Causes and complete solutions for pipe clamping and indentation defects in CNC pipe bending machines

English Keywords：tube clamping marks, CNC bending surface scratches, tube indentation solution

Clamping indentations and scratches are critical defects for decorative tubes used in fitness equipment, furniture and sanitary ware. 

Main causes include hard steel clamping dies, excessive clamping force and worn die burrs. Steel dies easily damage stainless steel, aluminum and copper tubes. 

Effective solutions include replacing steel dies with nylon or copper-alloy protective dies, adjusting servo clamping force to avoid slipping or flattening, and polishing die surfaces regularly. 

Thin-wall tubes require gradual uniform clamping instead of instantaneous high pressure to eliminate surface marks completely.