Sauer Danfoss Series 20 Axial Piston Pumps
The Danfoss Series 20 (Sundstrand S20) is a swash plate axial piston pump designed for hydrostatic transmissions in closed loop circuits. Eight frame sizes from 33 to 334 cm³/rev cover a wide range of drive system requirements, from compact utility vehicles to heavy industrial machinery. Reversible flow, servo displacement control, and a full-length tapered roller bearing arrangement make this a robust, field-proven choice where reliable power transmission is non-negotiable.
- Key Features
- Variable displacement swash plate design with infinitely adjustable flow in both directions
- Reversible flow — swash plate tilts through neutral to reverse without additional valving
- Hydro-mechanical servo control with automatic return to zero on handle release
- Full-length shaft with tapered roller bearing for high radial load capacity
- High case pressure capability with suitable shaft seals — no leakage even at low temperatures
- SAE four-bolt flange mounting; SAE split flange main pressure ports
- Clockwise or counterclockwise rotation (viewed from input shaft)
- Serviceable with standard hand tools; all sub-assemblies individually replaceable
- Available with integral charge pump
| Frame Size | Max Displacement (cm³/rev) | Max Displacement (in³/rev) | Min Speed (rpm) | Rated Speed (rpm) | Max Swash Plate Angle (degrees) | Mass Moment of Inertia - kg m2 x 10^-3 | Mass Moment of Inertia - lbf ft2 x 10^-3 |
| 033 | 33.3 | 2.03 | 500 | 3800 | 18 | 4.34 | 103 |
| 052 | 51.6 | 3.15 | 500 | 3500 | 18 | 8.14 | 193.2 |
| 070 | 69.8 | 4.26 | 500 | 3200 | 18 | 12.34 | 292.8 |
| 089 | 89 | 5.43 | 500 | 2900 | 18 | 17.77 | 421.7 |
| 119 | 118.7 | 7.24 | 500 | 2700 | 18 | 29.11 | 690.8 |
| 166 | 165.8 | 10.12 | 500 | 2400 | 18 | 50.19 | 1191 |
| 227 | 227.3 | 13.87 | 500 | 2100 | 18 | 86.8 | 2059.8 |
| 334 | 333.7 | 20.36 | 500 | 1900 | 18 | 161.4 | 3830 |
