Fault Phenomenon: Komatsu WA380 wheel loader bucket cutting edge is loose, bolts cannot be tightened.

Troubleshooting Process:
– Checked bolt holes: holes in bucket body worn into an oval shape.
– Checked bolts: bolts sheared and deformed.
– Checked material: local hardness of bucket insufficient.
– Checked operation: prolonged overloading pushing hard materials.

Root Cause: The bucket cutting edge mounting bolt holes were worn and elongated due to long-term impact loads and bolt loosening, making it impossible to secure the cutting edge.

Required Parts: Repair bucket body (bushing or build-up weld and re-drill) or replace bucket assembly.