Powerful Fixed Displacement Piston Motor for High-Pressure and
High-Speed Application
Features:
1. Fixed motor with axial tapered piston rotary group of bent.axis
design, for hydrostatic drives in open and closed circuits.
2. For use in mobile and stationary applications.
3. The output speed is dependent on the flow of the pump and the
displacement of the motor.
4. The output torque increases with the pressure differential
between the high-pressure and the low-pressure side.
5. Finely graduated sizes permit far-reaching adaptation to
thedrive case.
6. High power density.
7. Small dimensions.
8. High total efficiency.
9. Good starting characteristics.
10. Economical design.
11. One-piece tapered piston with piston rings for sealing.
Technical data:
| Size | NG | 45 | 56 | 63 | 80 | 90 | 107 | 125 | 160 | 180 |
| Displacement geometric, per revolution | Vg | cm3 | 45.6 | 56.1 | 63 | 80.4 | 90 | 106.7 | 125 | 160.4 | 180 |
| Speed maximum | nnom | rpm | 5600 | 5000 | 5000 | 4500 | 4500 | 4000 | 4000 | 3600 | 3600 |
| nmax | rpm | 6200 | 5500 | 5500 | 5000 | 5000 | 4400 | 4400 | 4000 | 4000 |
| Input flow at nnom and Vg | qV | L/min | 255 | 281 | 315 | 362 | 405 | 427 | 500 | 577 | 648 |
Torque
at Vg and | Δp = 350 bar | T | Nm | 254 | 313 | 351 | 448 | 501 | 594 | 696 | 893 | 1003 |
| Δp = 400 bar | T | Nm | 290 | 357 | 401 | 512 | 573 | 679 | 796 | 1021 | 1146 |
| Rotary stiffness | c | kNm/rad | 4.18 | 5.94 | 6.25 | 8.73 | 9.14 | 11.2 | 11.9 | 17.4 | 18.2 |
| Moment of inertia for rotary group | JGR | kgm2 | 0.0024 | 0.0042 | 0.0042 | 0.0072 | 0.0072 | 0.0116 | 0.0116 | 0.022 | 0.022 |
| Maximum angular acceleration | a | rad/s2 | 14600 | 7500 | 7500 | 6000 | 6000 | 4500 | 4500 | 3500 | 3500 |
| Case volume | V | L | 0.33 | 0.45 | 0.45 | 0.55 | 0.55 | 0.8 | 0.8 | 1.1 | 1.1 |
| Mass (approx.) | m | kg | 13.5 | 18 | 18 | 23 | 23 | 32 | 32 | 45 | 45 |
Specifications:
Warranty | 12 months |
Transport Package | Standard Export Wooden Case |
Certification | ISO9001: 2000 |
Type | Construction machinery piston motor |
Production Capacity | 2000-3000 pcs/month |
HS Code | 8412299090 |
Application | Aerial work platform, road roller |
| Maximum torque | 1273 Nm |
Delivery Time | 15-30 Days after Payment |
| Displacemen | 45-180cc |
Applications:
1. Hydraulic swing system for excavators: The bent-axis design and 450 bar intermittent pressure output
enable A2FM to provide dynamic torque compensation during frequent
start-stop cycles on excavator swing platforms. Its compact axial
length (20% shorter) fits confined spaces, reducing pressure loss
from pipeline bending. Modular SAE flange ports allow rapid
replacement, cutting maintenance downtime by over 30%.
2. Drum drive for concrete mixer trucks: A2FM’s maximum torque output (3000 Nm) ensures aggregate mixing
uniformity under low-speed heavy loads, with speed fluctuation rate
<2%. Shock-resistant bearings withstand periodic load impacts
during concrete curing. Closed-loop charge pumps maintain oil
cleanliness at ISO 4406 20/18, extending oil change intervals to
2000 hours.
3. Hoisting mechanism for mobile cranes: With 92% starting torque efficiency and bidirectional rotation,
A2FM achieves hook acceleration error <0.1 m/s² during heavy
load lifting. Modular flange ports simplify multi-pump
coordination, reducing hydraulic pipeline complexity by 30%.
Enhanced seals prevent oil leakage during inclined operations,
limiting system pressure fluctuations to ±5 bar.
4. Travel drive for port container cranes: Power density of 1.2 kW/kg meets high-power drive demands,
achieving travel speed control accuracy of ±2% for varying
container loads.
5. Cutter drive for agricultural harvesters: Wide temperature range (-40°C~+90°C) ensures continuous operation
in extreme field conditions, reducing failure rates by 40%.
Dust-resistant seals block straw debris ingress, extending grease
replacement intervals to 1000 hours and cutting maintenance costs
by 50%.
Competitive Advantage:
1. The bent-axis axial piston motor utilizes 40° angular alignment
to optimize torque transmission paths, with rigid piston-driveshaft
connections maintaining 95% mechanical efficiency under 450bar peak
pressure, ideal for heavy-duty start-stop applications like
concrete mixer drum drives.
2. The integral piston ring design with double-sealing barriers
resists contaminants ≤15μm, achieving 20,000-hour maintenance-free
operation under NAS 1638 Class 9 oil cleanliness, drastically
reducing mine equipment maintenance costs.
3. With modular flanges compliant to ISO 3019-2 and SAE J744
standards, the hydraulic motor enables rapid planetary gearbox
replacement on marine deck machinery, reducing port equipment
downtime by 50%.
4. Equipped with temperature-compensation valves, the axial piston
motor automatically adjusts oil viscosity from -40℃ to +80℃,
maintaining ≤±2% torque stability for wind turbine pitch systems in
polar conditions.
5. Achieving 3.2kW/kg power density with aluminum alloy housing
reduces robotic joint drive unit weight by 18% while meeting EN
15000 safety standards, enhancing agile material handling
performance.
The Analysis For Rexroth A2FM Fixed Displacemen Piston Motor Common
Breakdown:
1. Swashplate Angle Deviation Causes Torque Fluctuation: Spring
preload reduction or foreign object jamming in variable mechanism
leads to swashplate angle deviation. Symptoms include >±5%
torque fluctuation under constant pressure. Solution involves
disassembling piston chamber, replacing 50μm orifice filters, and
recalibrating neutral sensor.
2. Piston Abnormal Wear Reduces Volumetric Efficiency: Over 15μm
clearance between piston and cylinder under NAS 10 contaminated oil
causes <85% efficiency. Restore oil to NAS 7 via offline
filtration and replace hard-chrome plated pistons.
3. Scratched valve Plate Induces Pressure Pulsation: Metal debris
(>20μm) in porting area causes >±10bar pressure ripple at
350bar. Regrind port plate to Ra0.2μm and install ≥95% efficient
magnetic return filters.
4. Excessive Bearing Clearance Triggers Mechanical Vibration:
Conical roller bearing clearance >0.08mm causes >5m/s² radial
vibration. Adjust preload to 120-150N·m with hydraulic tensioner
and relubricate with NLGI 2 grease.
5. Inadequate Housing Cooling Causes Oil Overheat:Dust
accumulation (>2mm) on fins leads to >90℃ oil temperature at
300bar/50℃ ambient. Clean fins with 0.6MPa air and add auxiliary
fans (≥6m/s airflow).
