Product Overview
The A10VS018DFR1/31R-PPA12K52 is a Bosch Rexroth A10VSO Series 31 swashplate-type axial piston variable displacement pump with a nominal displacement of 18 cm³/rev (1.10 in³/rev), rated operating pressure of 280 bar (28 MPa / 4060 psi), peak pressure capability of 350 bar (35 MPa / 5076 psi), maximum speed of 3000 rpm, output flow of approximately 27 L/min at 1500 rpm, maximum drive power of approximately 30 kW at 280 bar, and weight of approximately 12 kg. Designed for hydrostatic drives in open circuits, the pump features a swashplate-type axial piston rotary group, delivering output flow proportional to drive speed and displacement, with stepless variation via swashplate angle adjustment.
This model is equipped with DFR1 pressure-flow combined control (Pressure and Flow Controller), integrating pressure compensation and load sensing in a single controller. The DFR1 version has no connection between the X channel and the reservoir; unloading the LS pilot line must be accomplished through the valve system. This control method is particularly suitable for mobile hydraulic systems such as excavators and loaders requiring precise on-demand flow supply and constant pressure holding, delivering significant energy savings compared to fixed displacement pump systems.
The A10VSO Series 31 features low-noise operation, excellent suction performance, and long service life. The pump supports through-drive capability, enabling tandem connection with same-size A10VSO pumps or gear pumps for compact integration of multi-circuit hydraulic systems. The A10VS018DFR1/31R-PPA12K52 is widely deployed in excavators, loaders, cranes, and other construction machinery hydraulic systems.
Every A10VS018DFR1/31R-PPA12K52 undergoes 100% simulated duty-cycle testing prior to shipment — covering pressure holding, flow output, control response, and internal leakage — ensuring complete drop-in interchangeability with original Rexroth pumps without installation or plumbing modifications.
Technical Specifications
Model: A10VS018DFR1/31R-PPA12K52
Brand: Bosch Rexroth
Series: A10VSO Series 31
Pump Type: Open-circuit swashplate axial piston variable displacement pump
Nominal Displacement: 18 cm³/rev (1.10 in³/rev)
Rated Operating Pressure: 280 bar (28 MPa / 4060 psi)
Peak Pressure: 350 bar (35 MPa / 5076 psi)
Maximum Speed: 3000 rpm
Minimum Speed: 500 rpm
Output Flow at 1500 rpm: Approx. 27 L/min
Maximum Flow at 3000 rpm: Approx. 59 L/min
Maximum Drive Power at 280 bar: Approx. 30 kW
Drive Power at 1500 rpm, 280 bar: Approx. 12.6 kW
Control Type: DFR1 pressure-flow combined control (X-channel closed version)
Direction of Rotation: R (clockwise, viewed from shaft end)
Mounting Flange: ISO 3019-2 metric, 2-hole
Shaft Type: ISO keyed shaft
Seals: FKM (Fluoroelastomer)
Case Drain Ports: 2
Through-Drive Capability: Yes
Weight: Approx. 12 kg
Inlet Absolute Pressure Range: 0.8–30 bar
Case Drain Maximum Permissible Backpressure: ≤ 2 bar absolute (recommended < 1 bar)
Fluid Cleanliness Requirement: NAS Class 8 (ISO 18/16/13), system filter 10 μm
Recommended Fluid: ISO VG32 / VG46 anti-wear hydraulic oil (L-HM)
Operating Temperature Range: -20 to +80 ℃, optimal 40–55 ℃
A10VSO Series 31 Same-Family Displacement Reference (nominal conditions):
A10VSO10: 10 cm³/rev, 280 bar rated, 350 bar peak, max 3200 rpm
A10VSO18: 18 cm³/rev, 280 bar rated, 350 bar peak, max 3000 rpm, flow at 3000 rpm approx. 59 L/min, weight approx. 12 kg
A10VSO28: 28 cm³/rev, 280 bar rated, 350 bar peak, max 3000 rpm, flow at 3000 rpm approx. 84 L/min, weight approx. 15 kg
A10VSO45: 45 cm³/rev, 280 bar rated, 350 bar peak, max 2600 rpm, flow at 2600 rpm approx. 117 L/min, weight approx. 21 kg
A10VSO71: 71 cm³/rev, 280 bar rated, 350 bar peak, max 2200 rpm, flow at 2200 rpm approx. 156 L/min, weight approx. 33 kg
A10VSO100: 100 cm³/rev, 280 bar rated, 350 bar peak, max 2000 rpm, flow at 2000 rpm approx. 200 L/min, weight approx. 45 kg
A10VSO140: 140 cm³/rev, 280 bar rated, 350 bar peak, max 1800 rpm, flow at 1800 rpm approx. 252 L/min, weight approx. 60 kg
Data based on A10VSO Series 31 official technical specifications.
Key Technical Advantages
1. DFR1 Pressure-Flow Combined Control — Precise Power Management and Energy Savings
The A10VS018DFR1/31R-PPA12K52 features a DFR1 pressure-flow combined controller, integrating pressure compensation (DR) and load sensing (FR) functions in a single controller. This control method achieves coordinated constant pressure holding and on-demand flow supply through pressure feedback and flow demand coordination: when system pressure reaches the set point, the pump automatically reduces displacement to only leakage flow, eliminating relief losses; when system pressure drops, flow output is automatically restored. The DFR1 version has no connection between the X channel and the reservoir; unloading the LS pilot line must be accomplished through the valve system. The load sensing differential pressure is factory set at 20 bar (290 psi), adjustable from 10 to 22 bar. This control method is particularly suitable for mobile hydraulic systems such as excavators and loaders requiring precise flow and pressure coordination.
