421AK01088B ADU062 Vickers Piston Pump 62cc 280Bar

Product Overview

The 421AK01088B belongs to the Eaton Vickers 420 Series of open-circuit axial piston pumps, now supported under the Danfoss Power Solutions product portfolio. Featuring swashplate design with displacements from 41.0 cm³/rev to 80.0 cm³/rev, the series is engineered for medium-to-high pressure open-circuit hydraulic systems. The 420 Series is distinguished by its compact size, quiet operation, and flexible controller configurations, supporting pressure compensation, pressure-flow compensation (with LS load sense port), and torque limiting control options.

This model 421AK01088B corresponds to Danfoss model code ADU062R05AB10A2824000A2AB100CD08, with a displacement of 62.3 cm³/rev, SAE B 2-bolt mounting flange, 13-tooth 16/32 spline shaft, and SAE J518 Code 61 4-bolt split-flange main ports. This configuration is suitable for medium construction machinery, agricultural machinery, and material handling hydraulic main pump applications.

Manufactured to original Eaton Vickers 420 Series technical specifications with full drop-in interchangeability — no piping or mounting flange modifications required. Every pump undergoes 100% simulated load testing at the factory, covering pressure hold, flow response, and compensator dynamics.

Technical Specifications 

• Series: Eaton Vickers 420 Series / Danfoss ADU Series

• Design: Open-circuit axial piston variable pump, swashplate type

• Displacement: 62.3 cm³/rev (3.80 in³/rev)

• Rated Continuous Pressure: 280 bar (4060 psi)

• Maximum Intermittent Pressure: 320 bar (4600 psi)

• Peak Pressure: 350 bar (5000 psi)

• Rated Speed: 2,600 rpm (@1 bar absolute inlet)

• Maximum Speed: 2,800 rpm (standby)

• Minimum Speed: 600 rpm

• Control Type: Pressure-flow compensator with LS load sense port

• Pressure Compensator Setting Range: 207–214 bar (this configuration)

• Load Sense Differential Setting: 23–25 bar (this configuration)

• Mounting Flange: SAE B 2-bolt (SAE J744-101-2)

• Shaft Type: 13-tooth 16/32 spline (ANSI B92.1-1996)

• Main Port (Inlet): 2.00″ SAE J518 4-bolt split flange, Code 61

• Main Port (Outlet): 1.00″ SAE J518 4-bolt split flange, Code 61

• Rotation: Right-hand (clockwise)

• Weight: Approx. 22 kg (single seal) / 23 kg (dual seal)

• Housing Material: High-strength cast iron

• Maximum Theoretical Power: 75.6 kW (101.3 hp)

• Maximum Theoretical Torque: 278 N·m (205 lb-ft)

• Bearing Life @140 bar: 33,500 hours (B10)

• Fluid Cleanliness: ISO 4406 18/16/13 or better

Model Code Interpretation (ADU062R05AB10A2824000A2AB100CD08):

• ADU062: 420 Series variable piston pump, 62.3 cm³/rev displacement

• R: Right-hand (clockwise) rotation, viewed from shaft end

• 05: SAE B 2-bolt mounting flange, SAE B 7/8″ 13T spline shaft

• AB: Side ported, inlet 2″ SAE 4-bolt Code 61, outlet 1″ SAE 4-bolt Code 61

• 1: Drain port 7/8″-14UNF-2B SAE O-ring, top

• 0: No diagnostic port

• A: Load sensing & pressure compensator control

• 28: Pressure compensator setting 207–214 bar

• 24: Load sense differential setting 23–25 bar

• 00: No secondary pressure setting

• A: Load sense bleed down orifice

• 1: Standard displacement stop

• AB100: Design number and hardware feature code

• CD08: Customization suffix

Data based on Eaton 420 Series official technical manual (E-PUPI-TM002-E5) and Danfoss PowerSource product database.

Key Technical Advantages

1. Compact Design — Space-Saving Installation

The 420 Series features a one-piece housing design with approximately 25% fewer components than traditional pumps, fundamentally reducing leak points and simplifying maintenance. The ADU062 specification weighs only approximately 22 kg, offering outstanding power density in the 62 cc displacement class for easy installation in space-constrained mobile hydraulic equipment.

