Product Overview
The ME350BP is a mid-frame axial piston low-speed high-torque motor from Eaton Vickers’ DOWMAX ME series, featuring a displacement of 350 cm³/rev (21.36 in³/rev), rated working pressure of 276 bar (4,000 psi), peak pressure of 324 bar (4,700 psi), rated speed of 600 rpm and maximum speed of 800 rpm. The DOWMAX ME series employs a unique double swash plate axial piston design, delivering highest performance in the low-speed range with smooth rotation at speeds down to 1 rev/min.
The model code breaks down as follows: ME identifies the DOWMAX ME series axial piston motor; 350 denotes the 350 cm³/rev displacement; B indicates the 3rd design change; P denotes the JIS spline shaft. The corresponding Eaton part number is 1230011.
The DOWMAX ME series covers 13 displacement sizes from 99 to 4,097 cm³/rev, providing broad application coverage. The series offers high starting torque, high overall efficiency, compact construction and quiet operation, unaffected by thermal shock and suitable for cold-temperature starting. The ME350BP is widely deployed in ship cranes, port equipment, large track travel drives, stacker-reclaimers and metallurgical equipment.
Every ME350BP unit undergoes 100% simulated operating-condition bench testing prior to shipment. Mounting flange, shaft end and port dimensions match the original Eaton Vickers ME350BP exactly, ensuring true drop-in interchangeability with zero modification required.
Technical Specifications
DOWMAX ME Series Frame Size Specifications:
ME100: Displacement 99 cm³/rev (6.04 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 434 N·m (320 lb-ft), rated speed 1000 rpm, max speed 1000 rpm, max power 61 hp, weight 18.28 kg (49 lbs)
ME150: Displacement 152 cm³/rev (9.27 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 668 N·m (492 lb-ft), rated speed 600 rpm, max speed 800 rpm, max power 56 hp, weight 34.3 kg (92 lbs)
ME175: Displacement 175 cm³/rev (10.68 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 769 N·m (566 lb-ft), rated speed 600 rpm, max speed 800 rpm, max power 65 hp, weight 34.3 kg (92 lbs)
ME300B: Displacement 304 cm³/rev (18.55 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 1,334 N·m (984 lb-ft), rated speed 600 rpm, max speed 800 rpm, max power 112 hp, weight 43.6 kg (117 lbs)
ME350B (This Model): Displacement 350 cm³/rev (21.36 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 1,536 N·m (1,133 lb-ft), rated speed 600 rpm, max speed 800 rpm, max power 129 hp, weight 43.6 kg (117 lbs)
ME600A: Displacement 602 cm³/rev (36.74 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 2,641 N·m (1,948 lb-ft), rated speed 450 rpm, max speed 600 rpm, max power 167 hp, weight 75.8 kg (203 lbs)
ME750A: Displacement 750 cm³/rev (45.76 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 3,289 N·m (2,426 lb-ft), rated speed 400 rpm, max speed 520 rpm, max power 185 hp, weight 98.9 kg (265 lbs)
ME850: Displacement 847 cm³/rev (51.68 in³/rev), rated pressure 276 bar (4,000 psi), peak pressure 324 bar (4,700 psi), rated torque 3,715 N·m (2,740 lb-ft), rated speed 350 rpm, max speed 450 rpm, max power 183 hp, weight 98.9 kg (265 lbs)
ME1300A: Displacement 1,345 cm³/rev (82.06 in³/rev), rated pressure 248 bar (3,600 psi), peak pressure 324 bar (4,700 psi), rated torque 5,309 N·m (3,916 lb-ft), rated speed 200 rpm, max speed 390 rpm, max power 186 hp, weight 140 kg (375 lbs)
ME1900: Displacement 1,868 cm³/rev (113.97 in³/rev), rated pressure 248 bar (3,600 psi), peak pressure 324 bar (4,700 psi), rated torque 7,373 N·m (5,438 lb-ft), rated speed 140 rpm, max speed 260 rpm, max power 173 hp, weight 222 kg (595 lbs)
ME350BP Additional Specifications:
Model Code: ME350BP
Eaton Part Number: 1230011
Type: Axial piston motor, double swash plate design
Displacement: 350 cm³/rev (21.36 in³/rev)
Rated Working Pressure: 276 bar (4,000 psi)
Peak Pressure (Intermittent): 324 bar (4,700 psi)
Rated Torque: 1,536 N·m (1,133 lb-ft)
Rated Speed: 600 rpm
Max Speed: 800 rpm
Min Smooth Speed: 1 rev/min
Max Horse Power: 129 hp
Rotation: Clockwise
Shaft Type: JIS spline shaft (P code)
Seal Material: Nitrile rubber (NBR)
Port Type: Standard ports (B code special ports for counterbalance valves)
Design Generation: B (3rd design)
Weight: ~43.6 kg (117 lbs)
Thermal Shock: Unaffected, suitable for cold-temperature starting
Key Technical Advantages
1. Double Swash Plate Axial Piston Design for High Startup Torque and Low-Speed Smoothness
The ME350BP employs Eaton DOWMAX’s signature double swash plate axial piston design. The combination of multiple pistons and double swash plates enables smooth rotation at speeds down to 1 rev/min. This makes it irreplaceable in ship cranes, port machinery and large track travel drives requiring extremely low-speed high-torque output. High startup torque ensures reliable starting under load.
