Product Overview
The 90R100HS1CD80R3 is the 100 cc displacement variant of the Sauer Danfoss (now Danfoss Power Solutions) Series 90 heavy-duty closed-circuit axial piston pump line. Built on a cradle swash plate design, this pump is engineered exclusively for closed-loop hydrostatic drive systems. Flow rate is directly proportional to input speed and displacement, and the swash plate’s positive and negative angle capability reverses flow direction without requiring an external directional valve — enabling stepless speed control and bidirectional motor operation from a single pump.
This specific configuration, identified by the control code “HS1CD80R3,” carries a hydraulic servo displacement control (HS type) with defined port and pressure settings. It is a direct replacement for OEM Sauer Danfoss 90R100 pumps used in concrete mixer drum drives, road roller travel circuits, and compact-to-mid-size excavator main hydraulic systems.
As an interchangeability-focused replacement, this unit is assembled to the same tolerance stack as the original and subjected to 100% simulated-load bench testing before shipment. Dimensional envelope, mounting interface, and performance curves match the OEM specification, making it a true drop-in solution.
Technical Specifications
Model: 90R100HS1CD80R3
Series: Series 90 (R = Right-hand rotation)
Displacement: 100 cc/rev (6.10 in³/rev)
Design: Cradle swash plate axial piston variable displacement pump, closed circuit
Rated Continuous Pressure: 420 bar (42 MPa / 6000 psi)
Peak Pressure: 480 bar (48 MPa / 6960 psi)
Minimum Speed: 500 rpm
Rated Speed: 3300 rpm
Maximum Speed: 3650 rpm
Control Type: HS — Hydraulic servo displacement control
Charge Pump: Integral, with integrated high-pressure relief, flushing valve, and shuttle valve
Theoretical Torque: 1.59 Nm/bar (970 in·lb/1000 psi)
Weight: Approx. 60 kg
Housing Material: Cast iron
Data note: Pressure and displacement figures are based on Series 90 technical documentation for the 100 cc frame size and Danfoss published specifications. The “HS1CD80R3” segment of the model code defines control configuration, port arrangement, and pressure settings; final configuration should be verified against the unit nameplate or by submitting the original pump identification tag prior to order.
Key Technical Advantages
1. Cradle swash plate architecture delivers class-leading power density. The integral cast-iron housing and reinforced bearing set maintain swash plate rigidity under full system pressure, providing high resistance to vibration and particulate contamination in field conditions. The compact envelope suits space-constrained installations such as mixer truck engine compartments and compact wheel loader frames.
2. 420 bar continuous rating with 480 bar peak headroom. The 90R100 occupies the upper pressure tier of closed-circuit pumps, with sufficient margin to absorb the cyclic shock loading characteristic of mining equipment, vibratory rollers, and concrete mixer drum reversals.
3. Integrated charge pump and valve block simplify circuit design. The internal charge pump simultaneously supplies closed-loop makeup oil, system cooling flow, and control circuit pressure. Combined with the integrated high-pressure relief, flushing, and shuttle valves, the external circuit reduces to two high-pressure lines to the motor — fewer leak paths and simplified routing.
4. ≥92% volumetric efficiency reduces thermal load in continuous duty. Series 90 pumps maintain volumetric efficiency above 92% under rated conditions, with mechanical efficiency near 95%. In drum-drive and travel-drive applications with sustained duty cycles, this directly translates to lower oil temperature rise and reduced fuel consumption.
Application Areas
Concrete mixer trucks — 90R075/90R100 is the industry-standard drum drive displacement for mixer truck hydrostatic systems.
Single-drum and tandem vibratory rollers — full hydrostatic travel drive.
Compact to mid-size excavators — main pump or travel drive, compatible with Caterpillar and Hitachi hydraulic architectures.
Asphalt pavers and cold planers — travel and implement drive circuits.
Agricultural machinery — hydrostatic travel drive for large combine harvesters and forage harvesters.
Underground utility vehicles and heavy tracked carriers — heavy-duty closed-loop travel systems.
Expert Maintenance Tips
Pre-installation: Confirm shaft rotation direction (R = right-hand) matches the prime mover. Flush the suction line with clean hydraulic fluid before connection — particulate contamination is the leading cause of premature failure in closed-circuit piston pumps. The 90R100 requires fluid cleanliness of ISO 4406 20/18/15 or better.
First start-up: Pre-fill the pump housing with clean hydraulic fluid. Run at 500–800 rpm for 2–3 minutes to purge air, monitoring charge pressure until it stabilizes (normally 8–12 bar minimum). Only then ramp to operating speed.
Routine service: Monitor the charge pump filter differential pressure and replace the element at 2.5 bar ΔP. Maintain hydraulic fluid operating temperature between 30°C and 70°C; sustained operation above 80°C accelerates seal degradation and volumetric efficiency loss. Replace hydraulic fluid and filters every 2,000 operating hours or annually, whichever comes first.
Long-term storage: For idle periods exceeding three months, fill the pump housing with preservative hydraulic fluid, cap all ports, and store in a dry environment. Before returning to service, bench-test volumetric efficiency and pressure holding capability to confirm seal integrity.
