Flash-Butt Welding is an ultra-fast joining process with fusion occurring over the entire weld area simultaneously. It is the only resistance welding technique in which surface scale has little or no effect on the weld quality and consistency — a major reason for its use in pickling lines.
After trimming, flash-butt welds are as thin as the strip itself and pass readily through subsequent reduction and forming equipment. In most cases, the welds lose their identity and continue on into the consumer product.
Flash-Butt Welders predominate in pickle lines, but are also used in heavy-gauge Coil Preparation, Shot Blasting, Side Trimming and Slitting Lines, and Welded Tube and Pipe Mills.
Combination Flash-Butt Welders, appropriately named because they have a built-in, draw-cut weld trimmer which, in one stroke, removes the excess metal extruded to the surfaces of the strip during the upsetting (forging) portion of the welding cycle. A transfer mechanism successively moves the joint to the trimming station and other optional work stations, which include an edge punching or notching station and/or induction post-heating system. The latter minimizes costly strip breakage by tempering the heat-affected zone in alloy steels susceptible to treatment.
Weld equals parent metal thickness
Forgiving welding process compared to Laser and other joining processes.
- Skilled Trade personnel do not need extensive training to operate and maintain the welder.
- No need to release tension in your mill to pass the weld -creates a “Rollable Weld”.
- Less concern about weld breaking when moving across strip support and tension rolls.
- In many applications, the weld does not have to be removed before subsequent processing coating, annealing, or galvanizing the strip.
- No damage to seals, rolls or bearings when passing the weld through the line.
- Less waste and scrap.
- Lower initial investment, operating and maintenance costs than TIG, MIG or Laser welding systems.
- Fast cycle time – typically less than 60 seconds for the maximum width and thickness.
- Rugged “O” frame configuration.
- Hydraulic entry and exit clamps with quick change clamp liners.
- Precision linear motion control of welding platen.
- AC or DC weld current available.
- Automatic weld parameter set-up with “Upper Level” computer communication.
- Various PLC’s available – GE Fanuc, Siemens, Rockwell Automation (Allen Bradley).
- “Upper Level” computer communication via Profibus, Ethernet, or TCP/IP protocol.
- Matrix or algorithmic weld parameter adjustment control.
- Close-coupled transformer, secondary bus bar and welding electrodes – highest weld current density for any flash welder and lower energy usage!
- Automatic centering guides
- Automatic strip cross alignment
- Closed loop water chillers
- Notchers for trimming strip edges
- Weld quality “bulge” tester
- Weld temperature monitoring
- Weld wheel dresser