Product Overview
The MKD04-2-114-K04-3340-37MZ is a dual-displacement compact radial piston hydraulic motor from Poclain Hydraulics’ MKD04 series, part of the MK compact motor family. The manufacturer part number is A02172L and the approximate weight is 31.0 kg.
The MK/MKD series is Poclain’s ultra-compact direct-drive motor line engineered for space-constrained applications, featuring an ultra-short axial design and large diameter 4-contact roller bearing. The range covers displacements from 272 to 2812 cc/rev with up to 400 bar maximum pressure and 160 rpm maximum speed. The MKD04 frame size delivers maximum displacement of 545 cc/rev, maximum torque of 3470 N·m, maximum power of 18 kW (24 HP) and maximum speed of 90 rpm. Designed specifically for road rollers, the MKD04 series also serves mining, agricultural, environmental and other markets.
The model code breaks down as follows: MKD04 identifies the MK series 04 frame size with brake (D = with brake); 2 denotes displacement group 2 (545 cc/rev); 114 is the flow-distribution/function module code; K04 is the mounting flange and shaft configuration code; 3340 is the output module and mounting dimension code; 37MZ denotes additional options including port orientation, shaft seal type and brake configuration.
Every unit undergoes 100% simulated operating-condition bench testing prior to shipment. Mounting flange, shaft end and port dimensions match the original Poclain MKD04 series exactly, enabling true drop-in interchangeability with zero modification required.
Technical Specifications
MK04/MKD04 Series Frame Size Specifications:
MK04 Displacement Group 8: Displacement 272 cc/rev (16.6 cu.in/rev), theoretical torque at 100 bar 432 N·m, max power 18 kW (24 HP), max speed 120 rpm, max pressure 400 bar (5,802 PSI)
MK04 Displacement Group 0: Displacement 340 cc/rev (20.7 cu.in/rev), theoretical torque at 100 bar 541 N·m, max power 18 kW (24 HP), max speed 110 rpm, max pressure 400 bar (5,802 PSI)
MK04 Displacement Group 2: Displacement 408 cc/rev (24.9 cu.in/rev), theoretical torque at 100 bar 649 N·m, max power 18 kW (24 HP), max speed 100 rpm, max pressure 400 bar (5,802 PSI)
MKD04 Displacement Group 0: Displacement 456 cc/rev (27.8 cu.in/rev), theoretical torque at 100 bar 725 N·m (369 lb.ft), max power 18 kW (24 HP), max speed 90 rpm, max pressure 400 bar (5,800 PSI)
MKD04 Displacement Group 1: Displacement 502 cc/rev (30.6 cu.in/rev), theoretical torque at 100 bar 798 N·m (406 lb.ft), max power 18 kW (24 HP), max speed 82 rpm, max pressure 400 bar (5,800 PSI)
MKD04 Displacement Group 2 (This Model): Displacement 545 cc/rev (33.2 cu.in/rev), theoretical torque at 100 bar 867 N·m (441 lb.ft), max power 18 kW (24 HP), max speed 75 rpm, max pressure 400 bar (5,800 PSI)
MK04/MKD04 Series Common Specifications:
Series Max Displacement: 545 cc/rev (33.2 cu.in/rev)
Series Max Torque: 3,470 N·m (2,559 lb-ft)
Series Max Pressure: 400 bar (5,802 PSI)
Rated Pressure: 350 bar (4,900 PSI)
Series Max Power: 18 kW (24 HP)
Series Max Speed: 90 rpm (MKD04) / 120 rpm (MK04)
Type: Radial piston LSHT hydraulic motor (internal curve cam ring design)
Bearing Type: Large diameter 4-contact roller bearing
Control: Single or dual displacement
Brake: Parking brake (D version integrated)
Motor Type: Wheel motor / shaft motor
Motor Inertia: 0.028 kg·m²
Original Design: Poclain Hydraulics, France
MKD04-2-114-K04-3340-37MZ Additional Specifications:
Model Code: MKD04-2-114-K04-3340-37MZ
Manufacturer Part Number: A02172L
Type: Ultra-compact radial piston motor, internal curve design, integrated parking brake
Displacement: 545 cc/rev (33.2 cu.in/rev)
Theoretical Torque at 100 bar: 867 N·m (441 lb.ft)
Max Torque: 3,470 N·m (2,559 lb-ft)
Max Working Pressure: 400 bar (5,802 PSI)
Rated Working Pressure: 350 bar (4,900 PSI)
Max Power: 18 kW (24 HP)
Max Speed: 75 rpm (at max displacement)
Parking Brake Torque: 3,170 N·m (2,338 lb-ft, with 0 bar in housing, new brake)
Brake Min. Release Pressure: 17 bar (246.6 PSI)
Brake Max. Release Pressure: 30 bar (435.1 PSI)
Mounting Flange: Ø204.9 mm chassis mounting, 7×M12×1.75 screws
Tightening Torque: 12.9 N·m (145 lb.ft)
Mounting Surface Flatness: 0.2 mm (0.01 in)
Surface Roughness: Ra 12.5 μm (0.49 μin)
Motor Inertia: 0.028 kg·m²
Weight: ~31.0 kg
Hydraulic Fluid: HV46 recommended
Operating Temperature Range: -40°C to +115°C
Original Design: Poclain Hydraulics, France
Key Technical Advantages
1. Low Noise Internal Curve Radial Piston Design for Quiet and Smooth Operation
The MKD04-2-114 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. The design features significantly low noise characteristics—MS/MSE/MK radial piston high-torque cam motors are renowned for high pressure, high efficiency and very little noise output. With theoretical torque of 867 N·m at 100 bar and maximum torque of 3,470 N·m at full displacement, the motor operates smoothly across the 0–75 rpm speed range without stick-slip.
