The Automatic Annealing and U-Bending Transfer Machine is designed to manufacture hairpin and foldback heating elements within one continuous production process, from straight heating elements to fully tested finished components.

The machine consists of two synchronized processing sections, connected by an automatic transfer system that moves each heating element through every stage of the manufacturing process.

First section: Annealing and preparation

• Automatic loading unit — operators prepare the batches on a high-capacity flight-bar loading conveyor; from there, a CNC handling arm picks up each element and centers it for the first working stage
• Central spot annealing unit — passes electric current through the element to anneal its central zone (the U-bend point), while a dedicated sensor continuously monitors the sheath temperature for consistent process control
• Cooling unit — cools the annealed element uniformly to prevent distortion and preserve dimensional accuracy
• Lateral double spot annealing and cooling unit — anneals and cools the two lateral zones of the element, for foldback parts whose additional bends require it

Transfer to second section — the element is re-centered and a second set of CNC handling arms transfers it to the post-bending section

• U-bending unit — bends the element into its hairpin shape; the station is designed to minimize stress concentration at the bend apex, for higher product quality and longer element life
• Hydraulic squeezing unit — compresses the bend radius with high precision, reducing it to allow tighter center-to-center spacing between the legs while preserving material integrity and preventing internal wrinkles
• Pressing unit — re-compacts the bend through a dedicated forming die, ensuring repeatable, dimensionally uniform bends
• Electrical testing unit — performs dielectric strength (hi-pot) and ohmic value tests; the terminal-probe system engages the pins reliably even with slight misalignment
• Automatic unloading unit with scrap sorting — automatically removes from the production flow any element that fails testing or is damaged during bending; the unloading system can be fully customized to integrate with downstream lines and automation