High Torque Swing Motor Gearbox EC350 Excavator Final Drives Excavator Machinery Parts

Core Structure

• Sun gear: Splined connection for power input from the slewing motor at high speed.
• Planet gear: 3 to 4 units each stage; dual motion of revolution and rotation for torque transmission.
• Ring gear: Fixed onto reducer housing and engaged with planet gears all the time.
• Planet carrier: Serves as final power output to drive the lower pinion gear.
• Brake: Built-in wet multi-disc brake assembly; spring holds brake engaged, hydraulic pressure releases it to avoid slewing sliding.
• Housing & Bearing: High-strength steel housing by casting or forging, heavy-duty bearing arrangement, reliable dust and oil sealing.

Working Principle

Common Faults & Causes

• Abnormal noise and jerking: Gear surface pitting and wear, bearing damage, insufficient lubrication, dirty gear oil, irregular meshing clearance.
• Lubricant leaking: Aging sealing elements, housing cracks, excessive oil filling, blocked air vent valve.
• Slow slewing and weak power: Gear or bearing wear failure, incomplete brake disengagement, motor internal leakage, inappropriate speed ratio selection.
• Over temperature fault: Oil level shortage, oil performance deterioration, overload operation status, brake dragging friction, poor heat emission.
• Gear jump and tooth fracture: Dynamic impact load, foreign matter entering gearbox, long-term fatigue abrasion, installation misalignment error.