Rexroth A10VG28HW1 & A10VG45DA1D2 Variable Piston Pump

Genlu Hydraulic excels as an elite-tier global developer and precision manufacturer of high-pressure closed-circuit axial piston pumps, high-performance hydraulic motors, and industrial-grade proportional valves for global B2B industrial application networks. The A10VG Series High-Pressure Variable Axial Piston Pump—engineered to deliver a premium 100% drop-in interchangeable alternative to Germany’s definitive closed-loop standard, specifically targeting the highly sophisticated Bosch Rexroth model codes A10VG28HW1/10L-NSC10F013S-S and A10VG45DA1D2/10R-NSC10F025SH-S (and comprehensively encompassing the entire A10VG18, A10VG28, and A10VG45 platform configurations)—represents a premium fluid-power solution optimized for hydrostatic closed-circuit transmission networks. This high-density assembly integrates a variable swashplate main pump, a high-efficiency auxiliary internal gear charge pump, and a complete closed-loop protection block (consisting of dual-stage high-pressure cross-relief valves and charge check overrides). It stands globally as the definitive primary drive component for mini/medium excavator crawler drivetrains, agricultural harvester traction drives, and heavy-duty industrial closed-loop winches.

In continuous heavy-duty hydrostatic operations, closed-circuit oil media circulates directly between the pump and motor without transitioning through an open reservoir, requiring the pump to withstand rapid, full-stroke forward/reverse displacement scaling at a continuous 30.0 MPa. Furthermore, the unit must regularly survive transient hydraulic pressure spikes caused by sudden directional reversals. Substandard aftermarket alternative pumps lacking exact metallurgical bimetallic cylinder coatings or suffering from poor charge-pump volumetric delivery face catastrophic failures under high loads, typically manifesting as sharp charge pressure drops when hot, expanded internal cross-slippage, sluggish directional control, and eventual total stall. Genlu’s premium A10VG28 and A10VG45 replacement pumps are reverse-engineered to perfectly replicate the hydrostatic fluid film force balancing, advanced bimetallic sintering matrices, and modular HW (hydraulic servo-mechanical) or DA (speed-related) control valve logic detailed in official Bosch Rexroth engineering documentation. Whether validating the standard SAE mounting flange profiles, the high-torque thru-drive auxiliary shaft outputs, or the pilot control block bolt patterns, our pumps guarantee 100% mechanical and functional drop-in interchangeability. Prior to delivery, each unit undergoes 100% Full-Simulation Condition Testing on automated test configurations to verify full-stroke variable timing, charge pump delivery tracking, and control valve hysteresis loop boundaries, ensuring seamless integration directly upon installation.

Technical Specifications 

• Product Pump Classification: A10VG Series Variable Axial Piston Pump for Closed-Circuit Hydrostatic Drives

• Specific Core Configuration Code One: A10VG28HW1/10L-NSC10F013S-S (Hydraulic Servo Mechanical Control, 10 Series, Counter-Clockwise Left Hand Rotation)

• Specific Core Configuration Code Two: A10VG45DA1D2/10R-NSC10F025SH-S (Speed-Related DA Control, 10 Series, Clockwise Right Hand Rotation)

• Series Platform Coverage Horizon: Full mechanical interchangeability for A10VG18, A10VG28, and A10VG45 frame lines

• Nominal Geometric Displacement: 28.0 $cc/rev$ (for A10VG28) / 45.0 $cc/rev$ (for A10VG45)

• Maximum Continuous Operating Pressure: 30.0 MPa (300 bar / 4350 PSI)

• Maximum Intermittent Peak Pressure Threshold: Up to 35.0 MPa (350 bar / 5075 PSI) during transient system peaks

• Integrated Charge Pump Displacement capacity: 5.3 $cc/rev$ (28 frame) / 8.4 $cc/rev$ (45 frame)

• Maximum Permissible Operational Input Speed: 3600 RPM (A10VG28) / 3300 RPM (A10VG45) at max displacement

• Control Mechanism Profile (HW): HW1 — Hydraulic servo control via mechanical linkage steering for smooth manual-override scaling