2. Pressure-Flow Compensation Control — On-Demand Flow with Fast Response

The 420 Series features standard pressure-flow compensator with LS load sense port, continuously adjusting swashplate angle based on load pressure and pressure differential across the metering orifice to precisely match pump output to actuator demand. The series delivers the fastest response and recovery times in the open-circuit piston segment, maintaining low standby pressure of approximately 150 psi (~10 bar) with exceptional stability, significantly reducing heat generation and energy waste. During standby or light-load conditions, pump displacement automatically reduces to the minimum flow required for leakage compensation, fundamentally eliminating relief losses.

3. Quiet Operation and High Reliability

The 420 Series employs pressure-lubricated saddle type swashplate design for longer life and compact installation. Optimized flow passage design and housing acoustic structure deliver significantly lower operating noise than comparable products. Bearing B10 design life at 140 bar is 33,500 hours, with long service life maintained even at 210 bar. High-strength cast iron housing and precision-machined piston pairs ensure stable volumetric efficiency at 280 bar continuous pressure.

4. Flexible Controller Configurations and Mounting Options

The 420 Series offers multiple control options including pressure compensation, pressure-flow compensation (with or without LS port), and torque limiting, allowing users to select configurations based on system requirements. Mounting flanges are available in SAE B 2-bolt and SAE C 2/4-bolt options, with shaft ends in keyed or splined designs, and port locations in side or rear configurations to meet different host platform interface requirements. The full series supports thru-drive options for tandem pump configurations.

Application Areas

• Construction Machinery: Medium excavator hydraulic main pump, wheel loader work equipment hydraulics, backhoe loader hydraulic drive

• Agricultural Machinery: Tractor hydraulic hitch and steering systems, combine harvester hydraulic drive, sprayer hydraulic systems

• Material Handling: Forklift hydraulic lift and tilt circuits, telehandler hydraulic drive

• Municipal & Road Machinery: Street sweeper hydraulics, refuse truck hydraulic drive, asphalt paver hydraulic power

• Industrial Hydraulic Power Units: Hydraulic power unit main pumps, pressure test bench hydraulic sources

• Specialty Vehicles: Aerial work platform hydraulic systems, municipal engineering vehicle hydraulic drive

Expert Maintenance Tips

Pre-Installation Cleanliness Control: Before installing 420 Series pumps, 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 case with clean hydraulic oil to the maximum allowable level. Dry-start is strictly prohibited. Ensure concentricity between the pump shaft and prime mover shaft is maintained within 0.05 mm, and use a flexible coupling to avoid additional radial loads.

Pressure-Flow Compensator Calibration: This model 421AK01088B has a pressure compensator setting of 207–214 bar and a load sense differential setting of 23–25 bar. Monitor LS port and outlet pressures with a gauge of at least 1.6 accuracy class during adjustment. Turn the adjustment screw clockwise to increase the setting, counterclockwise to decrease. Adjustment increments should not exceed half a turn per step. The LS signal line must be leak-free and not cross-connected to other circuits.

Operating Oil Temperature Management: The 420 Series recommended operating oil temperature range is 15–80°C. When starting with oil temperature below 15°C, warm the hydraulic oil or run at low speed and no load until oil temperature reaches 15°C before applying load. Recommended viscosity grade: VG 32–46 mineral hydraulic oil, optimum working viscosity 16–40 cSt. Prolonged operation above 80°C accelerates seal aging and fluid degradation.

Oil Maintenance Schedule: Replace hydraulic oil and filter after the first 500 hours of operation. Thereafter, replace every 2,000 hours or 12 months, whichever comes first. 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. Pressure-compensated pumps are sensitive to fluid contamination — contaminant particles can jam the compensator spool, causing setpoint drift. Maintain return filter efficiency at 10 μm or finer.

Long-Term Storage Protection: For pumps stored over 3 months, drain case 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. Always refill the case to the maximum allowable level before restart.