Key Points for CNC Bending of Welded Tubes — Avoid Weld Seam Cracking Defects
Target Keywords：CNC bending welded tube, weld seam cracking solution for tube bending
Welded steel tubes are widely used in hardware and furniture manufacturing due to cost advantages. Weld seam cracking is a frequent process headache during CNC bending.
Weld zone material structure differs from base metal with residual welding stress. Cracking easily occurs if weld seam locates at outer tension side during bending.
Core rule for welded tube processing: Position weld seam away from tension zone; place weld on inner compression side or neutral side. Keep consistent weld orientation during loading.
Use larger bending radius whenever possible. Cracking risk rises sharply under small R radius. Source tubes with well ground internal and external weld beads. Apply mandrel support for thin wall welded tubes.
Run sufficient trial bends before mass production. Weld position deviation among raw tubes can cause random cracking. Use loading fixtures to guarantee uniform weld orientation for every tube blank.