2. High Pressure Capability — 276 Bar Rated
The ME350BP supports 276 bar rated working pressure and 324 bar peak pressure, with rated torque of 1,536 N·m (1,133 lb-ft) and maximum power of 129 hp. This torque density enables direct driving of heavy loads without additional reduction gearing, simplifying drivetrain design.
3. Unaffected by Thermal Shock and Wide Temperature Adaptability
DOWMAX ME series motors are unaffected by thermal shock and start reliably in cold environments. This makes them particularly suitable for outdoor operations, ship deck equipment and industrial environments with large temperature variations. Nitrile rubber seals are standard, with Viton seals optional for phosphate ester fluid systems.
4. Compact Construction, Quiet Operation and High Overall Efficiency
The ME350BP features a compact, easy-to-install and robust construction weighing only about 43.6 kg. The multi-piston and double swash plate design effectively reduces operating noise and torque pulsation for quiet operation. High overall efficiency delivers excellent energy performance under long-term continuous loading.
5. 100% Simulated Load Testing & Drop-In Interchangeability
Each ME350BP unit is bench-tested under simulated operating conditions prior to dispatch, covering pressure cycling, speed stepping and thermal shock. Mounting flange, shaft end and port dimensions match the original Eaton Vickers ME350BP exactly, enabling direct replacement without pipework or interface modification.
Application Areas
The ME350BP is deployed across demanding heavy industrial applications:
Ship & Port Equipment: ship cranes, deck machinery, port cranes, anchor winch drives
Large Track Travel Drives: crawler crane travel drives, large excavator track drives
Stacker-Reclaimers: bucket wheel drives, slewing drives
Metallurgical Equipment: continuous casting machines, rolling mill auxiliary drives
Mining: heavy mining equipment drives
Industrial: large coilers, industrial conveying systems
Specialty Vehicles: road sweepers, rotary drilling rigs
Expert Maintenance Tips
1. Oil Cleanliness and Temperature Control: Maintain system oil cleanliness at ISO 4406 18/16/13 or better. 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.
2. Drain Line Management: 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. After extended shutdown, fill the housing with clean hydraulic oil before restarting.
3. Splined Shaft and Coupling Inspection: The ME350BP is configured with a JIS spline shaft (P code). Periodically inspect output spline shaft wear; excessive spline clearance causes abnormal vibration and noise. Coupling alignment deviation must not exceed 0.05 mm to prevent abnormal bearing wear and shaft seal leakage.
4. Periodic Piston Group and Swash Plate Inspection: Inspect piston-to-cylinder bore clearance, slipper wear and swash plate working surface every 2,000 hours. Abnormal efficiency loss or noise requires immediate shutdown and service. Use original specification parts when replacing piston groups to ensure fit accuracy.
5. Cold Environment Starting Precautions: Although the ME350BP is unaffected by thermal shock, when starting in cold environments, run at low speed for warm-up before applying load. Use hydraulic fluid with appropriate low-temperature performance to ensure oil viscosity remains within the permissible range during startup.
