Product Overview
The MS35-2-1B9-A35-2A50 is a large-frame dual-displacement radial piston hydraulic motor from Poclain Hydraulics’ MS35 series, belonging to displacement group 2 with a two-speed (2-displacement) concept and 2A50 wheel flange mounting configuration. The MS35 series is the large frame offering in Poclain’s MS multipurpose motor line, covering displacements from 2439 to 4198 cc/rev with up to 110 kW (148 HP) power, 30,000 N·m (22,126 lb-ft) maximum torque and 450 bar (6,527 psi) maximum working pressure, with a multi-speed concept reaching up to 140 rpm.
The MS35 series is built on a tried and tested radial piston cam design that is continually being improved, delivering high efficiency at any speed or operating pressure and making a major contribution to machine energy efficiency. Optimized through thousands of hours of development and testing, MS series motors withstand the most extreme operating conditions while requiring very little maintenance, reducing machine downtime and optimizing productivity. The series employs a modular design concept allowing a single base motor to be configured with different displacement groups, flow-distribution modules, brake modules and output-end modules, serving construction equipment, material handling, agriculture, environment, mining, rail, marine and industry.
The model code breaks down as follows: MS35 identifies the MS series 35 frame size; 2 denotes displacement group 2 (4198/2099 ml/r dual displacement); 1B9 is the flow-distribution/function module code; A35 is the shaft and mounting configuration code; 2A50 is the wheel flange mounting and output-end code.
Every MS35-2-1B9-A35-2A50 unit undergoes 100% simulated operating-condition bench testing prior to shipment, covering pressure cycling, speed shifting and volumetric efficiency verification. Mounting flange, shaft end and port dimensions match the original Poclain MS35 series exactly, enabling true drop-in interchangeability with zero modification required.
Technical Specifications
MS35 Series Frame Size Specifications:
MS35-8: Full displacement 2439 ml/r (148.8 cu.in/rev), half displacement 1220 ml/r (74.4 cu.in/rev)
MS35-9: Full displacement 3143 ml/r (191.8 cu.in/rev), half displacement 1572 ml/r (95.9 cu.in/rev)
MS35-0: Full displacement 3494 ml/r (213.2 cu.in/rev), half displacement 1747 ml/r (106.6 cu.in/rev), rated speed 130 rpm, max pressure 450 bar
MS35-1: Full displacement 3836 ml/r (234.1 cu.in/rev), half displacement 1918 ml/r (117.0 cu.in/rev)
MS35-2 (This Model): Full displacement 4198 ml/r (256 cu.in/rev), half displacement 2099 ml/r (128.1 cu.in/rev), max torque 30000 N·m (22126 lb-ft), max pressure 450 bar (6527 PSI), max power 110 kW (148 HP), max speed 110–140 rpm
MS35 Series Common Specifications:
Series Max Displacement: 4198 cc/rev (256 cu.in/rev)
Series Max Torque: 30,000 N·m (22,126 lb-ft)
Series Max Pressure: 450 bar (6,527 psi)
Series Rated Pressure: 400 bar (5,000 psi)
Series Max Power: 110 kW (148 HP)
Series Max Speed: 140 rpm
Type: Radial piston LSHT hydraulic motor (internal curve cam ring design)
Control: Single or dual displacement (multi-speed concept)
Brake: Service brake, parking brake and hydrostatic boosted brake options
Motor Type: Wheel motor / shaft motor (modular)
Anti-Skid Option: TwinLock™ integrated anti-skid available
Displacement Range: 2439–4198 cc/rev
Original Design: Poclain Hydraulics, France
MS35-2-1B9-A35-2A50 Additional Specifications:
Model Code: MS35-2-1B9-A35-2A50
Type: Radial piston LSHT hydraulic motor, internal curve cam ring design
Displacement: 4198 ml/r (256 cu.in/rev) full / 2099 ml/r (128.1 cu.in/rev) half
Displacement Ratio: 2:1
Theoretical Torque at 10 MPa: 6,675 N·m
Max Torque: 30,000 N·m (22,126 lb-ft)
Rated Working Pressure: 400 bar (5,000 psi)
Max Working Pressure: 450 bar (6,527 psi)
Max Power: 110 kW (148 HP)
Max Speed: 110–140 rpm
Valving Type: Dual displacement valving module (1B9 code)
Mounting Flange: Wheel flange mounting (2A50 configuration)
Port Connections: ISO 6162 flanges & ISO 9974-1 connections
Anti-Skid Option: TwinLock™ available
Brake: Service brake, parking brake and hydrostatic boosted brake options
Motor Type: Wheel motor / shaft motor
Weight: ~185 kg (depending on configuration)
Operating Temperature Range: -40°C to +115°C
Hydraulic Fluid: Mineral oil (ISO VG46/68), synthetic oil, water glycol
Original Design: Poclain Hydraulics, France
Key Technical Advantages
1. Internal Curve Radial Piston Design for High Startup Torque and Smooth Low-Speed Operation
The MS35-2-1B9 employs Poclain’s patented internal curve radial piston design, with multiple pistons arranged radially around a cam ring to deliver high torque at extremely low speeds. With theoretical torque of 6,675 N·m at 10 MPa and maximum torque of 30,000 N·m at full displacement, the motor operates smoothly across the 0–140 rpm speed range without stick-slip. High startup torque ensures reliable starting under load, making it ideal for heavy-duty wheel-drive and tool drive applications.
