3121153 XCMG GR2605 motor grader sun gear

Technical Parameters

• Model: 3121153
• Type: Planetary Transmission Sun Gear (Straight/Helical Teeth)
• Material: 20CrMnTi/20CrNiMo alloy forged steel, carburizing quenching + tempering
• Surface Treatment: Precision gear grinding, surface hardness HRC58-62, core hardness HRC30-40
• Accuracy Grade: GB/T 10095.1 Grade 6/7, meeting construction machinery transmission standards
• Number of Teeth: Standard series (matched with corresponding planet gear teeth)
• Module: Heavy-duty design for high torque transmission
• Structure: With internal spline/shaft hole, precisely matched with input shaft or planetary carrier
• Load Characteristics: High bending strength, contact fatigue strength, impact and overload resistance
• Operating Temperature: -40℃～120℃
• Functions: Power input for planetary gear train, driving planet gears, torque transmission, and transmission ratio control

Application Scenarios

Common Faults & Troubleshooting

• Pitting/spalling: Caused by poor lubrication, overload, or high contact stress. Replace 3121153 sun gear and inspect lubrication system, meshing status of planet gears and ring gears.
• Tooth breakage: Caused by impact overload, misalignment, or fatigue fracture. Replace with new sun gear, check load, installation accuracy, and shaft stiffness.
• Scuffing/burning: Caused by lubrication failure or high oil temperature under high-speed heavy load. Replace sun gear and lubricating oil, check cooling and lubrication system.
• Abnormal wear: Caused by insufficient surface hardness, foreign matter, or improper assembly clearance. Replace sun gear, clean gearbox, and adjust meshing clearance.
• Abnormal noise/vibration: Caused by sun gear wear, poor meshing, or bearing failure. Inspect tooth surface, meshing clearance of 3121153, and support bearings.