stress-relieved strand for prestressed concrete

[IYYAPPAN_R]

I am looking for more information on the following: The green strand passes through a induction furnace under tension. For example equipment provider of induction furnace for this purpose. More information on the type etc.

 

[Ingenuity]

Your question is not clear to me. The following graphic may be of assistance:

FYI - most (all?) 7-wire strand for prestressed concrete manufactured today is low-relaxation - which has both stress-relieved properties and also lower relaxation properties than just S-R strand.