2. Ultra-Compact Direct Drive Design with Large Diameter 4-Contact Roller Bearing
The MKD04-2-114 features Poclain MK series’ signature ultra-short axial design with a large diameter 4-contact roller bearing capable of directly handling wheel and vibration shaft radial loads without additional bearing support. This makes it an ideal choice for road roller vibration shaft coaxial drives. The MK series features ultra-short motor design and large diameter 4-contact roller bearing, developed specifically for compactor drive applications. Designed specifically for road rollers, also serving mining, agricultural, environmental and other markets.
3. Integrated Parking Brake (D Version) for Safe Parking
This model is the MKD04 brake version (D = with brake), integrating a parking brake module with a hydraulically released, spring-applied fail-safe design. Parking brake torque is 3,170 N·m (2,338 lb-ft) with a minimum release pressure of 17 bar and maximum release pressure of 30 bar. The brake automatically locks when system pressure is lost, ensuring safe machine parking. This makes the MKD04-2-114 particularly suitable for road rollers and construction vehicles requiring reliable parking brakes.
4. Modular Architecture and High Radial Load Capacity
The MK/MKD series employs Poclain’s modular design concept, allowing displacement group, flow-distribution module, brake module and output-end module to be reconfigured. The K04 mounting configuration supports both wheel-drive and shaft-output mounting. The large diameter 4-contact roller bearing directly handles wheel and vibration shaft radial loads without additional bearing support mechanisms, simplifying drivetrain design. The modular design allows replacement of individual worn modules rather than the entire motor.
5. 100% Simulated Load Testing & Drop-In Interchangeability
Each MKD04-2-114-K04-3340-37MZ unit is bench-tested under simulated operating conditions prior to dispatch, covering pressure cycling, speed shifting, brake performance and thermal variation. Mounting flange, shaft end and port dimensions match the original Poclain MKD04 series exactly, enabling direct replacement without pipework or interface modification. Motor total efficiency averages are excellent at 50°C using HV46 hydraulic oil after 100 hours of operation, with starting torque calculated at 85% of initial torque at given pressure.
Application Areas
The MKD04 series is designed specifically for road rollers and is also widely deployed across the following:
Road Rollers: double drum asphalt roller vibration shaft coaxial drives, single drum roller wheel drives, including Bomag, HAMM and similar brands (Poclain is the market benchmark for double drum roller hydrostatic transmission)
Construction: compact excavator travel drives, skid steer loaders, road maintenance machinery
Mining: subsurface equipment drives, mining truck auxiliary drives
Agriculture: tractor front axles, harvester drive systems
Material Handling: forklifts, aerial work platforms
Environmental Equipment: street sweepers, municipal vehicles
Industrial: winches, conveyor drives
Expert Maintenance Tips
1. Brake Running-In and Release Pressure Verification: The MKD04-2-114 features an integrated parking brake with 3,170 N·m (2,338 lb-ft) braking torque, minimum release pressure of 17 bar (246.6 PSI) and maximum release pressure of 30 bar (435.1 PSI). Running-in is required after installation. Abnormally high release pressure typically indicates friction plate wear or piston seal failure—replace promptly. During reassembly, coat the piston seal contact surface with anti-oxidizing grease.
2. Chassis Mounting Surface Inspection: The MKD04-2-114-K04 features Ø204.9 mm chassis mounting with 7×M12×1.75 screws at 12.9 N·m (145 lb.ft) tightening torque. Mounting surface flatness requirement is 0.2 mm with Ra 12.5 μm surface roughness. Ensure flange mating surface parallelism deviation does not exceed 0.05 mm during installation, and tighten bolts evenly in a diagonal sequence. Periodically inspect the output flange plane and wheel/vibration shaft mating surface for wear or deformation.
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 brake friction plate and seal degradation. Replace hydraulic oil and filter after the first 500 hours, then follow a 2,000-hour or annual replacement cycle. 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 MKD04-2-114’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. 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 MK/MKD 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, cam rings and brake friction plates to minimize machine downtime. When replacing modules, follow Poclain official technical manual torque values and assembly sequences.
