Demagnetizing Gas Piping: Safe Methods Explained

[William Brown]

< Mentor Note -- thread moved to HH from the technical engineering forums, so no HH Template is shown >[/color]

Hello and thank you for your time, OK enough of that Question I have is
(1) A gas pipe in-service 16" .375 wall X52 carbon pipe and has been depressurized & cold cut and to weld a new spool piece to replace old on. At this time it was found to be magnetized. What is the safest way to demagnetize pipe to be welded?
I have read two ways. One is with heat but no one has told me the temperature which could be a factor in the integrity of the pipe and two rapping the lead but which end the positive or negative and which current electrode positive or electrode negative
Please explain in full detail & thank you very much

 

[Simon Bridge]

What is the safest way to demagnetize pipe to be welded?

Look up "deGaussing" - the welding process will re-magnetize the pipe.
i.e. http://www.engineerlive.com/content/22345

 

[davenn]

(1) A gas pipe in-service 16" .375 wall X52 carbon pipe

I was reading this and thinking what the ?

how can you magnetise a carbon pipe ... then I realized the OP omitted an important word ... steel as in carbon steel