Poclain MK & MSE Series Hydraulic Motor | MK18 MK35 MSE18 Radial Piston Motor

The MK and MSE Series heavy-duty radial piston motors manufactured by Chengyuan Hydraulic are low-speed high-torque (LSHT) fluid power operators engineered to be completely compatible with Poclain industrial standards. Built upon the classic multi-stroke inward cam ring topology, these motors generate smooth torque delivery even under near-zero velocity matrices. This product suite directly manages high-tier customized applications including the heavy industrial MK18-1-D21-F12-1340-5800, the high-stiffness structural MK35-2-121-A18-1140-7000, and the mobile tracking MSE18-2-12A-R18-1120-5EJ0. Every single radial piston unit undergoes 100% simulated operational load testing for mechanical torque peaks, volumetric efficiency, and stall break-away characteristics under maximum pressure to match original performance specifications and offer proven 100% original-place interchangeability.

Technical Specifications :

• Core Product Framework: Poclain MK / MSE Series Multi-Stroke Radial Piston Hydraulic Motors

• Exact Model Configs Supported: MK18-1-D21-F12-1340-5800 / MK35-2-121-A18-1140-7000 / MSE18-2-12A-R18-1120-5EJ0

• Nominal Displacement Grid: * MK18 / MSE18 Frame Range: ~1000 $cm^3/rev$ to 2000 $cm^3/rev$ (strictly calibrated via 1340 & 1120 layout designators)

  • MK35 Frame Range: ~2500 $cm^3/rev$ to 4200 $cm^3/rev$ (calibrated via code multipliers or custom specs)

• Maximum Continuous Pressure: 40 MPa (400 bar / 5800 psi)

• Intermittent Peak Pressure Limit: 45 MPa (450 bar / 6525 psi)

• Maximum Continuous Torque Capacity: * MK18 / MSE18 Configurations: Rated up to 6000 – 9000 N·m continuous

  • MK35 Configurations: Heavy-capacity torque output up to 15000 – 22000 N·m continuous

• Operational Velocity Envelope: 0.5 rpm to 150 rpm (dependent on input delivery fluid metrics)

• Displacement Shift Configurations: Code 1/2 designates Single Displacement standard or Dual-Displacement pilot-switched control frameworks

• Mounting Shaft & Braking Layout: Codes D21/121 denote heavy wheel flanged bearings or standard male splines; suffix 5EJ0 specifies an integrated multi-disc wet hydraulic parking and emergency safety brake assembly

Key Technical Advantages:

• Perfect Hydrostatic Balance of Multi-Stroke Topology: The internal assembly consists of a multi-lobe cam ring ring guiding a radial cluster of pistons fitted with heavy rollers. Because opposing piston groups fire simultaneously across geometric axes, all axial and radial thrust loads acting on the rotor core are neutralized, lowering mechanical drag and driving mechanical efficiency up to 95%.

• Superior Anti-Cogging Metrology & Silent Run Blueprint: The continuous overlapping stroke sequence of the radial pistons cuts output flow ripples down to absolute minimums. Even at low speeds beneath 1 rpm, the motor exhibits zero “cogging” or speed stuttering. Removing high-speed gear reduction components allows the system to register noise values over 15 dB(A) quieter than comparable “high-speed motor + gearbox” configurations.

• Dual-Displacement Selective Dynamic Velocity Profiling: The indicator “2” within designations like MK35-2 and MSE18-2 represents a built-in directional-valve dual-displacement shift mechanism. When high-speed travel or low-load indexing is requested, external pilot pressure bypasses half of the piston cylinders, instantly doubling output shaft speed under constant system flow rates.

• Monoblock Wheel Mount Integration & Secure Wet Multi-Disc Braking: The MSE18-2 tracking propulsion motor features massive load-rated bearings directly inside the structural frame, meaning tires or track sprockets lock down directly to the hub. The integrated multi-disc wet brake assembly at the rear uses heavy mechanical spring force to apply braking and pilot line feed to release, checking all field safety parameters.

Application Areas:

• Heavy Mobile Traction Drives: Direct wheel traction systems for tracked excavators, anchoring drill carriages, agricultural machinery, and heavy industrial site transporters.

• Heavy Industrial Winch & Swivel Actuators: Main cable lift drums, marine anchor capstans, and heavy deck crane indexing systems.

• Sub-Surface Mining & Tunneling Rigs: Primary drive systems for heavy rock crushers, refuse shredding cylinders, and auxiliary rotation assemblies for tunnel boring setups.

Expert Maintenance Tips:

• Mandatory Case Flushing Circuit Protocol: Because radial piston groups carry complex frictional areas and high case fluid volumes, continuous high-pressure service will overheat internal bypass leakage. For systems operating under persistent full-load curves or dual-displacement high speeds, a dedicated case flushing line must be run (injecting cool system fluid at the lowest case port and routing out the highest case port directly back to the tank) to maintain case temperatures below 70°C.

• Pre-Lubrication Case Priming & Initial Venting Sequence: Before turning over a freshly installed or overhauled motor, you must pre-fill the casing through its highest drain port with 2 to 5 liters (depending on frame size) of ultra-clean anti-wear hydraulic fluid. Run the motor unloaded under low system pressure ($< 2 \text{ MPa}$) for 10 minutes to clear trapped air clusters.

• Strict Case Backpressure Redline Controls: Ensure the case drain run is plumbed completely independently back to the reservoir with near-zero resistance. The transient or continuous backpressure inside the motor shell must never exceed 0.5 MPa (5 bar). Necking down the drain lines or plumbing them into high-pressure return headers will instantly blow out the main high-pressure shaft seal lips.