GB/T 21958-2017 in English

4.3.7 Temperature rise control requirements

The standard stipulates: After 3 hours of continuous operation, the oil temperature ≤90℃ and the temperature rise ≤70℃. Implementation points:

• High thermal conductivity housing material is required
• Lubricating oil viscosity should meet 90-110mm²/s at 40℃
• See Appendix H for test method, and record temperature-time curve

4.3.10 Limited slip differential function

New requirement of locking coefficient ≥ 0.4, test method (Appendix I):

1. Use a bidirectional torque loading device
2. Keep the total torque T₀ unchanged, and adjust the torque difference between the left and right wheels
3. Record the torque value when the speed difference reaches 5r/min

Key points of production process control

• Gear processingStrictly implement the 6th level accuracy requirements of JB/T 5615
• Assembly environment cleanliness control ≤50mg/L (4.3.4)
• Air tightness test must use 1.1-1.2 sugar value leak test liquid

Testing equipment configuration suggestions

1. Steering endurance test bench (Appendix D): must have ±5% torque control accuracy
2. Hydraulic test system (Appendix B): Class B measurement accuracy (pressure ±1.5%)
3. 3D coordinate measuring machine: used for bridge housing deformation detection