Jeff asked:
Can I weld any steel rebar or are there specific grades to look for?

Our Answer:
Not all rebar can be welded, particularly with the exothermic welding process as it must be able to heat the surface of the metal rebar to the melting point in order to ensure adhesion.  In general, only steel rebar that is “Grade W” can be welded.

According to Wikipedia: The American Welding Society (AWS) D 1.4 sets out the practices for welding rebar in the U.S.  Without special consideration the only rebar that is ready to weld is W grade (Low-alloy — A706).  Rebar that is not produced to the ASTM A706 specification is generally not suitable for welding without calculating the “carbon-equivalent”.  Material with a carbon-equivalent of less than 0.55 can be welded (AWS D1.4).

Rebar cages are normally tied together with wire, although welding of cages has been the norm in Europe for many years, and is becoming more common in the US.  High strength steels forprestressed concrete may absolutely not be welded.

Here is the link: http://en.wikipedia.org/wiki/Rebar

We hope you find this information useful.  Feel free to contact us again should you have any further questions.

The Engineering Experts at E&S Grounding Solutions