Rexroth A2FO107 Fixed Piston Pump Replacement | 9423259

Genlu Hydraulic excels as a world-class engineered fluid power component manufacturer, open-circuit high-pressure hydraulic infrastructure expert, and strategic B2B global supplier of heavy-duty rotary fluid power machinery. The A2FO107 Series High-Pressure Bent-Axis Axial Piston Fixed Displacement Pump Platform (encompassing the clockwise A2FO107/61R and counter-clockwise A2FO107/61L variations, and emphasizing critical OEM high-frequency cross-reference parts codes A2FO107/61R-PAB05 / 9423259 and A2FO107/61R-PBB05 / 9438282) is custom-engineered and manufactured as a premium, structurally reinforced, and 100% drop-in interchangeable high-tier replacement for the definitive global industry benchmark—the Bosch Rexroth Series 61 bent-axis fixed pumps. This platform is widely deployed as the primary hydraulic power generator across global vocational heavy-duty truck tipping gears, refuse compactor stations, truck-mounted knuckle-boom cranes, and concrete transit mixer auxiliary functions.

Operating as the primary flow-and-pressure-generating core within open hydraulic loops, bent-axis piston pumps handle severe continuous high-pressure conditions (nominal 350 bar to 400 bar, with intermittent shock peaks up to 450 bar) while offering high fluid self-suction capabilities and contaminant resistance compared to swashplate designs. Genlu’s Rexroth-style replacement pumps mirror the exact geometric profiles, machining tolerances, and fluid dynamics specified in the original factory technical manuals. We guarantee absolute drop-in compatibility across the standard SAE 4-bolt mounting flange (125.0 mm pilot diameter), straight cylindrical keyed or splined drive shaft configurations (P-shaft or Z-shaft options), rear-mounted high-pressure port connections (A05 or B05 manifold configurations), and the core 40-degree bent-axis spherical valve plate rotating cylinder assembly. Prior to final warehouse dispatch release, every single pump assembly undergoes 100% Full-Simulation Condition Testing on multi-channel digitized test stands to verify peak volumetric efficiency, nominal delivery linearity, and low acoustic emissions under maximum loading.

Technical Specifications 

• Product Design Series: A2FO Series, Design Index 61 High-Pressure Fixed Displacement Bent-Axis Axial Piston Pump

• Nominal Frame Size & Displacement Matrix: Size 107, delivering precisely 106.7 $cc/rev$ nominal geometric displacement volume

• Core Covered Specific OEM Cross-Code Mapping:

  • 9423259 / A2FO107/61R-PAB05 Configuration (Series 61, Right-hand rotation, parallel keyed shaft, NBR elastomer seal package, B05 standard rear-mounted SAE split-flange port configuration)

  • 9438282 / A2FO107/61R-PBB05 Configuration (Series 61, Right-hand rotation, parallel keyed shaft, premium high-temperature Fluorocarbon (FKM/Viton) seal package, B05 standard rear-mounted SAE split-flange port configuration)

• Continuous Rated Operating Pressure Boundary: 350 bar to 400 bar (35 MPa – 40 MPa) continuous duty loading envelope

• Maximum Intermittent Peak Pressure Threshold: Rated up to 450 bar (45 MPa / 6525 psi) for transient shock protection

• Maximum Permissible Continuous Rotational Velocity Limit:

  • Rated up to 2150 RPM under unpressurized open-circuit self-suction conditions

  • Extendable up to 3000 RPM when backed by a pressurized system inlet charge

• Maximum Theoretical Continuous Volumetric Output Flow: Up to 229 L/min when operating at a self-suction speed of 2150 RPM

• Primary Structural Metallurgy: Heavy-walled monolithic ductile iron housing matched with tapered 9-piston forged alloy steel connecting rod-shaft modules

• Control Type: Fixed Displacement (Constant volumetric output relative to input drive shaft speed)

• Total Pump Assembly Dry Mass: Approximately 42.0 kg (Utilizing a compact, slim-profile body geometry to support tight retrofitting environments)

Key Technical Advantages:

• Advanced 40-Degree Bent-Axis Spherical Valve Plate Design for High Volumetric Efficiency: The A2FO107 features a fixed 40-degree angle between the cylinder barrel axis and the drive shaft line. The conical piston rods are directly hinged to the drive shaft flange. This architecture eliminates side forces on the pistons within the cylinder bores, minimizing mechanical friction. Paired with a precision-ground spherical valve plate, this setup maintains a volumetric efficiency above 97% under continuous 400 bar loading.

• Excellent Self-Suction Capabilities for Open-Circuit Operation: The fluid entry pathways into the cylinder barrel are short and straight, minimizing internal fluid friction and flow restrictions. This bent-axis design supports a self-suction velocity up to 2150 RPM, helping protect the system from vacuum starvation and cavitation erosion during cold-weather startups with high-viscosity oil or when operating at high altitudes.

• Monolithic Forged Shaft Flange Supported by Heavy-Duty Tapered Roller Bearings: The drive shaft is forged from high-grade alloy steel (e.g., 42CrMo) and supported by large twin tapered roller bearings. This configuration accommodates high radial and axial overhung loads, making it suitable for absorbing side forces generated by direct gear engagement with truck Power Take-Off (PTO) units, which helps prevent shaft fatigue and premature bearing wear.

• High Particle Contaminant Resistance for Reliable Service Life: Because the pistons are guided by internal wear rings and joint rods rather than the flat sliding shoes used in swashplate pumps, the assembly is less sensitive to fine particulate matter. Combined with a case-hardened (HRC62) spherical distribution plate, this design minimizes abrasive wear and reduces full-lifecycle breakdown rates compared to standard open-circuit pumps.

Application Areas:

• Heavy Vocational Trucks, Mobile Transport Upper Structures & Refuse Systems: Heavy-duty mining dump truck hoist cylinders, high-capacity truck-mounted knuckle-boom cranes, and main compaction cylinders for municipal waste transport vehicles.

• Construction Infrastructure, Mobile Carriers & Foundation Equipment: Continuous agitation circuits for concrete boom pump hoppers, auxiliary material feed drives for cold-milling road machines, and primary fluid supply for heavy-duty airport transport attachments.

• Industrial High-Pressure Hydraulic Presses & Centralized Power Units: High-tonnage scrap metal baling machinery, brick-molding structural presses, and heavy-duty forging unit power circuits.

Expert Maintenance Tips:

• Mandatory Casing Priming and Manual Rotation Prior to Initial Power-Up: The large tapered roller bearings and spherical rod joints within the A2FO107 depend on case fluid immersion for lubrication. Before initial commissioning, installation after overhaul, or restarting after long shutdowns, fill the pump housing with at least 3.0 liters of clean hydraulic oil through the highest case port and manually rotate the shaft 5 turns. Running dry will score the connecting rod joints during the first few seconds of operation.

• Verify Rotational Direction Compatibility and Case Drain Back-Pressure: This pump series strictly separates R (Clockwise) and L (Counter-Clockwise) structural configurations. Confirm the actual rotation direction of your vehicle’s PTO drive shaft before installation; running the pump in reverse will cause immediate damage. Additionally, ensure the case drain line is unrestricted and maintains continuous back-pressure below 2 bar to protect the front shaft lip seal.

• Align Component Tolerances During Direct-Coupled Truck PTO Installation: When face-mounting the A2FO107 directly onto a standard gearbox PTO pad, use a dial indicator to check the concentricity and perpendicular alignment between the PTO internal spline and the pump shaft, keeping variance within 0.05 mm. Misalignment subjects the drive shaft and bearings to excessive cyclic bending stress, leading to premature fatigue cracks or shaft fracturing under load.