Magnetized Steel Plate Problems???

[BryanDowdy]

We've been having issues getting magnetized steel plate for the last 8-10 months. I'm pretty sure our steel supplier gets their steel from US Steel. I will be talking with our supplier, but wanted to see if anyone else has ran into this lately. 1/2" A36 seems to be the worst. Have had a few sheets of 3/8" & 1/4" show signs of magnetism, but the 1/2" is by far the worst. We are cutting the sheets on our cnc plasma table then welding. Never had problems welding it, but had major problems cutting it. We've been through around 25 tons of 1/2" since this problem started and we've have 1 sheet cut fine, so it's not like we got a bad batch of plate. Maybe it's just our luck, but interested to know if anyone else is having problems.

[tackit]

Do you think it's possible the sheets got magnetized by the steel suppliers crane magnet?


http://www.em-chicago.com/Large-Scal...g_Systems.html the

[BryanDowdy]

Only if the mill used magnets to load the sheets. Our supplier unloaded the at our shop straight from their semi coming from the mill.

[jrscgsr]

Get a gauze gauge and see what it's reading.

[BryanDowdy]

I'm working on getting one. I sent a piece to Hypertherm's test lab and they came back with it's magnetized.

[Dipsomaniac]

I'm working on getting one. I sent a piece to Hypertherm's test lab and they came back with it's magnetized.

Do you know how strong the magnetic flux was in the plate steel?

[BryanDowdy]

Do you know how strong the magnetic flux was in the plate steel?

Not yet, trying to find someone with a gauss meter

[weldonwelding]

Find the biggest sledge hammer you ever saw, place the metal on saw horses with wood in between. And smack it with all ya got.... if that don't work turn it over n try it again

[Lars Brownlie]

Gauss and DC / GMAW robots

I believe that we are also having arc blow, wandering and other issues that may be related to magnetism. I picked up an analog gaussmeter of 20,0,20 range. All it tells me is that we have some issues with fixture bumps, some square tubing as well as some heavy plate. On numerous occasions, my analog meter goes off the 20 scale. I should have gotten a field meter that reads 100/0/100 instead since DC / GMAW and 40 gauss do not play well together. I admit was being cheap since I bought it myself. I am supposed to locate and get a quote on a good electronic meter to determine if we actually have an issue with magnetism, and also to begin determining what the next logical step would be.

I have been looking at the FW Bell 5170/5180 gaussmeter as well as the Diverse Magmeter MF300+. The MF300 appears to be built a bit more ruggedly and has less controls to work on the unit. Neither one is cheap. I do not really need datalogging. The FW Bell seems to have a lot of unneeded functions in it.

Anyone have any suggestions here? What would be the next logical step if we are actually having gauss problems?

[Lars Brownlie]

Magnetism and DC GMAW robotic fixtures

I have been checking for magnetism with a 20/0/20 analog meter. I should have gotten a 100/0/100 version since 40 gauss and GMAW do not play well together.

I have been reading plate, square tubing and robot fixture bumps off the 20 scale on my field meter and am supposed to locate a good electronic unit.

Has anyone had any experience with either the FW Bell 5170/5180 or the Diverse Magmeter MF300H+? The Magmeter appears to be more durable and simpler in design over the Bell unit.

Any suggestion as to where to start in this issue?