2. Two-Speed Dual Displacement Design for Wide Operating Range
The MS35-2-1B9 features a dual-displacement cam ring design with on-line switching between 4198 ml/r full displacement and 2099 ml/r half displacement for a 2:1 ratio. The full-displacement mode delivers maximum torque for heavy-duty startup and grade climbing; the half-displacement mode significantly increases speed capability for light-load cruising. A single motor covers the full spectrum from low-speed high-torque to high-speed low-torque operation. The multi-speed concept enables efficient operation at speeds up to 140 rpm.
3. Modular Architecture with TwinLock™ Anti-Skid System
The MS35 series employs Poclain’s modular design concept, allowing displacement group, flow-distribution module, brake module and output-end module to be reconfigured. The modular design facilitates use in demanding applications across construction equipment, material handling, agriculture, environment, mining, rail, marine and industry. The 2A50 wheel flange mounting configuration supports wheel-drive mounting. Optional TwinLock™ integrated anti-skid provides differential locking via hydraulic control for improved traction. Brake options include service brake, parking brake and hydrostatic boosted brake modules.
4. High-Precision Cam Ring and High Radial Load Capacity
The MS35-2-1B9 cam ring is manufactured from high-hardness alloy steel (60–62 HRC) with precision grinding to resist high-frequency contact fatigue from piston rollers. A hydrodynamic oil film forms between rollers and cam ring, significantly reducing wear rate and extending overhaul intervals. The motor features large diameter bearing support, enabling direct handling of wheel or tool-end radial loads without additional bearing support mechanisms, simplifying drivetrain design. The modular design allows replacement of individual worn modules rather than the entire motor, substantially reducing total cost of ownership.
5. 100% Simulated Load Testing & Drop-In Interchangeability
Each MS35-2-1B9-A35-2A50 unit is bench-tested under simulated operating conditions prior to dispatch, covering pressure cycling, speed shifting and thermal variation. Mounting flange, shaft end and port dimensions match the original Poclain MS35 series exactly, enabling direct replacement without pipework or interface modification. Both complete motors and spare parts are 100% interchangeable.
Application Areas
The MS35 series is widely deployed in heavy-duty travel and tool drives:
Construction: large wheel loaders (Caterpillar 980H/988K, Volvo L220H/L260H, Komatsu WA600/WA700), large excavator travel drives
Road Rollers: large vibratory roller wheel drives and vibration shaft drives
Agriculture: large tractors (John Deere 9570RX/9620RX, Case IH Steiger 540/620)
Self-Propelled Sprayers: Agrifac Condor Endurance, Amazone Pantera 7004, Hardi Alpha 5100
Mining: subsurface loaders, mining truck auxiliary drives, heavy-duty handling cars
Marine & Offshore: deck machinery, winch drives, thruster drives
Industrial: large shredders, industrial conveyors, mill drives
Rail: track maintenance vehicle drives
Expert Maintenance Tips
1. Dual Displacement Valving Module Maintenance: The 1B9 dual displacement valving module is controlled by pilot pressure. If shift response is sluggish or excessively harsh, inspect the pilot control spool for sticking and the flow-distribution shaft O-rings for aging. Shift operations should be performed at low speed or standstill to avoid impact loading on the distribution mechanism. Inspect pilot control pressure and valving module seal condition every 1,000 hours.
2. Wheel Flange Mounting Surface Inspection: The MS35-2-1B9-A35-2A50 features 2A50 wheel flange mounting. Periodically inspect the output flange plane and wheel hub mating surface for wear or deformation. Ensure flange mating surface parallelism deviation does not exceed 0.05 mm during installation, and tighten bolts evenly in a diagonal sequence to Poclain technical manual torque values. Mounting surface flatness requirement is 0.2 mm with Ra 12.5 μm surface roughness.
3. Oil Cleanliness and Temperature Control: Maintain system oil cleanliness at ISO 4406 18/16/13 or better. HV46 hydraulic oil is recommended. Operating oil temperature should be kept below 80°C; elevated temperatures accelerate seal degradation. Replace hydraulic oil and filter after the first 500 hours, then follow a 2,000-hour or annual replacement cycle. Case drain temperature is affected by pressure and speed and is always higher than circuit temperature—system temperature must not exceed 115°C at any point.
4. Drain Line Management and Housing Priming: The drain port must return to the reservoir independently—housing back pressure must not exceed 2 bar. The drain line end must remain submerged to prevent air ingestion. Fill the housing with clean hydraulic oil before first startup. After extended shutdown, fill the housing again before restarting.
5. Periodic Piston Group and Cam Ring Inspection: As a radial piston motor, the MS35-2-1B9’s primary wear points are the piston rollers and cam ring contact surface. Inspect piston roller wear and cam ring working surface every 2,000 hours. Both displacement cam surfaces require inspection. Abnormal noise or efficiency loss requires immediate shutdown and service. Use Poclain original specification parts when replacing piston groups to ensure fit accuracy and assembly torque per technical manual requirements.
6. Modular Repair Strategy: The MS35 series modular design allows replacement of individual worn modules rather than the entire motor. Establish a modular spare parts inventory including flow-distribution module seals, piston groups and cam rings to minimize machine downtime. When replacing modules, follow Poclain official technical manual torque values and assembly sequences.
