Vickers Hydrokraft MFX and MFW Series Motors
Vickers Hydrokraft MFX and MFW motors are fixed-displacement axial piston motors of swashplate design, suitable for hydrostatic drives. MFX covers the smaller frame sizes, from 66 to 180 cm³/rev; MFW covers the larger sizes, from 250 to 750 cm³/rev. Both series share the same pressure and speed ratings, and are engineered with oversized shaft bearings for long life and thru-drive capability.
Rotating and pressure-loaded parts are pressure-balanced, giving high efficiency and smooth, low-noise operation, and automatic wear compensation makes both series highly resistant to dirt and debris. A range of control options are available on the variable-displacement MVX and MVW equivalents of these frames; MFX and MFW themselves are supplied without displacement control.
Both series are rated to 350 bar continuous and 420 bar maximum pressure, at speeds up to 1800 rev/min (1500 rev/min on the largest MFW-750 size). Combination (tandem) units are available, foot-mounted only, allowing two motor sections to be driven from a single input.
MFX and MFW motors run on standard mineral hydraulic oil, and can also be specified for water-in-oil emulsion, water glycol, phosphate ester or polyol ester fluids, subject to reduced pressure, speed or bearing life depending on fluid type; see Fluid Compatibility below.
Key Specifications
| Specification | Detail |
| Technology | Axial piston, fixed displacement, swashplate design |
| Series | MFX, current PowerSource “X series motors” category (66-180 cm³/rev), MFW, current PowerSource “W series motors” category (250-750 cm³/rev) |
| Displacement range | 66 to 750 cm³/rev (4.0 to 45.8 in³/rev) |
| Nominal pressure (100% duty cycle) | 350 bar (5,075 psi) |
| Maximum pressure (to DIN 24312) | 420 bar (6,090 psi); pressure can be applied to the motor outlet, but the sum of inlet and outlet maximum pressure must not exceed 420 bar |
| Speed range | 80 to 1800 rev/min (MFX and MFW 250/360/500); 80 to 1500 rev/min (MFW 750); higher speeds available on request |
| Direction of rotation | Bi-directional |
| Mounting | Flange or foot-mounted; combination (tandem) units foot-mounted only |
| Ambient temperature range | -20 to +50°C (-4 to +122°F) |
| Hydraulic fluid | Mineral oil to DIN 51524 part 2; alternative fluids available, see Fluid Compatibility below |
| Hydraulic fluid temperature range | -25°C on start-up, +90°C maximum (-13°F on start-up, +194°F maximum) |
| Viscosity range (continuous operation) | 10 to 75 cSt |
| Maximum permissible start viscosity | 1000 cSt |
| Fluid cleanliness | ISO 4406 18/15/13 or better; operation in more contaminated fluid is not recommended |
| Case pressure | Maximum 0.5 bar above minimum output pressure; 4 bar absolute (6 bar absolute with special shaft seal) |
Model Range
| Model | Displacement, cm³/rev | Weight, kg (lb) | Mass of inertia, kg m² | Max. driving torque, Nm (lb.ft) | Max. power at max. speed, kW (hp) |
| MFX-066 | 66 | 55 (121) | 0.016 | 441 (325) | 83 (112) |
| MFX-090 | 90 | 75 (165) | 0.016 | 602 (444) | 114 (152) |
| MFX-130 | 130 | 106 (234) | 0.045 | 869 (640) | 164 (220) |
| MFX-180 | 180 | 114 (251) | 0.045 | 1203 (887) | 227 (304) |
| MFW-250 | 250 | 212 (467) | 0.146 | 1670 (1232) | 307 (422) |
| MFW-360 | 360 | 220 (485) | 0.152 | 2405 (1774) | 454 (608) |
| MFW-500 | 500 | 340 (750) | 0.5 | 3340 (2463) | 630 (845) |
| MFW-750 | 750 | 395 (871) | 0.55 | 5000 (3688) | 787 (1056, at 1500 rpm) |
Combination (tandem) unit maximum driving torque, splined shaft only: 2×441 Nm (MFX-066), 2×602 Nm (MFX-090), 2×869 Nm (MFX-130), 2×1203 Nm (MFX-180), 2×1670 Nm (MFW-250), 2×2405 Nm (MFW-360), 5000 Nm (MFW-500 and MFW-750, shaft-limited rather than doubled).
Fluid Compatibility
Where an alternative fluid is used, maximum pressure, speed and expected bearing life may be reduced, as set out below.
| Fluid type | Class | Max. pressure | Max. speed | Seal material | Max. temp. | Bearing life |
| Water-in-oil emulsion | HFB | 250 bar | 1800 rpm | Fluorocarbon | 49°C | 50% of standard bearing life |
| Water glycol | HFC | 250 bar | 1800 rpm | Fluorocarbon | 49°C | 25% of standard bearing life |
| Phosphate ester | HFDR | 350/420 bar | 1800 rpm | Fluorocarbon | 66°C | 100% of standard bearing life |
| Polyol ester | HFDU | 350/420 bar | 1800 rpm | Fluorocarbon | 66°C | 100% of standard bearing life |
Typical Applications
- Pulp and paper chemical pump drives
- Primary metals
- Marine winches
- Mixers
Downloads
The following manuals are available from Danfoss for service and maintenance reference:
- Vickers Hydrokraft Piston Pumps and Motors ATEX/UKEX Technical Information
- For more downloads visit Danfoss Power Source
Contact Us for further technical details and configuration options.