SY135 Excavator Swing Gearbox OEM Reduction Drive Swing Final Drive

Core Structure

• Sun Gear: Precise spline connection with slewing motor to input high-speed rotary power.
• Planet Gear: 3–4 gears per stage with combined revolving and rotating movement to transfer torque steadily.
• Ring Gear: Firmly fixed on reducer housing to keep accurate meshing with planet gears.
• Planet Carrier: Reliable power output unit to drive the bottom drive pinion gear.
• Brake System: Advanced built-in wet multi-disc brake; spring locking and hydraulic releasing avoid accidental slewing.
• Housing & Bearing: Heavy-duty cast/forged steel housing matched with high-load bearings, excellent dust-proof and oil-sealing effect.

Working Principle

Common Faults & Causes

• Unusual noise and unstable operation: Gear wear & pitting, bearing failure, insufficient or contaminated lubricant, unreasonable meshing gap.
• Gear oil leakage problem: Aging oil seals, housing cracks, excessive oil level, clogged ventilation valve.
• Slewing weakness and slow movement: Gear/bearing abrasion, brake release failure, motor internal leakage, improper gear ratio matching.
• High temperature overheating: Oil lack or aging, overload working, brake continuous dragging, poor heat dissipation performance.
• Gear skipping and tooth damage: External impact load, internal foreign dust, long-term fatigue wear, assembly position deviation.