TECHNICAL WHITE PAPER
HANJIU OMR Series
Orbital Motor
Danfoss OMR Compatible | Medium Duty | Roller Gear Ring Design
OMR 50 · 80 · 100 · 125 · 160 · 200 · 250 · 315 · 375 · 400
Shijiazhuang Hanjiu Technology Co., Ltd.
June 2025 | www.hjhydraulic.com
Table of Contents
Executive Summary................................................................................. 3
Chapter 1 OMR Series: Medium-Duty Orbital Motor Technology.............. 4
1.1 Gerotor Mechanism with Roller Gear Ring..................................... 4
1.2 OMR vs OMP: Key Differentiators................................................. 5
Chapter 2 HANJIU OMR Complete Technical Specifications...................... 6
2.1 Ten-Model Displacement Range................................................... 6
2.2 Performance Data Table............................................................... 7
2.3 Pressure, Torque and Speed Envelope.......................................... 8
Chapter 3 Cross-Reference and Compatibility Guide................................ 9
3.1 HANJIU OMR vs Danfoss OMR Cross-Reference............................. 9
3.2 Multi-Brand Interchangeability................................................... 10
Chapter 4 Spare Parts, Seal Kits and Service Solutions............................ 11
4.1 Core Spare Parts Catalog............................................................ 11
4.2 Maintenance Cost Optimization.................................................. 12
Chapter 5 Applications Across Industries............................................... 13
Chapter 6 Quality Assurance and Global Distribution............................. 15
Chapter 7 Ordering Guide and Technical Support................................... 17
Conclusion............................................................................................ 19
References............................................................................................ 20
Executive Summary
The HANJIU OMR series medium-duty orbital hydraulic motor delivers enhanced power density and superior bearing capacity for applications demanding greater torque output and longer service life than standard light-duty alternatives. Positioned between the compact OMP series and the heavy-duty OMS/OMT families, the OMR series integrates a roller gear ring mechanism with robust bearing support to handle substantially higher radial and axial shaft loads. This white paper presents the complete HANJIU OMR product line covering ten displacement variants from OMR 50 through OMR 400, with comprehensive technical specifications, cross-reference data, and aftermarket support information.
Shijiazhuang Hanjiu Technology Co., Ltd. has engineered its OMR series orbital motors to achieve complete dimensional and performance interchangeability with the Danfoss OMR series, the globally recognized benchmark for medium-duty hydraulic power transmission. With maximum continuous pressure ratings reaching 175 bar, peak torque output up to 580 Nm, and a versatile range of mounting flange, shaft, and port configurations, HANJIU OMR motors provide a cost-effective, readily available alternative for OEM equipment manufacturers, hydraulic system integrators, and aftermarket service providers worldwide.
Keywords: HANJIU OMR orbital motor, medium duty hydraulic motor, Danfoss OMR compatible, roller gear ring orbital motor, OMR 50 OMR 80 OMR 100 OMR 125 OMR 160 OMR 200 OMR 250 OMR 315 OMR 375 OMR 400, low speed high torque hydraulic motor, construction machinery hydraulic motor, agricultural equipment hydraulic motor, hydraulic motor spare parts, orbital motor seal kit
Chapter 1 OMR Series: Medium-Duty Orbital Motor Technology
1.1 Gerotor Mechanism with Roller Gear Ring
The OMR series orbital motor, like all gerotor-type hydraulic motors, converts fluid power into mechanical rotation through the interaction of an internally toothed stator ring and an externally toothed rotor. The defining innovation of the OMR design is the incorporation of a roller gear ring: cylindrical rollers are seated in the stator tooth pockets, creating a rolling contact interface with the rotor teeth rather than the sliding contact found in standard designs.
This roller gear ring architecture delivers significant performance benefits that distinguish the OMR from lighter-duty alternatives. Rolling contact reduces friction and mechanical wear, extending operational life under continuous high-pressure conditions. The roller distribution increases the effective contact area, enabling higher torque transmission capacity. Reduced internal friction improves overall mechanical efficiency, particularly at elevated operating pressures. The robust gearset construction tolerates higher return pressures without requiring external drain lines, simplifying hydraulic system design.
