case drain flow at rated pressure and full displacement—meet or exceed original factory specifications.

Technical Specifications 

• Model Number: A4VG250HD3D1/32R-NSD10F00

• Brand Series: Bosch Rexroth A4VG Series (Series 32)

• Pump Type: Swashplate Axial Piston Variable Displacement Pump (Closed Circuit)

• Maximum Displacement: 250 cm³/rev

• Nominal Pressure: 400 bar (40 MPa)

• Maximum Peak Pressure: 450 bar (45 MPa)

• Maximum Speed: 1900–2400 rpm (application dependent)

• Control Type: HD3D – Hydraulic Pilot Control

• Rotation Direction: R – Right-hand (clockwise from shaft end)

• Design Series: Series 32

• Charge Pump: Integral built-in charge pump (20 bar)

• Charge Pump Displacement: 52.5 cm³/rev

• Case Volume: 6.3 L

• Moment of Inertia: 0.0983 kg·m²

• Mounting Type: Flange Mounting

• Housing Material: Cast Iron

• Hydraulic Fluid: Mineral Oil

• Weight: Approx. 95–100 kg(up to 156 kg depending on configuration)

Key Technical Advantages

1. Closed-Circuit Dedicated Design with High System Integration
The A4VG Series is specifically designed for closed-circuit hydrostatic applications, featuring an integral built-in charge pump (20 bar) that provides system replenishing oil, cooling flow, and control pilot pressure. This design eliminates the need for an external charge pump, significantly simplifying system layout and reducing installation space requirements and system costs.

2. 400 bar Nominal Pressure with 450 bar Peak Capacity – Industry Leading
The A4VG250 delivers a nominal pressure of 400 bar (40 MPa) with peak pressures up to 450 bar (45 MPa) . At 250 cm³/rev displacement, it outputs approximately 600 L/min theoretical flow and approximately 400 kW of hydraulic power, providing ample power reserves for ultra-heavy mobile equipment.

3. HD3D Hydraulic Pilot Control for Remote Precision Displacement Adjustment
HD3D control enables remote displacement regulation via pilot pressure signals, delivering stepless flow adjustment from 0 to 250 cm³/rev. By moving the swashplate through the neutral position, flow direction can be reversed for smooth, seamless forward/reverse transitions. This control approach is particularly suited for large mining and construction machinery requiring remote operation.

4. Multiple Safety Protection Mechanisms for System Reliability
The A4VG Series features two relief valves on each high-pressure side to prevent hydrostatic transmission (pump and motor) overload. The relief valves also function as charge check valves. A built-in pressure cut-off valve is standard equipment. Together, these triple protection mechanisms ensure system safety and reliability under extreme operating conditions.

5. High Power Density with Rugged Heavy-Duty Construction
The A4VG250 features a swashplate axial piston design that delivers exceptionally high power density within a compact footprint. The Series 32 design platform further optimizes rotating group components while maintaining high reliability. The pump is widely used on Caterpillar, Liebherr, and Komatsu large mining excavators (365C L, 374D L, 385C L, 390D L, R9250, PC1250, PC2000, etc.), as well as Wirtgen cold milling machines, Vogele asphalt pavers, and Bomag/Dynapac rollers.

Application Areas

• Ultra-Large Mining Excavators: Caterpillar 365C L/374D L/385C L/390D L, Liebherr R9250, Komatsu PC1250/PC2000, etc.

• Cold Milling Machines: Wirtgen W210/W220/W250, etc.

• Asphalt Pavers: Vogele Super 1900-3/Super 2100-3, etc.

• Rollers: Bomag BW226 DH-4, Dynapac CA6000, etc.

• Tunnel Boring Machines (TBM): Heavy-duty shield machine hydraulic systems

• Marine Hydraulic Systems: Large vessel deck machinery and steering gear systems

Expert Maintenance Tips

1. Model Confirmation & Pre-Installation Inspection: Prior to installation, confirm the complete model code as A4VG250HD3D1/32R-NSD10F00. This is a Series 32 right-hand rotation configuration—pay special attention to matching the rotation direction with the host machine PTO. The pump weighs approximately 95–100 kg (up to 156 kg depending on configuration)—ensure lifting equipment has adequate capacity. Manually rotate the shaft before installation to confirm smooth, obstruction-free rotation.

2. Closed-Circuit Air Purge & Charge: The A4VG Series is a closed-circuit design—ensure thorough system air purge before first start-up. Air in the closed circuit can cause cavitation, noise, and performance degradation. After start-up, run at low speed with repeated direction changes to purge air from both high and low pressure circuits.

3. Fluid Cleanliness Control: Closed circuits have stringent fluid cleanliness requirements. Use high-quality mineral hydraulic oil meeting Rexroth specifications with a minimum filtration rating of ISO 18/15. The A4VG250’s large displacement (250 cc) means higher flow rates and more demanding lubrication requirements. Complete system flushing is mandatory before initial start-up.

4. HD3D Hydraulic Pilot Controller Tuning: HD3D control regulates displacement via pilot pressure signals. During commissioning, set the pilot pressure range based on the host machine’s hydraulic system design and verify the proportional relationship between pilot pressure and displacement output meets specifications. Perform initial settings under no-load conditions, then gradually increase load to target operating conditions with fine adjustments.

5. Charge Pressure Verification: The A4VG Series features an integral built-in charge pump (20 bar). After first start-up, verify charge pressure is within specification range. Low charge pressure causes sluggish control response and inadequate piston/slipper lubrication; excessive charge pressure may cause system overheating.

6. Case Drain Port Positioning & Pressure Monitoring: During installation, ensure the drain port is positioned higher than the pump body to prevent oil starvation in the pump chamber after shutdown. Case volume is 6.3 L—ensure the drain line has adequate diameter. Install a pressure gauge on the case drain line for real-time monitoring to ensure case pressure remains within specifications.