90R075KC2NN60L4S1D03GBA232320 Sauer Danfoss Pump 42MPa

Product Overview

The 90R075KC2NN60L4S1D03GBA232320 is a Sauer Danfoss Series 90 swashplate-type axial piston variable displacement pump with a nominal displacement of 75 cm³/rev, purpose-designed for hydrostatic transmission systems in closed circuits. The Series 90 design utilizes a parallel axial piston/slipper concept in conjunction with a tiltable swashplate to vary the pump’s displacement, enabling stepless displacement adjustment through swashplate angle variation. The pump features an integrated charge pump supplying boost flow, loop cooling, and control pressure to the closed-circuit system, with smooth flow direction change as the swashplate passes through neutral.

The full order code 90R075KC2NN60L4S1D03GBA232320 follows the Sauer Danfoss Series 90 standard coding system. The code decodes as follows: 90R indicates Series 90 closed-circuit variable pump, R for right-hand rotation (clockwise, viewed from shaft end); 075 is the nominal size (75 cm³/rev displacement); KC specifies Electro-hydraulic Displacement Control (EDC) with MS connector (KA variant of the KA/KP EDC control options); 2 is the control variant code; NN indicates no auxiliary mounting pad; 60 is the charge pump displacement code; L4 is the filtration code; S1 is the shaft configuration code; D03 is the control orifice diameter code; GBA indicates special hardware features (valve plate configuration); 232320 specifies pressure settings and configuration parameters.

Manufactured to exact Sauer Danfoss 90R075 platform specifications, this pump delivers true drop-in interchangeability — identical mounting flange (SAE-C 4-bolt, per ISO 3019-1), shaft specification, port positions, and displacement rating. Every unit undergoes 100% simulated operating condition testing before shipment.

Technical Specifications 

The following specifications are based on Sauer Danfoss Series 90 official technical data and publicly available product data. Configuration-specific parameters should be confirmed against original factory calibration data.

• Model: 90R075KC2NN60L4S1D03GBA232320

• Manufacturer: Sauer Danfoss

• Series: Series 90

• Design: Swashplate-type axial piston variable displacement pump, closed-circuit

• Nominal Size: 075

• Geometric Displacement: 75 cm³/rev (4.57 in³/rev)

• Rated Working Pressure: 420 bar (42 MPa / 6090 PSI)

• Peak Pressure: 480 bar (6960 PSI)

• Rated Speed: 3600 rpm

• Maximum Speed: 3950 rpm

• Minimum Speed: 500 rpm

• Rotation Direction: Right hand (clockwise, viewed from shaft end)

• Control Type: KC — Electro-hydraulic Displacement Control (EDC), MS connector, 14–85 mA control current (reference: same-series KA/KP control parameters)

• Integrated Charge Pump Displacement: Approx. 17 cc/rev (60 code configuration)

• Mounting Flange: SAE-C 4-bolt flange (ISO 3019-1)

• Weight (with MA Control): Approx. 49 kg (108 lb)

• Theoretical Flow at Rated Speed: 270 L/min

• Torque at Maximum Displacement (Theoretical): 1.19 N·m/bar (730 lbf·in/1000 psi)

• Rotary Group Moment of Inertia: 0.0096 kg·m²

• Operating Fluid: Mineral hydraulic oil (ISO VG 46 / VG 68)

• System Type: Closed-circuit hydraulic system

Key Technical Advantages

1. Precise Variable Control via Electro-hydraulic Displacement Control (EDC)

The pump employs KC electro-hydraulic displacement control, in which an electro-hydraulic Pressure Control Pilot (PCP) valve controls pilot pressure to drive the servo piston, varying the swashplate angle and enabling continuous, stepless displacement adjustment from maximum forward to maximum reverse. The MS connector configuration with a control current range of 14–85 mA offers fast response — ideal for closed-circuit travel drive systems requiring frequent displacement changes and precise speed control.

2. 420 bar High-Pressure Capability and High Power Density

The Series 90 pump utilizes a parallel axial piston/slipper concept with a tiltable swashplate, achieving high-pressure output at 420 bar (42 MPa) rated pressure with 75 cm³/rev displacement. The compact pump body suits installation environments with limited engine compartment space in construction and agricultural machinery.