Hydraulic fluid enters through the precision-machined distributor valve (spool valve), which is integrated with the output shaft. The valve sequentially opens and closes flow passages to the expanding and contracting chambers formed between the rotor and stator teeth. As hydraulic pressure acts on the rotor, it executes a compound motion: orbital travel around the stator's geometric center combined with rotation about its own axis. A fixed ring gear mechanism translates this orbital-rotary motion into pure shaft rotation, delivering smooth, high-torque output at low speeds.
1.2 OMR vs OMP: Key Differentiators
While the OMP and OMR series share the same fundamental gerotor operating principle, the OMR incorporates structural enhancements that elevate it to a higher performance class. Understanding these differences enables equipment designers to select the optimal motor for each application requirement.
● Bearing capacity: OMR motors feature larger, more robust shaft bearings capable of sustaining significantly higher radial and axial loads, making them suitable for direct-drive applications without additional external bearing support
● Roller gear ring: the OMR's roller-equipped stator ring provides superior wear resistance and higher mechanical efficiency compared to the OMP's sliding-contact design, especially under sustained high-pressure operation
● Pressure rating: OMR motors achieve maximum continuous pressure of 175 bar with peak capability to 200 bar, compared to 140 bar continuous for most OMP models
● Mounting options: OMR motors offer both A2 oval flange and C square flange configurations, providing greater installation flexibility than the OMP's standard A2 flange
● Shaft options: the OMR accommodates larger shaft diameters including 32 mm cylindrical, 1-1/4 inch splined, and tapered shafts for higher torque transmission
● Overall dimensions: the OMR is approximately 20% larger and heavier than the corresponding OMP model, reflecting the increased structural capacity
Chapter 2 HANJIU OMR Complete Technical Specifications
2.1 Ten-Model Displacement Range
The HANJIU OMR series encompasses ten displacement models providing continuous torque from 65 Nm to 580 Nm. Each model number corresponds to the nominal geometric displacement in cubic centimeters per revolution. The product range is structured to cover medium-duty applications from compact agricultural implements through heavy construction equipment:
| OMR 50 | OMR 80 | OMR 100 | OMR 125 | OMR 160 | OMR 200 | OMR 250 | OMR 315 | OMR 375 | OMR 400 |
| 51.6 cm³ | 80.3 cm³ | 99.8 cm³ | 125.6 cm³ | 159.6 cm³ | 199.1 cm³ | 248.5 cm³ | 311.7 cm³ | 372.7 cm³ | 397.0 cm³ |
2.2 Performance Data Table
The following table presents continuous-duty performance specifications for all HANJIU OMR series orbital motors. All values are measured at 140 bar working pressure with ISO VG 46 mineral hydraulic oil at 50 degrees C. Intermittent ratings (peak duty not exceeding 10% of cycle time) permit pressure up to 200 bar:
| Model | Disp. | Speed | Torque | Power | Press. | Flow | Back Pr. |
| OMR 50 | 51.6 | 810 | 65 | 5.0 | 175 | 40 | 100 |
| OMR 80 | 80.3 | 625 | 108 | 6.5 | 175 | 50 | 100 |
| OMR 100 | 99.8 | 500 | 135 | 6.8 | 175 | 50 | 100 |
| OMR 125 | 125.6 | 400 | 168 | 6.8 | 175 | 50 | 100 |
| OMR 160 | 159.6 | 310 | 215 | 6.8 | 175 | 50 | 100 |
| OMR 200 | 199.1 | 250 | 270 | 6.8 | 175 | 50 | 100 |
| OMR 250 | 248.5 | 200 | 335 | 6.8 | 175 | 50 | 100 |
| OMR 315 | 311.7 | 160 | 420 | 6.8 | 175 | 50 | 100 |
| OMR 375 | 372.7 | 150 | 580 | 8.5 | 175 | 60 | 100 |
| OMR 400 | 397.0 | 155 | 520 | 8.0 | 175 | 60 | 100 |
2.3 Pressure, Torque and Speed Envelope
The HANJIU OMR series delivers a maximum continuous pressure of 175 bar across all models from OMR 50 through OMR 400, with an intermittent peak pressure of 200 bar for short-duration overload conditions. Maximum operating speed varies inversely with displacement, from 810 rpm for the OMR 50 down to 155 rpm for the OMR 400, maintaining optimal fluid film lubrication across all operating points.
Maximum output torque at continuous duty reaches 580 Nm for the OMR 375, with the OMR 400 delivering 520 Nm. Starting torque averages 85% to 90% of rated continuous torque, ensuring reliable startup under heavy load without auxiliary mechanisms. All models maintain high volumetric efficiency (typically 90% to 95%) across their specified speed and pressure ranges, with overall efficiency exceeding 80% at optimum operating points.
