151F0502 Danfoss OMS 125 Orbital Hydraulic Motor

Product Overview

The Danfoss OMS Series is a proven range of LSHT (Low-Speed High-Torque) orbital hydraulic motors designed for applications requiring reliable low-speed rotation, high starting torque and robust mechanical power transmission.

The configurations covered here include:

• OMS 125 — 151F0502
• OMS 160 — 151F0545
• OMS 200 — 151F0511

Danfoss currently lists OMS in its Power Solutions product archive as a historical Service Only product family while retaining technical and service documentation.

The OMS technical documentation covers displacement sizes from 80 to 500 cm³/rev. The three requested sizes are:

• OMS 125: 125.7 cm³/rev
• OMS 160: 159.7 cm³/rev
• OMS 200: 200.0 cm³/rev

They are fixed-displacement orbital motors in which hydraulic flow determines rotational speed while differential pressure determines available output torque.

For replacement applications, the complete part number must be verified because shaft, flange, port, seal and bearing configurations can differ even within the same OMS displacement class.

Technical Specifications

OMS 125 — 151F0502

• Brand: Danfoss / Sauer-Danfoss
• Series: OMS
• Motor Type: LSHT Orbital Hydraulic Motor
• Part Number: 151F0502
• Motor Size: OMS 125
• Geometric Displacement: 125.7 cm³/rev
• Displacement: 7.67 in³/rev
• Maximum Continuous Speed: 600 rpm
• Maximum Intermittent Speed: 720 rpm
• Maximum Continuous Torque: 375 Nm
• Maximum Intermittent Torque: 490 Nm
• Maximum Continuous Pressure Drop: 210 bar / 3,050 psi
• Maximum Intermittent Pressure Drop: 275 bar / 3,990 psi
• Peak Pressure: 295 bar / 4,280 psi
• Maximum Continuous Flow: 75 L/min
• Maximum Intermittent Flow: 90 L/min
• Maximum Continuous Output: 18.0 kW
• Maximum Intermittent Output: 22.5 kW
• Shaft: Ø32 mm cylindrical shaft
• Mounting: Standard four-hole flange
• Ports: G1/2
• Drain: G1/4
• Rotation: Bi-directional
• Approximate Weight: 10.3 kg

OMS 160 — 151F0545

• Brand: Danfoss / Sauer-Danfoss
• Series: OMS
• Motor Type: LSHT Orbital Hydraulic Motor
• Part Number: 151F0545
• Motor Size: OMS 160
• Geometric Displacement: 159.7 cm³/rev
• Displacement: 9.75 in³/rev
• Maximum Continuous Speed: 470 rpm
• Maximum Intermittent Speed: 560 rpm
• Maximum Continuous Torque: 490 Nm
• Maximum Intermittent Torque: 600 Nm
• Maximum Continuous Pressure Drop: 210 bar / 3,050 psi
• Maximum Intermittent Pressure Drop: 260 bar / 3,770 psi
• Peak Pressure: 280 bar / 4,060 psi
• Maximum Continuous Flow: 75 L/min
• Maximum Intermittent Flow: 90 L/min
• Shaft: 14-tooth spline, approximately 31.75 mm outside diameter
• Port: G1/2
• Mounting: Special flange
• Flange Centering Diameter: 82.5 mm
• Bolt-Circle Diameter: 106.4 mm
• Approximate Weight: 11.2 kg

OMS 200 — 151F0511

• Brand: Danfoss / Sauer-Danfoss
• Series: OMS
• Motor Type: LSHT Orbital Hydraulic Motor
• Part Number: 151F0511
• Motor Size: OMS 200
• Geometric Displacement: 200.0 cm³/rev
• Displacement: 12.20 in³/rev
• Maximum Continuous Speed: 375 rpm
• Maximum Intermittent Speed: 450 rpm
• Maximum Continuous Torque: 610 Nm
• Maximum Intermittent Torque: approximately 720 Nm
• Maximum Continuous Pressure Drop: 210 bar / 3,050 psi
• Maximum Intermittent Pressure Drop: 275 bar / 3,990 psi
• Maximum Continuous Flow: 75 L/min
• Maximum Intermittent Flow: 90 L/min
• Shaft: 1-1/4″ 14-tooth spline
• Shaft Center Tap: M8
• Mounting: Standard four-bolt square flange
• Pilot Diameter: 82.5 mm
• Bolt-Circle Diameter: 106.4 mm
• Port: G1/2 side port
• Drain: G1/4
• Front Bearing: Tapered roller bearing
• Rear Bearing: Tapered roller bearing
• Check Valve: Yes
• Shaft Seal: NBR
• Approximate Weight: 11.1 kg

Key Technical Advantages

1. LSHT High-Torque Architecture

The OMS platform is engineered around low-speed, high-torque operation rather than high-speed rotation.

