Product Overview
The R902481103 corresponds to the A10VSO71DRG/31R-VSA42K01—a Bosch Rexroth A10VSO series 31 swashplate-type axial piston variable displacement pump designed for open-circuit operation with DRG remote pressure control. With a displacement of 71 cc/rev, a nominal pressure rating of 280 bar, and a maximum pressure of 350 bar, this pump serves as a workhorse in medium-pressure mobile and industrial hydraulic systems.
The A10VSO71DFR1/31R-PPA12N00 variant features pressure-flow compound control (DFR1), sharing the same 280 bar nominal pressure rating and operating at speeds from 1500 to 2200 rpm. Both models utilize an ISO 3019-1 (SAE) 2-hole mounting flange, keyed or splined drive shaft, and SAE flange ports, ensuring direct compatibility with mainstream equipment worldwide.
Every pump undergoes 100% simulated operating-condition testing before shipment, including rated pressure hold, flow characteristic verification, and control response validation—delivering immediate reliability upon installation.
Technical Specifications
Model Identification:
R902481103 — A10VSO71DRG/31R-VSA42K01: DRG remote pressure control, clockwise rotation (R), FKM seals (V), SAE splined shaft (S), SAE 2-hole flange (A), SAE flange ports/metric threads (42), no through-drive (K01)
A10VSO71DFR1/31R-PPA12N00: DFR1 pressure-flow control, clockwise rotation (R), NBR seals (P), keyed shaft (P), SAE 2-hole flange (A), SAE flange ports/metric threads (12), no through-drive (N00)
Displacement:
Pressure Ratings:
Speed Range:
Theoretical Flow:
Control Types:
DRG Remote Pressure Control — Enables remote setting of maximum pump pressure via an external pilot relief valve at port X; standard control spool differential pressure setting: 20 bar
DFR1 Pressure-Flow Control — Combines pressure compensation with load-sensing flow regulation; X-T port closed with no flushing function
Structural Parameters:
Pump type: Open-circuit swashplate axial piston variable displacement
Mounting flange: ISO 3019-1 (SAE) 2-hole
Drive shaft: SAE splined (type S) or keyed (type P)
Rotation: Clockwise (R), viewed from shaft end
Port connections: SAE flange per ISO 6162
Weight: Approximately 33–35 kg (configuration-dependent)
Key Technical Advantages
1. Complete Model Code for Precise Interchange
The A10VSO series 31 model code system spans 13 encoding positions covering displacement, control type, series designation, rotation direction, seal material, drive shaft, mounting flange, port configuration, and through-drive options. Users can match the exact model code from the equipment nameplate (e.g., A10VSO71DRG/31R-VSA42K01 or A10VSO71DFR1/31R-PPA12N00) to avoid installation incompatibility caused by control type or interface mismatches.
2. DRG Remote Pressure Control for Multi-Condition Adaptability
The DRG control enables remote setting of maximum pump pressure via an external pilot relief valve connected to port X—no pump replacement required for pressure level changes. The standard control spool differential pressure is set at 20 bar, delivering responsive performance suitable for multi-stage pressure switching or remotely operated heavy mobile equipment.
3. DFR1 Pressure-Flow Compound Control Optimizes System Efficiency
DFR1 integrates pressure compensation with load-sensing flow regulation. When actuators stop, the pump automatically reduces displacement to near zero, maintaining only the minimum pressure required for control—significantly reducing system heat generation and energy loss. The closed X-T port design eliminates flushing circuit leakage, making it ideal for industrial hydraulic systems requiring high flow control precision.
4. Compact Architecture with High Power Density
The A10VSO71 delivers a maximum flow of 156 L/min at 71 cc/rev displacement with a pump weight of approximately 33–35 kg, achieving a favorable power-to-weight ratio. The swashplate variable displacement mechanism enables a compact control package that fits within most equipment engine compartments and installation envelopes.
5. SAE Standard Interfaces Reduce Replacement Cost
The combination of ISO 3019-1 (SAE) 2-hole flange, SAE flange ports, and standard splined/keyed drive shaft enables direct drop-in replacement of original Rexroth pumps and other brand pumps with identical mounting interfaces—no adapter plates or piping modifications required.
Application Areas
Machine tool hydraulic systems (injection molding machines, presses, bending machines)
Metallurgical equipment hydraulic power units
Forging machinery and mining equipment hydraulic transmission systems
Crane and construction machinery hydraulic systems
High-power hydraulic transmission systems and industrial hydraulic power units
Marine deck machinery hydraulic drive systems
Expert Maintenance Tips
1. Pre-Installation Model Verification
Verify the complete model code on the pump nameplate before installation. Pay particular attention to control type (DRG or DFR1), rotation direction (R or L), drive shaft type, and mounting flange specification. For DRG models, confirm that the pilot line to port X is correctly connected to the external pilot relief valve.
2. Hydraulic Fluid Cleanliness Control
A10VSO series piston pumps demand high fluid cleanliness. Recommended cleanliness level: no lower than ISO 4406 18/16/13 (equivalent to NAS 1638 Class 8). Suction filter rating should be no coarser than 10 μm; pressure line filter rating no coarser than 10 μm.
3. Case Drain Line Requirements
The case drain line must remain unobstructed, with back pressure not exceeding 0.5 bar absolute. The drain line end should always remain submerged below the oil level in the reservoir to prevent air ingestion. Case drain ports (L and L1) must not be interchanged.
4. DRG Control Commissioning
When commissioning DRG control, set the external pilot relief valve to minimum pressure first. Start the pump, then gradually increase pilot pressure while observing system pressure response. The standard control spool differential pressure is 20 bar. For higher system pressure precision, a precision pressure reducing valve may be installed at port X for secondary regulation.
5. First Start-Up Procedure
Fill the pump housing with clean hydraulic oil before first start. Run at 600–800 rpm unloaded for 5–10 minutes to purge air. Confirm no suction line leakage and steady oil flow from the case drain line before gradually increasing speed and loading to rated conditions. In low-temperature environments, use anti-wear hydraulic oil with a viscosity index of no less than 140 and pre-heat the system before startup.