Maximum permissible back pressure on the return line reaches 100 bar when the high-pressure shaft seal (HPS) option is specified, eliminating the need for external drain connections in most closed-loop and regenerative circuit applications. Standard shaft seal configurations permit 50 bar maximum return pressure.
Chapter 3 Cross-Reference and Compatibility Guide
3.1 HANJIU OMR vs Danfoss OMR Cross-Reference
HANJIU OMR series orbital motors (also marketed as BMR/BM2 in select regions) achieve complete dimensional and functional interchangeability with the Danfoss OMR series. The following cross-reference table enables precise model matching for replacement, retrofit, and new equipment design applications:
| HANJIU Model | Danfoss Model | HANJIU BMR Code | Compatibility Notes |
| OMR 50 | OMR 50 | BMR 50 | Direct replacement, A2 and C flange |
| OMR 80 | OMR 80 | BMR 80 | 151-0700 / 151-0711 cross-match |
| OMR 100 | OMR 100 | BMR 100 | Popular for agriculture and construction |
| OMR 125 | OMR 125 | BMR 125 | 151-0713 / 151-0723 cross-match |
| OMR 160 | OMR 160 | BMR 160 | 151-0704 / 151-0714 cross-match |
| OMR 200 | OMR 200 | BMR 200 | 151-0705 / 151-0715 cross-match |
| OMR 250 | OMR 250 | BMR 250 | High-torque forestry and mining |
| OMR 315 | OMR 315 | BMR 315 | 151-0707 / 151-0717 cross-match |
| OMR 375 | OMR 375 | BMR 375 | 151-0718 cross-match |
| OMR 400 | OMR 400 | BMR 400 | Largest OMR displacement available |
Every HANJIU OMR motor undergoes comprehensive dimensional inspection, pressure testing at 1.5 times rated pressure, and performance validation before shipment. Mounting flange dimensions, shaft geometry, port thread specifications, and overall envelope dimensions conform precisely to Danfoss OEM standards, ensuring direct drop-in replacement without modification to existing equipment or hydraulic systems.
3.2 Multi-Brand Interchangeability
Beyond Danfoss compatibility, HANJIU OMR series motors serve as direct replacements for the following major international brands, providing distributors and service organizations with a single-source solution for diverse aftermarket requirements:
● M+S Hydraulic (Bulgaria) MR and MRS series medium-duty orbital motors
● Eaton Char-Lynn S series and 2000 series low speed high torque motors
● Parker / White Drive TG and WP series medium-duty motors
● SAM Brevini BGH and BMR series orbital motors
● Ross TRW MD and ME series hydraulic motors
● Bosch Rexroth MCR03 and MCR05 series gerotor motors
This broad cross-brand interchangeability positions HANJIU as a universal solution provider for medium-duty orbital motor replacement, reducing inventory complexity for distributors and ensuring rapid fulfillment for maintenance facilities serving mixed-equipment fleets.
Chapter 4 Spare Parts, Seal Kits and Service Solutions
4.1 Core Spare Parts Catalog
HANJIU maintains a comprehensive inventory of genuine replacement parts for the entire OMR series, supporting preventive maintenance programs and field repair operations with guaranteed-fit components. The spare parts catalog includes:
| Part Description | HANJIU Part Code | Application |
| Complete Seal Kit (Standard) | SK-OMR-STD | All OMR models, standard shaft seal |
| Complete Seal Kit (HPS) | SK-OMR-HPS | All OMR models, high-pressure shaft seal |
| Gerotor Set (Rotor + Stator + Rollers) | GS-OMR-XXX | Model-specific roller gear ring set |
| Distributor Valve / Spool Valve | DV-OMR-STD | Standard valve plate, all models |
| Output Shaft (Cylindrical 25mm) | OS-OMR-C25 | Standard shaft option |
| Output Shaft (Cylindrical 32mm) | OS-OMR-C32 | Heavy-duty shaft option |
| Output Shaft (Splined 1 inch) | OS-OMR-S1 | High torque transmission |
| Output Shaft (Tapered 1:8) | OS-OMR-T18 | Precision coupling applications |
| Needle Bearing Set | NB-OMR-SET | OMRW wheel motor variants |
| Slide Bearing Set | SB-OMR-SET | Standard bearing configuration |
| Mounting Flange Gasket | MF-OMR-A2C | A2 oval and C square flange gasket |
4.2 Maintenance Cost Optimization
Implementing HANJIU OMR orbital motors and genuine spare parts delivers measurable cost advantages throughout the equipment ownership lifecycle:
● Acquisition cost reduction of 35% to 55% compared to original Danfoss equipment, with equivalent performance and verified service life
● Complete seal kit pricing 40% to 60% below OEM levels, with all kits containing precision-matched seals, O-rings, and gaskets for one-complete overhaul
● Standard delivery lead times of 1 to 7 days worldwide, with 24-hour express dispatch available for emergency requirements
● Total cost of ownership reduction of 25% to 35% achieved through consistent parts availability, extended motor service life, and reduced downtime
● Free technical consultation provided by qualified hydraulic engineers with average response time under 2 hours
Chapter 5 Applications Across Industries
The HANJIU OMR series medium-duty orbital motor serves a diverse portfolio of applications across multiple industry sectors, leveraging its enhanced bearing capacity, higher pressure rating, and proven durability under demanding operating conditions.
