Product Overview
The A10VO45 and A10VO60 are Bosch Rexroth A10VO Series 52 open-circuit axial piston variable displacement pumps featuring swashplate design for medium-pressure hydraulic systems. The A10VO60DFR1/52R-VSD61N00 (Material # R902549877) is manufactured by Bosch Rexroth as an OEM unit, while the A10VO45DFR1/52L-PSC12K68-SO702 and A10VO45DFR1/52L-VRC12K04-SO804 are interchangeable replacements manufactured to original technical specifications with full drop-in interchangeability — no piping or mounting flange modifications required. Each pump undergoes 100% simulated load testing at the factory, covering pressure hold, flow response, and DFR1 control valve dynamic characteristics, ensuring seamless replacement in excavator main pump and industrial hydraulic power unit applications.
Technical Specifications
Series: Bosch Rexroth A10VO Series 52
Design: Swashplate axial piston variable pump, open circuit
Displacement: 45 cc/rev (A10VO45) / 60 cc/rev (A10VO60)
Nominal Pressure: 280 bar (continuous)
Peak Pressure: 350 bar (intermittent)
Minimum Speed: 600 rpm
Maximum Speed: 3000 rpm (A10VO45) / 2700 rpm (A10VO60)
Control Type: DFR1 pressure and flow controller (X-port plugged, with flushing function)
Control Differential Pressure Δp: Standard 14 bar, adjustable 14–22 bar
Pilot Oil Consumption: Max. approx. 3 L/min (DFR1)
Mounting Flange: ISO SAE standard 2-hole pattern
Working Ports: Port B and Port S, SAE flange
Seal Material: FKM (fluororubber)
Direction of Rotation: Clockwise when viewed from shaft end (R-type)
Weight: Approx. 21–23 kg (A10VO45) / 30 kg (A10VO60)
Data based on Bosch Rexroth A10VO Series 52 technical documentation.
Key Technical Advantages
1. DFR1 Pressure and Flow Compound Control
The DFR1 control combines a pressure compensator (DR) and a flow controller (FR) in one integrated unit. The pressure compensator limits maximum system pressure to the setpoint (typically 280 bar from factory), while the flow controller continuously adjusts the swashplate angle based on the pressure differential across the metering orifice (Δp = 14 bar), precisely matching pump output to actuator demand. When the system is in standby with the X-port plugged, the pump delivers only minimal flushing flow, with standby pressure approximately 1–2 bar above the differential pressure setting. This mechanism eliminates relief losses entirely, reducing energy consumption by over 20% in excavator multi-valve combined operation. Note: DFR1 does not include unloading from port X to the reservoir — the LS circuit must be unloaded externally; otherwise, the DRSC control valve should be specified.
2. Swashplate Variable Mechanism with Fast Response
The A10VO series utilizes swashplate-type axial piston variable design, with flow proportional to drive speed and displacement. The swashplate angle is infinitely adjustable for stepless flow control. The DFR1 control valve features short control response times, enabling quick response to command changes for precise flow matching in load-sensing systems — critical in mobile machinery requiring frequent start-stop and speed changes.
3. High Power Density and Compact Construction
The A10VO series features a cast iron housing that delivers high power output within a compact envelope. The A10VO45 achieves 280 bar nominal pressure at 45 cc/rev displacement, with power density leading the class. Standard SAE mounting flange and splined shaft design ensure full compatibility with original system installations.
4. Low-Noise Operation and Long Service Life
Inlet and outlet flow passages are optimized, combined with housing acoustic optimization, delivering significantly lower operating noise than comparable products. FKM fluoroelastomer seals are standard across the range, compatible with mineral and synthetic hydraulic fluids. The swashplate axial piston group is manufactured from high-strength alloy steel with precision-honed cylinder bores, maintaining high volumetric efficiency and extended service life at 280 bar continuous pressure.
Application Areas
Construction Machinery: Excavator main pump (arm/swing/travel circuits), loader work equipment, bulldozer hydraulic drive
Material Handling: Forklift hydraulic lift and tilt systems
Agricultural Machinery: Tractor hydraulic hitch and steering systems, combine harvester hydraulic drive
Industrial Hydraulic Power Units: Injection molding machine hydraulic power unit, hydraulic press main drive
Specialty Vehicles: Port machinery hydraulic drives, municipal vehicle upper-body hydraulics
Expert Maintenance Tips
Pre-Installation Inspection: Before installing the A10VO45/A10VO60, verify hydraulic system cleanliness meets ISO 4406 18/16/13 or better. Port plugs should be removed and piping connected immediately after unboxing — environmental exposure should not exceed 15 minutes. Before first start, fill the pump housing with clean hydraulic oil until oil overflows from the drain port. Dry-start is strictly prohibited. Ensure the concentricity between the prime mover drive shaft and the pump shaft is maintained within 0.05 mm.
DFR1 Control Valve Calibration: The DFR1 control valve has a factory standard differential pressure setting of 14 bar. If a different setting is required after installation, it can be adjusted within the 14–22 bar range. Monitor LS port (X port) pressure with a gauge during adjustment. Turn the adjustment screw counterclockwise to decrease the setting, clockwise to increase. Adjustment increments should not exceed half a turn per step. Since the DFR1 control valve has no unloading function from port X to the reservoir, verify that the LS circuit in the system can fully unload during standby; otherwise, switch to the DRSC control valve.
Oil Maintenance Schedule: Replace hydraulic oil and filter after the first 500 hours of operation. Thereafter, replace every 2000 hours or 12 months, whichever comes first. Recommended viscosity grade: VG 46 mineral hydraulic oil, operating temperature range 4°C to 85°C. If the system is equipped with an online particle counter, replace oil and inspect filter differential pressure immediately when cleanliness drops to ISO 4406 20/18/15.
Long-Term Storage Protection: For pumps stored over 3 months, drain housing oil, fill with rust-preventive oil, and plug all ports. Before recommissioning, flush with flushing oil for 30 minutes and confirm flushing oil cleanliness meets specification before connecting to the system.
