MMF035DAAGCGNNR MMF044DAFHABNNN Danfoss Series 40 Axial Piston Motor

Product Overview

The MMF series axial piston motors are a proven product line within the Danfoss (formerly Sauer-Danfoss) Series 40 platform, specifically engineered for closed-circuit hydrostatic transmissions in medium-power mobile and industrial applications. Designed to fully comply with Danfoss MMF series mounting and interface standards, these motors offer 100% direct interchangeability with original Danfoss units—enabling plug-and-play replacement without any管路 modifications or adapter plates, significantly minimizing downtime and retrofit costs.

The MMF series features a swashplate-type axial piston design, delivering high power density within a compact, standardized footprint. The MMF035 and MMF044 are fixed displacement motors, maintaining a constant ratio between fluid flow and output shaft speed for reliable, stable power delivery. Every unit undergoes 100% factory testing under simulated real-world working conditions, validating pressure, flow, volumetric efficiency, and noise performance before shipment—ensuring reliable operation from the very first start.

Model Code Interpretation (using MMF044DAFHABNNN as an example):

Technical Specifications 

The MMF series covers multiple displacement options including MMF025, MMF035, MMF044, and MMF046. Below are the core specifications for MMF035DAAGCGNNR and MMF044DAFHABNNN:

MMF035DAAGCGNNR

• Model: MMF035DAAGCGNNR

• Type: Fixed displacement axial piston motor

• Displacement: 35 cm³/rev (2.14 in³/rev)

• Rated Pressure: 34.5–38 MPa (345–380 bar)

• Maximum Pressure: 38.5–41.5 MPa (385–415 bar)

• Rated Speed: 3300–4000 r/min

• Maximum Speed: 3300–5300 r/min

• Case Pressure (Continuous): 1.7 bar (25 psi)

• Case Pressure (Peak): 5.2 bar (75 psi)

• Weight: Approx. 11 kg

• Mounting: SAE B flange

• Port Options: Side, axial, or twin ports

• Shaft Options: Splined, tapered, or keyed (varies by configuration)

• Medium: Hydraulic oil

• Operating Temperature Range: 30–90℃

MMF044DAFHABNNN

• Model: MMF044DAFHABNNN

• Type: Fixed displacement axial piston motor

• Displacement: 44 cm³/rev (2.65 in³/rev)

• Rated Pressure: 34.5–38 MPa (345–380 bar)

• Maximum Pressure: 38.5–41.5 MPa (385–415 bar)

• Rated Speed: 3300–4000 r/min

• Maximum Speed: 3300–5300 r/min

• Case Pressure (Continuous): 1.7 bar (25 psi)

• Case Pressure (Peak): 5.2 bar (75 psi)

• Weight: Approx. 11 kg

• Mounting: SAE B flange

• Port Options: Side, axial, or twin ports

• Shaft Options: Splined, tapered, or keyed

• Medium: Hydraulic oil

• Operating Temperature Range: 30–90℃

Key Technical Advantages

1. 100% Direct Interchangeability – Zero Modification Required
The MMF series is engineered to exact Danfoss Series 40 mounting and interface specifications, with identical dimensions, port locations, and shaft end configurations. End users can replace original units directly without any管路 modifications or adapter plates—transforming unplanned downtime into scheduled, rapid maintenance while significantly reducing spare parts procurement costs and equipment downtime losses.

2. Swashplate Axial Piston Design with High Power Density
The proven swashplate axial piston configuration delivers exceptional power density within the compact SAE B mounting footprint. Compared to other motor types of equivalent displacement, the MMF series offers a smaller physical footprint and lighter weight (just 11 kg), facilitating installation in space-constrained mobile equipment.

3. Broad Speed and Pressure Operating Range
Rated speeds span 3300–4000 r/min with maximum speeds up to 5300 r/min, while rated pressures range from 34.5–38 MPa and peak pressures reach 38.5–41.5 MPa. This wide operating envelope enables the MMF series to reliably handle diverse high-load, high-speed continuous operation requirements.

4. Flexible Configuration Options
The series offers SAE B standard flange mounting, multiple port configurations (side, axial, twin), and various shaft options including splined, tapered, and keyed types. Optional loop flushing functionality is available to effectively reduce oil temperature in closed-circuit systems, extending motor and system service life.

5. 100% Factory Testing Under Simulated Working Conditions
Every MMF series unit undergoes rigorous factory testing under simulated real-world conditions, validating pressure, flow, volumetric efficiency, noise levels, and thermal characteristics across the full speed range. Test media match actual operating conditions, ensuring each unit is ready for immediate installation and reliable operation upon delivery—eliminating the risk of “dead on arrival” components.

Application Areas

The MMF series axial piston motors are widely deployed across the following industries and equipment types:

• Road Construction Equipment: Wirtgen W 100/W 120 milling machines, Vögele Super 1300-2/1600-2 pavers, Hamm HD 8/HD 10 rollers

• Construction Machinery: Caterpillar 301.7D/302.2D/302.7D/303.5E mini-excavators, 226D/232D skid-steer loaders

• Agricultural Machinery: John Deere 3025E/3038E/3045R tractors, Claas Nexos 210/Elios 210 combines

• Compaction Equipment: Bomag BW 80/90/100/120, BW211/BW213/BW220 tandem rollers

• Compact Loaders: JCB 8018CTS/8026CTS/8030ZTS mini-excavators, 55Z-1/57C-1/155 wheel loaders

• Forestry Machinery: John Deere Forestry 810E forwarders, Ponsse Gazelle light forwarders

• Aerial Work Platforms: Genie, Haulotte, JLG compact lifting platforms

Expert Maintenance Tips

1. Hydraulic Fluid Cleanliness Management
The MMF series utilizes swashplate axial piston designs with minimal clearances between pistons and cylinder bores, making them highly sensitive to fluid contamination. It is recommended to install return line filters with ≤10μm filtration rating, maintaining fluid cleanliness to ISO 4406 18/13 or better. Never use degraded or substandard hydraulic fluids.

2. Case Pressure Monitoring
The MMF series case continuous working pressure must not exceed 1.7 bar (25 psi) , with peak pressure limited to 5.2 bar (75 psi) . Excessive case backpressure will lead to shaft seal damage and premature bearing failure. Ensure adequate return line sizing with no flow restrictions, and route the case drain line directly back to the reservoir.

3. Air Bleeding and Pre-filling Before Start-up
Always bleed air from the motor housing via the highest vent port before initial start-up or after extended shutdown periods to prevent cavitation damage. Ensure the motor housing is completely filled with hydraulic fluid prior to starting—this can be achieved by pre-filling through the case drain port.

4. Coupling Alignment Requirements
Maintain shaft alignment within 0.05 mm concentricity and 0.5° angular deviation between the drive shaft and the load shaft. Excessive misalignment will lead to premature bearing wear and shaft seal leakage. The use of flexible couplings is recommended to compensate for minor installation deviations.

5. Periodic Inspection and Maintenance
Inspect shaft seals for leakage and listen for abnormal operating noise every 1,000 operating hours or every 6 months (whichever comes first). If reduced volumetric efficiency or insufficient output torque is observed, timely overhaul of the piston assembly and valve plate is recommended.