3. Integrated Charge Pump Simplifies Closed-Circuit Architecture

The pump integrates a charge pump (approximately 17 cc/rev), simultaneously handling closed-circuit boost flow, loop cooling circulation, and control pressure supply. This integrated design eliminates the need for an external standalone charge pump and associated piping, simplifying system architecture, reducing leakage risk, and saving installation space.

4. Smooth Neutral Transition and Bi-Directional Continuous Displacement

The swashplate tilts continuously in both directions, enabling stepless displacement variation from maximum forward to maximum reverse, with smooth flow direction change. Flow direction changes smoothly as the swashplate passes through neutral, delivering smooth reversing operation for travel drive systems. Both right-hand (90R) and left-hand (90L) rotation configurations are available to suit different equipment mounting requirements.

5. 100% Simulated Operating Condition Testing

Every pump undergoes a comprehensive factory test protocol: continuous operation at 420 bar rated pressure to verify volumetric and total efficiency, peak pressure cycling to validate housing and seal integrity, and full-speed-range verification (500–3950 rpm) of displacement control linearity and EDC control response. Test documentation is supplied with each unit.

Application Areas

• Construction Machinery: Excavator travel drive systems, wheel loader travel systems, road roller vibration and travel hydraulic drives

• Concrete Mixer Trucks: Mixer drum hydraulic drive systems (90R075 is a mainstream configuration for mixer trucks)

• Motor Graders: John Deere D/G series motor graders main hydraulic pump (670D–872G series)

• Agricultural Machinery: Tractor hydraulic drives, combine harvester travel systems, telehandler hydraulic drives

• Material Handling Equipment: Forklift and reach stacker hydraulic power systems

• Municipal Vehicles: Street sweeper and garbage compactor hydraulic drive systems

Expert Maintenance Tips

1. EDC Electro-hydraulic Proportional Control System Calibration and Maintenance

EDC control relies on precise matching of the electro-hydraulic Pressure Control Pilot (PCP) valve and servo piston. After pump or control module replacement, verify the control current (14–85 mA) to displacement relationship at rated speed and 50% displacement, confirming it falls within the factory calibration curve. MS connector wiring must strictly follow the Sauer Danfoss official wiring diagram to avoid reversed connections causing control malfunction. Control signal cables should use shielded cable with single-end shield grounding to prevent electromagnetic interference affecting control precision.

2. Charge Pump Suction Line Requirements

The integrated charge pump draws oil from the reservoir. Suction line diameter must accommodate the charge pump flow demand at 3600 rpm (approximately 17 cc/rev × 3600 rpm ≈ 61 L/min) to avoid negative pressure and cavitation. The suction inlet should sit at least 100 mm below the reservoir oil level. Inspect or replace the suction filter every 500 hours.

3. Mandatory Case Pre-Fill and Air Purging at First Installation

After installation, fill through the highest case port with clean hydraulic fluid filtered to ≤10 μm until oil overflows. Open the bleed plug and run the pump at idle until bubble-free oil flows continuously. For closed-circuit systems, perform low-pressure circulation with the charge pump running before applying load. Dry starting will cause catastrophic wear to the slipper and swashplate friction pair within seconds.

4. Fluid Cleanliness and Viscosity Control

Maintain system cleanliness at NAS 9 or ISO 18/16/13 or better. Recommended operating viscosity is ISO VG 46 or VG 68, with an optimum range of 14–50 cSt. Replace the system return filter at 200 hours for the first interval, then inspect or replace every 500 hours.

5. Pressure Setting Verification and Adjustment

The pump is configured with a pressure limiter (PL) and system pressure protection. Verify the accuracy of pressure settings every 2000 operating hours. Pressure adjustment should follow the Sauer Danfoss official technical manual: remove the plastic plug, loosen the lock nut (19 mm across flats for 90R075), and adjust pressure with a 5 mm Allen key. Never exceed the system maximum pressure setting.