Root Causes & Complete Solutions for Inner Side Wrinkles in CNC Tube Bending
Target Keywords：tube bending inner wrinkling, CNC tube bender wrinkle defect, eliminate bending wrinkles
Inner side tube wrinkling is a common CNC bending defect. Wrinkles reduce flow cross section for pipeline parts and reject cosmetic components.
Main causes: Misaligned anti wrinkle die; mismatched booster pressure / feed speed; improper mandrel position; thin tube wall and too small bending radius.
Solutions: Position anti wrinkle die tip near bending tangent point. Synchronize booster feed speed with main bending spindle. Deploy mandrel support for thin wall tubes. Increase bending radius if product design permits. Replace heavily worn dies.
Make small incremental parameter changes instead of large one step adjustments. Inspect inner forming quality on first samples. When design constraints forbid larger R radius, rely on optimized tooling combinations of anti wrinkle die and mandrel to suppress wrinkles.