With HF induction welding, the induction coils must be located ahead of the tube mill's squeeze-roll assembly.
Although HF induction welding yields the highest stainless welding speeds at the lowest cost per unit length, cold-forming scrap rates can run as high as 20 percent.
Compared to HF induction welding, the key difference is that laser tube welding occurs at the squeeze-roll assembly.
In induction welding, induction heating of a gasket, made of a ferromagnetic-powder-filled bonding material, placed at the interface of thermoplastic parts to be joined, is used to melt the interface; subsequent solidification of the melt results in a weld.
The main difference is that for heating of metals a 0.2-0.5 MHz electromagnetic field is used, while induction welding of thermoplastics uses higher frequencies in the 3-14 MHz range.
PhedCorp designed an in-line assembly and testing machine that would receive cap blanks from a centrifugal bowl feeder, load them onto conveyor pallets in pairs, threaded-end-down, then advance the pallets through a sequence of stations including a leak-testing station positioned immediately after induction welding
Seven chapters of the book are devoted to welding methods including fusion and resistance welding, hot gas welding, induction welding
, spin welding, ultrasonic welding, vibration welding, and laser welding.
Historically, the electronic interference or "noise" that permeates industrial environments has hampered the development of reliable in-process weld-sensing controls for electromagnetic induction welding, according to Steve Chookazian, business manager of the Emabond Systems Business of Ashland Chemical.
In his view, electromagnetic induction welding overcomes those barriers by placing a thermoplastic compound filled with particles of a metal "susceptor" at the weld interface and subjecting it to a high-frequency magnetic field.