Welding Wrought Iron (not Cast Iron) to Carbon Steel

[visitor]

Has anyone ever developed a welding procedure for welding wrought iron piping either to other wrought iron piping or common carbon steel piping. Note: I am not trying to weld cast iron! My application is working in a very old piping system that made use of wrought iron piping nearly 50 years ago. I am now attempting to add to and maintain the system. Annecdotal evidence with "old time" welders is that they used standard oxy-acetylene stick welding without any problems except getting the pre-heat just right. Wrought iron is a very malleable material - almost malleable to a fault in a piping system.

Also, since the material specifications for wrought iron piping seem to have been rescinded by most standards organizations decades ago does anyone have any copies of those old standards?

Thanks in advance. Kind of an obscure topic.

 

[sbc]

Stick welding is recomended for wrought iron
alloy SAE 4130 or 4340. Oxy-acetylene welding
will also work, but you are heating a larger
area.

 

[gdodd]

According to some old reference books left over by my predecessor, wrought iron is readily weldable without the use of a flux. As wrought iron is high in silicon and low in carbon the microstructure consists essentially of ferrite plus particles of iron silicate. The iron silicate acts as a flux making wrought iron readilly weldable by any of the common welding processes. In addition, the silicates act as a barrier confining corrosion to the surface protecting the iron from pitting, making it suitable for water pipes.

This stuff is so versatile I'm surprised it isn't more popular.

 

[visitor]

Thanks for the feedback. I think wrought iron was very popular but it wasn't exceptionally strong. I did a little more digging after my post and found that it was also fairly expensive to make wrought iron relative to modern carbon steels. Most WI processes were batched instead of a continuous. About the only time you see WI now is in decorative railings, furniture, etc. It is getting harder and harder to find WI.

 

Dear Sir, I have recently taken a job as a fabricater welder
and i am expected to weld cast iron to mild steel by mig welding, I am at the moment finding it very difficult.
could you please advise if this is possible.
Many thanks Don.

 

[sbjuke]

when welding cast you have to heat and test with a temp stick.....around 500 degrees.........use nicad or 7018 stick......or braze.....mig won't cut it......