• Control Mechanism Profile (DA): DA1D2 — Speed-related pilot control, modulating pilot pressure in proportion to drive shaft RPM, with hydraulic directional valves

• Drive Shaft Output Spline Geometry: S — Standard ANSI B92.1a standard flat root side fit splined shaft arrangement

• Thru-Drive Auxiliary Interface Profile: F013 / F025 — Universal thru-shaft setup equipped with an internal splined coupling to permit rear-series installation of a secondary pump

• Total Pump Assembly Net Dry Weight: A10VG28 approx. 29.0 kg / A10VG45 approx. 39.0 kg (High-rigidity industrial iron casing)

Key Technical Advantages:

• 100% Integrated Multifunctional Closed-Circuit Block Valves: The rear section of the pump incorporates two high-pressure cross-over relief valves with integrated charge-check functions and a dedicated charge pressure limiting valve. This high-density configuration responds within 5 milliseconds during system shocks, redirecting spike media to the low-pressure side or reservoir to protect the piston group while preserving dynamic thermal balance.

• Advanced Tri-Element Bimetallic Sintered Cylinder and Precision Piston Groups: The cylinder-to-valve plate interface utilizes a high-density, tri-element copper alloy layer paired with induction-hardened, spherically matched piston shoes. This construction sustains a resilient fluid-static lubrication film at a continuous 30.0 MPa, keeping volumetric efficiency above 96% even during sustained operation in 75°C environments.

• Modular HW / DA Precision Pilot Control Valve Manifolds: The HW mechanism uses zero-backlash linkage rods to deliver a control hysteresis under 1.5%, enabling operators to modulate flow via minor lever inputs. The DA control block features speed-sensing orifices and an internal pilot spool to automatically match output flow with prime mover RPM, preventing engine stall conditions.

• Rigid Cast Iron Casing with CFD-Optimized Flow Paths and Thru-Drive Support: Cast from high-elasticity nodular iron, the pump casing features internal oil channels optimized through Computational Fluid Dynamics (CFD). The smooth, large-radius channel cross-sections minimize flow restriction and aeration noise during circuit reversals, lowering noise output by 3-5 dB(A) compared to alternative components, while the thru-drive provides total structural torque transfer.

Application Areas:

• Hydrostatic Traction Drives for Engineering Machinery: Main power unit for crawler excavator travel networks and high-output skid steer loaders.

• Modern Agricultural Machinery & Combined Harvester Traction Drivetrains: Hydrostatic Static Transmission (HST) variable pump for grain, corn, and wheeled harvesting machinery.

• Industrial Closed-Loop Drives and Heavy-Duty Marine Winches: High-pressure power supply for marine crane winches, anchor windlasses, and industrial cable-pulling platforms.

Expert Maintenance Tips:

• Mandatory Pre-Commissioning Case Priming Rule for Closed Circuits: The internal piston shoes and swashplate assemblies in A10VG pumps cannot pull oil via self-priming at initial startup. Before running the pump for the first time, or after complete fluid flushes, you must pre-fill the pump body through the uppermost case drain port (T1 or T2) with at least 1.5L (A10VG28) or 2.5L (A10VG45) of clean fluid. Running the pump dry will destroy the rotating kit within seconds.

• Continuous Charge Pressure Monitoring Protocols During Tuning: The ability to scale pump displacement and maintain circuit cooling depends on adequate charge pressure. Always attach a 6.0 MPa pressure gauge to the charge test port (Port G) during commissioning. At minimum engine idle, charge pressure must measure between 1.8 and 2.2 MPa (18–22 bar). If pressure drops below 1.5 MPa, stop operation immediately to check the suction filters or charge pump to prevent component starvation.

• Strict Fluid Cleanliness Maintenance and Filtration Maintenance Thresholds: Hydrostatic closed loops are highly sensitive to particle buildup due to continuous oil re-circulation. The fluid media must be maintained at a cleanliness level of NAS Grade 6 (ISO 17/14) or better. Use dedicated closed-circuit filtration elements with a rating of 10 microns or finer and an electrical clogging indicator, and replace the initial filter after the first 50 hours of operation.