5.1 Construction and Earthmoving Equipment
Construction machinery represents the largest application segment for OMR series orbital motors. Typical installations include skid-steer loader and compact track loader wheel drives, mini-excavator swing drives and boom articulation systems, backhoe loader loader arm and backhoe bucket drives, road roller drum vibration and propulsion systems, concrete mixer drum rotation drives, and aerial work platform lift and slew mechanisms. The OMR 80 through OMR 250 models predominate in construction applications, where the roller gear ring design provides the durability needed for continuous high-torque operation in dusty, high-vibration environments.
5.2 Agricultural and Turf Care Machinery
Agricultural equipment utilizes OMR motors for functions including combine harvester reel drives and auger systems, tractor front-loader lift and crowd operations, forage harvester header and feedroll drives, center-pivot and lateral-move irrigation system propulsion, vineyard and orchard sprayer fan and pump drives, and livestock feed mixer wagon and TMR mixer drives. The OMR's superior bearing capacity makes it particularly well-suited to agricultural applications where side loading from long implements and uneven terrain subjects the motor shaft to significant radial forces.
5.3 Forestry, Mining and Marine Applications
In the forestry sector, OMR motors power log forwarder crane drives, harvester head rotation and feed systems, and delimber arm actuators. Mining applications include underground LHD vehicle traction and bucket drives, roof bolter rotation mechanisms, and portable conveyor systems. Marine installations encompass anchor winch drives, capstan operations, stern ramp and hatch cover actuators, and commercial fishing net and line haulers. The larger displacement models including OMR 250, OMR 315, OMR 375, and OMR 400 provide the substantial torque required by these heavy-duty mobile equipment applications.
5.4 Industrial and Material Handling Equipment
Industrial applications span conveyor belt drives, mixing and blending equipment, rotary indexing tables, plastic injection mold handling, automated guided vehicle propulsion, forklift mast lift and tilt drives, automated storage and retrieval system mechanisms, and textile machinery rotation systems. The OMR's ability to operate with high return pressure without drain connection (when equipped with HPS seal) makes it particularly advantageous in closed-loop and regenerative industrial hydraulic circuits.
Chapter 6 Quality Assurance and Global Distribution
HANJIU Technology operates a fully integrated manufacturing facility in Shijiazhuang featuring precision CNC machining centers, automated gerotor set production lines, and comprehensive testing and validation equipment. The quality management system is certified to ISO 9001:2015 standards, with additional CE marking compliance for all products supplied to European markets.
● 100% pressure testing: every OMR motor undergoes hydrostatic pressure testing at 1.5 times maximum rated working pressure to verify housing integrity and seal performance
● Performance validation: output speed, torque, and volumetric efficiency are measured and recorded for each production unit against specification tolerances
● Dimensional verification: precision measurement using CMM and conventional metrology ensures interchangeability with Danfoss and other OEM specifications
● Material traceability: nodular cast iron housings, alloy steel shafts, and gerotor sets sourced from qualified suppliers with full lot traceability
● Warranty coverage: 12-month warranty against defects in materials and workmanship under normal operating conditions
The global distribution network encompasses authorized dealers, OEM direct accounts, and aftermarket distributors in more than 80 countries. Regional warehouse stocking in Europe, North America, Southeast Asia, and the Middle East ensures delivery times of 1 to 7 days for standard orders. HANJIU's export volume has grown consistently at double-digit annual rates, reflecting the confidence of international customers in the company's commitment to quality, competitive pricing, and responsive customer service.
