mealable iron fittings to carbon pipe

Date 12-01-2008 23:44

had a little fubar today.got a workorder to cut a nipple in half and add in a union to get to a draft tap on a coal pulverizer mill. Unfortunaly the nipple was the draft tap. It was basiclly a caped off 1" pipe with a slot cut through on side, that runs through a 2" y fitting with a bushing. My problem was that this had to be running in less than 2 hrs. So I made the draft tap, reamed out the threads on a mealable iron 300 lbs. 2" x 1" bushing and brazed it in with some fluxed brass rods. It was holding when I left. My question is if it leaks does anybody have a better welding solution for the meallable iron to carbon steel problem? We have screw pipe leaks all the time and the time it takes to tear apart a system to fix it could be avoided if I could weld or braze the leak.

By DaveBoyer (*****)

Date 12-02-2008 04:52

I think this should work, provided the parts don't get hot in service. I have arc welded malliable fittings to pipe, but this was FC2002 junk iron welding for sure.

By scrappywelds (***)

Date 12-02-2008 22:11

these parts will get warm I would say anywhere from 120 - 150 degrees. I know arc welding them sometimes holds, but mostly it cracks and leaks

By sbcmweb (****)

Date 12-02-2008 22:17 Edited 12-02-2008 22:21

Brazing is probably the best option & the best fix you could do with little time & circumstances. Like Dave said, as long as you don't get huge heat, or a lot of expending & contracting, you will probably be fine. I had to weld some cast decorative tops on some steel 5" tubing once. I did everything, preheat to peening & they still cracked. Every single one. I finally quit screwing around with the Nickel rod & just used Lo Hi. This was a total hack job working for a total hack, so it was acceptable. Braze is best for junk iron repairs like that. Besides the fact Nickel rod is expensive.

Good luck. S.W.