Demagnetize a Railcar

[dynopepticman]

We have a 55 ft. long open top gondola railcar that is magnetized. We suspect that these cars are loaded and unlaoded with scrap metal using magnetic cranes, hence the magnetism in the car. Our problem is that we need to repair weld some structural members on the car and the magnetism causes the weld pool to spatter all over, making the task impossible. Is there any advice out there on how to demagnetize the car or otherwise proceed.

 

[ornerynorsk]

Are you sure it is the magnetism that is causing weld problems? Have you tried some different welding alloys that are specific to dirty/rusty conditions? A monster size de-gaussing coil is the only way I can think of to demagnetize something that large.

 

[hacksaw]

portable degaussers work.

there are a dozen other methods, that qualified weldors know, the trick is to hire them

 

[ISUClone]

If it is a localized area you need to weld there are hand held units that can demag a small area (6" square). I reccomend you contact someone like Magnaflux. They do magnetic particle inspection but part of the process is to demagnitize everything they mag, some of these items are quite large...

 

[morgothia]

ok the easy way is to buy a small scale de-mag coil try it out on the area about to be welded these coils are cheap and easy to obtain they are used in the tv industry to de-mag video screens hope it helps



morg

 

[Theo2004]

Very important: If the bearings are magnetized to, it make improper for using on railcar. You must demagnetized the
I don’t know about how to demagnetize the body of a railcar, maybe you must search for a local solution just for the weld task.
Or look on

http://www.gaussbusters.com/

 

[umreng]

If you really want (need) to demagnetize the entire railcar, you should read the article at the following link:

http://www.redlandsfortnightly.org/subm.htm

During WWII, submarines and other ships were actually demagnetized to help them avoid detonating submerged German mines armed with rigged compass contacts. This is an interesting account hidden in a rather lenthy novel-ette.

If you can get by with a partial treatment, contact a welding expert and pay him/her to show you how to partially demagnetize a specific area of the car using two DC welding machines and coiled up, extra long welding leads.