For example, OMS 125 provides:

• 125.7 cm³/rev displacement
• 375 Nm continuous torque
• 600 rpm continuous maximum speed

This operating profile is particularly suitable for heavy rotary loads and applications requiring strong starting performance.

2. Three-Zone Orbital Motor Design

The OMS platform is characterized by reliable operation, high efficiency under pressure and a three-zone design.

The orbital powertrain converts hydraulic energy into rotary mechanical output through controlled internal commutation and gear engagement.

3. Heavy-Duty Roller Bearing Arrangements

Specific OMS configurations use roller or tapered roller bearings to accommodate external mechanical loading.

For example, 151F0511 uses tapered roller bearings at both the front and rear.

This is important for drives using:

• Sprockets
• Gears
• Wheels
• Pulleys
• Chain drives

4. Multiple Shaft and Mounting Configurations

The OMS family can be configured with:

• Cylindrical shafts
• Splined shafts
• Tapered shafts
• Standard flanges
• Special flanges
• Wheel-type mounting arrangements

The three requested part numbers demonstrate why complete-code matching is critical:

151F0502 → Ø32 mm cylindrical shaft

151F0545 → 14T spline + special flange

151F0511 → 1-1/4″ 14T spline + standard four-bolt flange

These should not be assumed to be mechanically interchangeable solely because they share the OMS family name.

5. Bi-Directional Operation

OMS motors can operate in either rotational direction by reversing the hydraulic flow.

This makes them suitable for:

• Winches
• Conveyors
• Augers
• Sweepers
• Wheel drives
• Rotary machinery

6. Shaft-Sealing Options

The OMS family was available with different shaft-sealing configurations, including high-pressure shaft seals for demanding applications.

Seal selection should therefore be based on the actual hydraulic pressure, external contamination and operating environment rather than assuming that every OMS configuration has the same shaft-seal specification.

Application Areas

OMS 125 — 151F0502

Typical applications include:

• Agricultural machinery
• Conveyor systems
• Textile machinery
• Machine tools
• Food-processing equipment
• Compact mobile equipment
• Auxiliary mining equipment

OMS 160 — 151F0545

Typical applications include:

• Agricultural machinery
• Forestry equipment
• Road machinery
• Material handling equipment
• Conveyor drives
• Sweepers
• Hydraulic winches
• Mobile hydraulic machinery

The special-flange and spline configuration of 151F0545 is particularly relevant to replacement applications requiring a specific mechanical interface.

OMS 200 — 151F0511

Typical applications include:

• Heavy conveyor drives
• Agricultural machinery
• Forestry machinery
• Industrial rotary equipment
• Hydraulic winches
• Sprocket drives
• Wheel drives
• Material handling systems
• Mobile machinery

The 1-1/4″ 14-tooth spline and roller-bearing configuration make 151F0511 suitable for rotary applications with significant mechanical loading.

Expert Maintenance Tips

1. Match the Complete Part Number

Never select an OMS replacement solely by displacement.

The following are distinct configurations:

151F0502
151F0545
151F0511

Shaft, flange and port configurations must be verified before installation.

2. Verify Shaft Alignment

During installation, check:

• Shaft concentricity
• Coupling alignment
• Pilot fit
• Mounting-face flatness
• Spline engagement

Poor alignment increases bearing load and can accelerate shaft-seal failure.

3. Calculate External Shaft Loads

For sprocket, pulley, gear or wheel applications, calculate:

Radial Load + Load Distance + Shaft Speed + Bearing Life

rather than evaluating the motor from torque rating alone.

4. Avoid Heavy Cold Starts

Low ambient temperature increases hydraulic-fluid viscosity and can raise pressure loss and starting friction.

Allow the hydraulic system to circulate and warm up under low load before applying full operating pressure.

5. Monitor Low-Speed Performance

The following symptoms can indicate internal wear or hydraulic problems:

• Reduced starting torque
• Speed fluctuation
• Excessive temperature
• Reduced output torque
• Increased internal leakage

Inspection should include the gear wheel set, commutation surfaces, shaft seal, bearings and hydraulic-fluid condition.

6. Perform 100% Simulated Operating-Condition Testing

For replacement OMS motors, our recommended factory QA program includes:

• Displacement verification
• Continuous-pressure testing
• Intermittent-pressure testing
• Flow testing
• Speed verification
• Starting-torque testing
• Continuous-torque testing
• Internal-leakage testing
• Rotation-direction testing
• Shaft runout inspection
• Bearing inspection
• Temperature-rise testing
• Noise and vibration inspection
• Complete configuration verification

The engineering objective is:

Drop-In Dimensional Interchangeability + Hydraulic Performance Equivalence + Long-Term Reliability