cast iron pipe

Ed and Dave are right...not weldable.....methane present. Replace with ABS black pipe. It's not that hard to do, and you'll be better off. Put a clothespin on your nose. (kidding)

[Ed Heimbach]

When cast sewer pipe was new, It was made of almost the worst quality iron available(being a low profit item, the good iron was used elsewhere).
Welding is not an option, as there is too much contamination in the iron for it to weld, also, it is most likely too thin.
Best option is to replace it, either with new hubless pipe, or, if codes allow, plastic.
(I'd go with plastic, it is so easy to work with).

[Twell]

Well, I couldn,t replace the pipe or fit any couplers on it without cutting it or screwing with about 7 cemented connections. This pipe connects to the bathroom so their is waist flowing through it.

I will get back to you on the specs.

Thanks

[Dave Haak]

Cast Iron Pipe

Twell,

Can you provide a little more info? Like, size, position- vertical or horizontal with some slope? I am assuming this is all exposed and inside a building. Are the bad spots all in one area? Would a fernco type coupler work? They are just a rubber boot with hose clamps at each end. No welding would be required. If several locations, you might need to remove and replace section or sections of pipe. How about support? Ceiling pipe hangers? Wall standoffs? My first thought would be to not weld cast iron pipe, not that it can't be done. Also, is this vent piping or for actual sewage? Code might allow PVC.

Dave

P.S. About the explosion part: It would be a possibility. If you have a direct connection to municipal sewer or even with a trap, if it has dried out. Methane gas is bad news.

[Twell]

I was wondering how to weld cast iron (sewage) pipe with stick. The pipes are starting to show little points of corrosion. I was thinking og just patching the bad spots with steel and using a nickle rod. Is explosion a possibility?
Thanks