SK200-8 Swing Gearbox Reducer Compatible with Komatsu PC200-8 PC220-8 CE Certified

Core Structure

• Sun gear: Connects to the slewing motor via splines to receive high-speed power.
• Planet gear: 3–4 units per stage, adopting planetary motion to transfer torque efficiently.
• Ring gear: Fixed on the housing and meshes accurately with planet gears.
• Planet carrier: Outputs power to drive the bottom pinion gear.
• Brake: Integrated wet multi-disc brake; spring braking and hydraulic release for safe positioning.
• Housing & Bearing: High-strength steel housing matched with heavy-duty bearings, with good dustproof and sealing performance.

• Working Principle

  The hydraulic motor outputs high-speed low-torque power, which is decelerated and torque-boosted by two-stage planetary gears. The low-speed high-torque pinion meshes with the slewing bearing inner gear ring, driving the upper structure to rotate smoothly.

  Common Faults and Causes

  • Abnormal noise & jitter: Gear pitting and wear, bearing failure, poor oil quality, improper meshing clearance.
  • Oil leakage: Aging seals, housing cracks, overfilled oil, clogged breather valve.
  • Slow & weak slewing: Worn gears/bearings, brake dragging, motor internal leakage, unmatched speed ratio.
  • Overheating: Insufficient or degraded oil, overload, persistent brake friction, weak heat dissipation.
  • Gear jumping & tooth breakage: Shock load, internal foreign matter, fatigue wear, assembly misalignment.