Hello everybody!!

I´m looking information about the posibility of welding by the flash butt welding process two low carbon steel bars (140x140mm square shaped cross section, in 35 seconds more or less). I would like to know what upsetting force and clamping force I need for this. Which are the differences between usig AC or DC current. Which current value would i need and what type of transformer? How would all this values vary with the temperature? (If the bars were at 100ºC, if they were at 500ºC, if they were at 1000ºC? Is the last one possible?). I would also thank all the information about the flash butt welding you could apport. Thanks to everybody and bye!!!

-- Iosu I. (A72372@gaviota.tecnun.es), November 22, 2002

Answers

The RWMA Manual, Fourth Edition, has a whole chapter on this and most of your questions can be answered in detail. A few general answers: Upset force: 15-20 KPSI Clamping pressure: Good electrical conductivity only required. Your wall thickness should not exceed 5mm. AC/DC: For this large of material and time, AC is the way to go. Current and Transfomer: Will have to be sized, more detail required. Time: 140mm doubtful you can do in less than 35 sec's. The folks in TJ Snow's application department are experienced in this type of operation, you should contact them. Kurt Tolliver Unitek Miyachi Corp.

-- Kurt Tolliver (kurt@unitekmiyachi.com), November 22, 2002.