2. High Power Density and Compact Structure — 30 kW from 12 kg
The A10VSO18 delivers approximately 30 kW maximum power at 3000 rpm and 280 bar, weighing only approximately 12 kg, with power-to-weight ratio leading among comparable products. The swashplate axial piston design combined with an optimized rotary group achieves efficient power transmission within a compact structure. The pump’s mounting dimensions conform to ISO 3019-2 standards, enabling direct replacement with same-specification A10VSO pumps without modifying the mounting interface.
3. Low Noise Operation and Excellent Suction Performance
The A10VSO Series is renowned for low-noise operation, effectively suppressing pressure pulsation and fluid-borne noise through optimized valve plate flow passages and precision-machined rotary group. The pump delivers excellent suction performance with an inlet absolute pressure range of 0.8–30 bar, combined with optimized suction flow passages ensuring adequate suction even at maximum speed of 3000 rpm to prevent cavitation damage. The cradle bearing is hydrostatically unloaded, effectively distributing loads and reducing friction losses for improved operating efficiency and service life.
4. Through-Drive and Flexible System Integration
The A10VS018DFR1/31R-PPA12K52 supports through-drive capability, enabling tandem installation of same-size A10VSO axial piston pumps or gear pumps on the rear of the main pump for compact system configurations driven by a single prime mover. Through-drive capability provides 100% torque transmission, permitting installation of a second pump within permissible angular acceleration limits. This design provides exceptional integration flexibility in multi-circuit hydraulic systems, reducing the number of independent power units and lowering piping complexity and installation costs.
5. Exceptional Field Interchangeability and Media Compatibility
The A10VS018DFR1/31R-PPA12K52 features mounting flange (ISO 3019-2), shaft specifications (ISO keyed shaft), and port layouts conforming to Rexroth A10VSO Series 31 standards, enabling drop-in interchangeability with other A10VSO18 models of the same specification. The pump is compatible with mineral-based hydraulic oil and HF fire-resistant fluids, with FKM seals suitable for standard industrial hydraulic systems. For equipment currently using A10VSO18 series pumps, direct replacement installation is possible without modifying system installation interfaces or plumbing layouts.
Application Areas
Excavators: Small-to-medium excavator hydraulic systems, with DFR1 control delivering on-demand flow and precise speed control
Loaders: Wheel loader hydraulic working device and steering systems
Cranes: Truck crane and loader crane hydraulic swing and hoist systems
Construction Machinery: Concrete pump trucks and rotary drilling rigs auxiliary hydraulic circuits
Industrial Hydraulic Power Units: Machine tool clamping systems and small hydraulic press power sources, with low noise suited to indoor environments
Agricultural Machinery: Tractor hydraulic hitch and steering systems
Material Handling Equipment: Medium forklift and telehandler hydraulic power units
The A10VS018DFR1/31R-PPA12K52 is ideally suited for small-to-medium power hydraulic systems requiring 280 bar continuous working pressure and displacements in the 18 cm³/rev range — the classic configuration for excavator and loader hydraulic systems.
Expert Maintenance Tips
1. Shaft Alignment and Coupling Requirements
Maintain concentricity between the pump shaft and drive shaft within 0.05 mm. Flexible couplings are strongly recommended to accommodate minor angular misalignment. The A10VS018DFR1/31R-PPA12K52 features an ISO 3019-2 standard mounting flange and ISO keyed shaft — never strike the shaft end during installation to avoid damaging internal seals and bearings. Tighten mounting flange bolts in diagonal sequence to the specified torque. Couplings must be equipped with protective guards.
2. Pre-Start Filling and Venting Procedure (Mandatory)
Before initial startup, the pump housing must be filled with clean hydraulic oil and maintained full during operation. Slowly fill through the case drain port with ISO VG32 or VG46 anti-wear hydraulic oil to ensure adequate lubrication and sealing during startup. Operating an axial piston pump dry — even for a few seconds — will score the swashplate, valve plate, and piston slippers, causing immediate total pressure loss and irreversible damage. Start the pump in jog mode until the pump and piping are sufficiently filled and vented. After complete venting, run at low pressure for 5–10 minutes, then gradually increase to rated pressure.
3. DFR1 Controller Commissioning
Commission the DFR1 pressure-flow combined controller by separately setting the flow valve (FR) standby differential and the pressure valve (DR) cut-off pressure. The load sensing differential pressure (Δp) is factory set at 20 bar (290 psi), adjustable from 10 to 22 bar. The pressure compensation setting should be at least 10–15 bar below the system relief valve setting. Adjustment must be performed with the pump at full displacement and low operating pressure to avoid system pressure oscillation. The DFR1 version has a closed X channel; unloading the LS pilot line must be accomplished through the valve system.
4. Fluid Cleanliness and Filtration
The A10VS018DFR1/31R-PPA12K52 requires fluid cleanliness of NAS Class 8 (ISO 18/16/13). Use pressure line filters with 10 μm filtration accuracy. Avoid suction filters, which increase suction resistance and cavitation risk; if essential, use with a vacuum switch monitor. Install a breather filter with filtration accuracy ≤10 μm on the reservoir and regularly check oil level and fluid condition. Case drain backpressure must not exceed 2 bar absolute, with < 1 bar recommended.
5. Restart Procedure After Extended Shutdown
If the pump has been stored for more than 3 months, fill the interior with hydraulic oil, seal the ports, and store vertically before restarting. Manually rotate the shaft several turns to verify free rotation before restarting. Check for abnormal leakage at the case drain port. After startup, operate at low pressure for 10–15 minutes until oil temperature reaches normal operating range before applying full load. When using HF fire-resistant fluids, shorten oil change intervals and increase fluid sampling frequency due to reduced lubricity.