Chapter 7 Ordering Guide and Technical Support
7.1 Selection Procedure
Specifying the correct HANJIU OMR orbital motor for a given application follows a systematic procedure that considers torque requirements, system pressure, flow availability, and installation constraints:
● Step 1: Calculate required output torque including application service factor (typically 1.25 to 1.5 for construction and agricultural equipment)
● Step 2: Determine available system working pressure and confirm motor pressure rating adequacy (continuous vs intermittent duty)
● Step 3: Calculate required flow rate based on desired output speed and selected displacement: Q = Vg x n / 1000 (L/min)
● Step 4: Verify that calculated speed, flow, and pressure all fall within the motor's continuous duty envelope
● Step 5: Select mounting flange (A2 oval or C square), shaft type (cylindrical, splined, or tapered), and port configuration to match installation requirements
● Step 6: Specify shaft seal type (standard or high-pressure HPS) based on expected return line back pressure
7.2 Technical Support and Customer Service
HANJIU Technology provides comprehensive technical support through multiple channels designed to ensure successful product selection, installation, and ongoing maintenance. Direct telephone consultation is available during extended business hours (China Standard Time). Email technical inquiries receive guaranteed response within 2 hours during business hours. Complete technical documentation including datasheets, installation manuals, troubleshooting guides, and function diagrams is available for download. Video technical support and remote diagnostic assistance is provided for complex application challenges. On-site field service support is available for major OEM accounts and distribution partners.
The technical support team comprises qualified hydraulic engineers with extensive practical experience across construction machinery, agricultural equipment, industrial automation, and mobile hydraulics applications. Whether the requirement involves new equipment design, system troubleshooting, or maintenance optimization, HANJIU's engineering team delivers actionable solutions that maximize equipment productivity and minimize total cost of ownership.
Conclusion
The HANJIU OMR series medium-duty orbital hydraulic motor represents a proven, cost-optimized solution for applications requiring higher torque capacity and greater bearing durability than light-duty alternatives can provide. With ten displacement models delivering continuous torque from 65 Nm to 580 Nm, pressure ratings to 175 bar continuous (200 bar intermittent), and complete dimensional interchangeability with the Danfoss OMR series, HANJIU addresses the full spectrum of medium-duty hydraulic power transmission requirements.
The roller gear ring mechanism, robust bearing configuration, and versatile mounting options position the OMR series as the motor of choice for construction machinery, agricultural equipment, forestry operations, material handling systems, and industrial automation. Combined with extensive spare parts availability, competitive lifecycle costs, and responsive global technical support, HANJIU OMR orbital motors deliver tangible value that strengthens the competitive position of OEM manufacturers and reduces operating costs for end-user equipment fleets. As hydraulic technology evolves toward higher efficiency and smarter integration, HANJIU remains committed to advancing its OMR product line through continuous engineering investment and manufacturing excellence.
References
[1] Danfoss Power Solutions. Orbital Motors Type OMP X and OMR X Technical Information. 2018.
[2] Danfoss Power Solutions. OMP, OMR and OMH Orbital Motors Technical Information [151-1013]. 2011.
[3] Danfoss Power Solutions. OMR X Technical Data and Function Diagrams [151-1386, 151-1753]. 2023.
[4] Danfoss Power Solutions. OMR Dimensions, European and US Versions [151-1844, 151-1849]. 2023.
[5] Shijiazhuang Hanjiu Technology Co., Ltd. HANJIU OMR Series Orbital Motor Product Catalog. 2024.
[6] Shijiazhuang Hanjiu Technology Co., Ltd. Model Cross Reference Guide: HANJIU OMR vs Danfoss, Eaton, M+S. 2024.
[7] ISO 9001:2015. Quality Management Systems - Requirements. International Organization for Standardization.
[8] Directive 2006/42/EC. Machinery Directive. European Parliament and Council.
HANJIU TECHNOLOGY
Your Trusted Partner for Hydraulic Power Solutions
© 2025 Shijiazhuang Hanjiu Technology Co., Ltd. All Rights Reserved.