SK350-8 Excavator Swing Motor Gearbox Reducer Slewing Drive Reduction Excavator Machinery Parts
SK350-8 Excavator Swing Motor Gearbox Reducer Slewing Drive Reduction Excavator Machinery Parts
The excavator swing reducer, generally referred to as the swing gearbox, is an essential transmission assembly that links the swing motor with the large slewing gear ring. It is mainly designed for speed reduction and torque boost, enabling the upper carriage to achieve smooth 360-degree rotation.
Core Structure
• Sun gear: Splined to the slewing motor to input high-speed power.
• Planet gear: 3 to 4 pieces per stage, rotates both revolutionally around the sun gear and rotationally on its own axis to transmit torque.
• Ring gear: Fixed to the housing and meshes with the planet gears.
• Planet carrier: Outputs power and drives the lower pinion (drive gear).
• Brake: Built-in wet multi-disc brake; spring-applied braking and hydraulic release to prevent slewing runaway.
• Housing and bearing: High-strength cast steel / forged steel housing, supported by heavy-duty bearings, with dustproof and leakproof performance.
Working Principle
Abnormal noise / Stuttering: Gear wear / pitting corrosion, bearing damage, insufficient oil / dirty oil, abnormal meshing clearance.
Oil leakage: Oil seal aging, housing cracks, excessive oil level, breather valve blockage.
Weak slewing / Slow slewing: Gear / bearing wear, brake failure to release, motor internal leakage, mismatched speed ratio.
Overheating: Insufficient oil / oil deterioration, overload, brake dragging, poor heat dissipation.
Gear jumping / Broken gear teeth: Impact load, foreign matter entry, fatigue wear, installation misalignment.
| Machinery Test Report | Provided | Warranty | 1 Year |
| Video outgoing-inspection | Provided | Brand Name | OEM |
| Place of Origin | China | Part Name | Swing Reduction Assembly |
| Model | SK350-8 | Keyword | Swing Gearbox |
| MOQ | 1 Piece | Quality | Tested Great Performance |
| Application | Excavator | Delivery Time | 7-35 Days |
| Service | Professsional Service | Condition | Brand New |

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