AA10VSO28DFR1/31R-VPA12N00 Rexroth A10VSO 28cc Variable Piston Pump

Product Overview

The AA10VSO28DFR1/31R-VPA12N00 and AA10VSO18DFR/31R-PPA12N00 belong to the Bosch Rexroth A10VSO Series 31 open-circuit variable displacement axial piston pumps. Featuring a swashplate design, flow is proportional to drive speed and displacement and can be steplessly adjusted via pressure-flow control (DFR/DFR1). Manufactured to exact original Rexroth dimensions, interfaces and control characteristics, these pumps offer complete interchangeability and can replace genuine A10VSO units without modification to mounting or piping. Every unit undergoes 100% simulated operating-condition testing to ensure pressure, flow, noise and response performance meets or exceeds OEM standards, making them ideal for industrial hydraulic systems demanding high reliability and long service life.

Technical Specifications 

• Model: AA10VSO28DFR1/31R-VPA12N00 (size 28) / AA10VSO18DFR/31R-PPA12N00 (size 18)
• Geometric displacement: 28 cm³/rev (size 28) / 18 cm³/rev (size 18)
• Nominal pressure: 280 bar
• Peak pressure: 350 bar
• Maximum speed (at Vg max): 3000 rpm (size 28) / 3300 rpm (size 18)
• Control type: DFR / DFR1 pressure and flow control (load-sensing type, X-T channel open or closed options)
• Direction of rotation: Clockwise (R, viewed from shaft end)
• Series: 31
• Housing material: High-strength cast iron
• Approximate weight: 15 kg (size 28) / 12 kg (size 18)
• Minimum inlet absolute pressure: 0.8 bar
• Maximum case pressure: approx. 2 bar

Key Technical Advantages

1. Swashplate axial-piston design combined with precision-machined valve plate and piston assemblies delivers high volumetric efficiency and stable flow output with low leakage even at the rated 280 bar.
2. Fast-responding DFR/DFR1 pressure-flow compound control precisely matches system demand, minimizing overflow losses and heat generation while improving overall energy efficiency.
3. High-strength cast-iron housing and optimized bearing arrangement provide excellent shock resistance and long service life under continuous industrial duty.
4. Full dimensional and interface interchangeability plus 100% simulated duty-cycle testing guarantees that mounting dimensions, port locations, shaft extension and control interfaces match original Rexroth A10VSO pumps exactly, enabling drop-in replacement without system re-commissioning.
5. Low-noise design and excellent suction characteristics support higher operating speeds, suitable for noise-sensitive factory environments.

Application Areas

Injection molding machines, die-casting machines, metal-forming equipment, industrial power units, machine-tool hydraulic systems, test benches, and auxiliary circuits on port machinery requiring stable medium-pressure variable flow in open-circuit configurations.

Expert Maintenance Tips

Verify shaft rotation matches system requirements (these models are clockwise R) before installation. Ensure adequate inlet supply with absolute pressure not lower than 0.8 bar to prevent cavitation. Use anti-wear hydraulic oil meeting ISO 4406 cleanliness standards (select viscosity according to operating temperature) and regularly check case drain pressure. On first start-up, run at low pressure and low speed to confirm absence of abnormal noise or leakage before gradually increasing pressure. Inspect shaft seals and control valve settings every 2000–3000 operating hours; replace seal kits as needed to maintain high volumetric efficiency.