Key Points for Bending Serpentine Heat Exchange Tubes

Serpentine tubes are core components of heat exchangers, widely used in refrigeration, HVAC, solar energy and industrial cooling systems. Precise bending directly determines heat exchange efficiency, service life and assembly accuracy. Operators must strictly follow technical standards to avoid tube cracking, deformation and dimensional errors.

First, select suitable raw tubes and pre-inspect materials before bending. Copper, aluminum and stainless steel tubes for heat exchange are mostly thin-walled. Check for surface scratches, pits or uneven wall thickness. Hardened pipes need annealing treatment to improve ductility; otherwise, cracks will appear at bending arcs. Clean oil and oxide on tube surfaces to prevent mold abrasion during forming.

Second, set reasonable bending parameters. Wave height, pitch and bending radius shall match design drawings. Too small a radius causes tube collapse and inner wall wrinkling, blocking fluid circulation. Servo equipment needs calibrated feeding speed. Excessively fast feeding leads to inconsistent wave shapes, while low speed reduces production efficiency. All serpentine waves must keep uniform spacing to ensure neat assembly of heat exchanger fins.

Third, protect tube surfaces during forming. Custom matched molds with smooth inner liners avoid scratches on thin walls. Add lubricant moderately to reduce friction, but excessive lubrication leaves residues that affect welding later. Clamping force should be moderate: too tight crushes tubes, and loose clamping shifts positioning, resulting in irregular serpentine coils.

Fourth, control post-bending inspection and storage. After bending, check each arc for cracks, flat deformation and size deviation. Damaged tubes must be scrapped instead of being assembled. Finished serpentine coils shall be placed flat to prevent rebound distortion. Avoid heavy extrusion during transportation.

In summary, standardized material inspection, accurate parameter adjustment, surface protection and finished product inspection are four critical links. Strictly following these notes stabilizes product quality, reduces rejection rates and guarantees stable heat exchange performance of serpentine tubes.