My system that I'm working on at the moment was almost all wrought iron pipe. Although in much better condition. Some as new as the 30s and stamped "Genuine Wrought Iron" on the side. No corrosion on the insides of most of the pipe at all. I was able to cut and thread all of the old dry return pipe to make new dry returns and move them across the basement for the downstairs conversion from 1 pipe to 2 pipe. I'm done with almost all the downstairs radiators except the one I'm adding to the enclosed porch. The water main for my house is also made of wrought iron. Well over 100 year old 1 inch wrought iron pipe. I had to thread it recently because someone had put a brass compression fitting on it which was causing corrosion. The inside of the pipe was pristine aside from some mineral buildup. Copper water pipe in the same house develops pinhole leaks in a few years but wrought iron and galvanized steel seem to last forever. But that's the water up here for you. Attacks copper and leaves ferrous metals alone. PEX gets chewed up by mice. So CPVC or galvanized are really the only good options for piping because of how corrosive the water is to copper here. I've read that Ductile Iron has a similar corrosion resistance to wrought iron. What I decided to do in the next stage of the project (boiler installation) is use threaded ductile iron fittings for everything below the water line. The 300psi rated ones that are pretty expensive. As well as schedule 80 pipe. There is a price difference but I'd like this to be a very long lasting system so I figured I would go all out on the best of everything. Above the water line I used all cast iron (mix of domestic and imported) for the piping I did and the original piping still has its ancient cast iron fittings. The wrought iron pipe seems easier to start a thread (with a manual threader) but harder to continue that thread to the end. What I've found fascinating is that in different parts of the system I've found a few different types of pipe thread. Not different in pitch but thread profile. Close enough that a standard thread will screw in with slight difficulty. When reading my 1917 Crane catalog I found a section talking about how they standardized the threads in 1910 or thereabouts.
I just think you had a defective piece of pipe. I started in 73 and we used to pipe oil burners for heavy oil and just run the pipe underground from the oil tanks with the pipe buried in the ground. A lot of the engineers would specify "wrought Iron" pipe for use underground as it was thought to resist rusting better than steel pipe. We used to have a pile of it on our pipe rack. You couldn't tell it from steel pipe by looking at it, but the wrought iron pipe was delivered with a stripe of red paint on it. As I recall it was harder on the pipe dies and more difficult to thread.
Don't I know it! They positively go gaga over the stuff. All that stringy silicone slag and soft iron. But for plumbers, wrought iron pipes eat sawzall blades like chicklets.
My system that I'm working on at the moment was almost all wrought iron pipe. Although in much better condition. Some as new as the 30s and stamped "Genuine Wrought Iron" on the side. No corrosion on the insides of most of the pipe at all. I was able to cut and thread all of the old dry return pipe to make new dry returns and move them across the basement for the downstairs conversion from 1 pipe to 2 pipe. I'm done with almost all the downstairs radiators except the one I'm adding to the enclosed porch. The water main for my house is also made of wrought iron. Well over 100 year old 1 inch wrought iron pipe. I had to thread it recently because someone had put a brass compression fitting on it which was causing corrosion. The inside of the pipe was pristine aside from some mineral buildup. Copper water pipe in the same house develops pinhole leaks in a few years but wrought iron and galvanized steel seem to last forever. But that's the water up here for you. Attacks copper and leaves ferrous metals alone. PEX gets chewed up by mice. So CPVC or galvanized are really the only good options for piping because of how corrosive the water is to copper here. I've read that Ductile Iron has a similar corrosion resistance to wrought iron. What I decided to do in the next stage of the project (boiler installation) is use threaded ductile iron fittings for everything below the water line. The 300psi rated ones that are pretty expensive. As well as schedule 80 pipe. There is a price difference but I'd like this to be a very long lasting system so I figured I would go all out on the best of everything. Above the water line I used all cast iron (mix of domestic and imported) for the piping I did and the original piping still has its ancient cast iron fittings. The wrought iron pipe seems easier to start a thread (with a manual threader) but harder to continue that thread to the end. What I've found fascinating is that in different parts of the system I've found a few different types of pipe thread. Not different in pitch but thread profile. Close enough that a standard thread will screw in with slight difficulty. When reading my 1917 Crane catalog I found a section talking about how they standardized the threads in 1910 or thereabouts.
I just think you had a defective piece of pipe. I started in 73 and we used to pipe oil burners for heavy oil and just run the pipe underground from the oil tanks with the pipe buried in the ground. A lot of the engineers would specify "wrought Iron" pipe for use underground as it was thought to resist rusting better than steel pipe.
We used to have a pile of it on our pipe rack. You couldn't tell it from steel pipe by looking at it, but the wrought iron pipe was delivered with a stripe of red paint on it. As I recall it was harder on the pipe dies and more difficult to thread.
Fascinating information. tHanks for the video
Glad you enjoyed it!
Any blacksmith would gladly take wrought iron piping off your hands!!
Don't I know it!
They positively go gaga over the stuff.
All that stringy silicone slag and soft iron.
But for plumbers, wrought iron pipes eat sawzall blades like chicklets.
I didn't realize that. I will save the wrought iron rather than scrapping it. I didn't know....
I'm hoping to drop this off to a local blacksmith!
Not all pipe from this era (1880s to 1920s) is wrought.
Steel pipe was cheaper, I believe.