Structural Magnets
Structural Magnets
(OP)
Anyone ever heard of or used a high strength magnet in a structural application, such as attaching ta bracket to the metal skin of a water tank?
Our in-house Archiitect has a web site he is sending me to look at, but I am skeptical at the moment. This would have to be a use that is tested and rated under the IBC, for, currently, there is no mention of using this type of force in the IBC.
Our in-house Archiitect has a web site he is sending me to look at, but I am skeptical at the moment. This would have to be a use that is tested and rated under the IBC, for, currently, there is no mention of using this type of force in the IBC.
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com






RE: Structural Magnets
The project got to complex and expensive so we went a more conventional route. I still wish that we could have continued.
RE: Structural Magnets
TTFN

FAQ731-376: Eng-Tips.com Forum Policies
Need help writing a question or understanding a reply? forum1529: Translation Assistance for Engineers
RE: Structural Magnets
What’s a “ta bracket?” Theoretically it should be possible. But, the question will always be, what are the consequences if it lets go (fails by any means) or slips in a frictional/shearing way, as Matt suggests, since it is not a permanent connection? Although, bolted and welded connections fail too. We use magnets now for lifting steel plates and the like, and use them as the bases for portable drills, etc. But, failure means a dropped plate or drill, or broken drill bit. I wouldn’t have any qualms about using magnets to fix a cloth banner (light banner) to a water tank for a short period of time, for example. Who guarantees that the magnet will never fail or slip, your in house Arch., not you.
RE: Structural Magnets
RE: Structural Magnets
I meant "a bracket". Sorry.
Ron:
I know, and that's one aspect of the design that I'm worried about. The Architect claims that they do not lose their magnetism, but that seems odd unless this is new technology.
The other thing is, will the magnetism be negatively afffected if it is hit by lightning? After all, the structure is a lightning magnet, not to be punny here.
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Structural Magnets
The analogue to current is extraordinarily sensitive to 'gaps' in the circuit. Even gage block surfaces are rough enough to be a magnetic gap.
Since magnet poles are typically planar, the curvature of the tank surface will interfere with the magnetic circuit, effectively producing a gap of variable dimension.
... unless one inserts a soft iron 'pole shoe' with one planar face and one face of curvature matching the tank. ... which introduces two smaller, but still finite, gaps in the magnetic circuit.
The paint on the tank also introduces a gap in the magnetic circuit.
The tank skin is likely too thin to not act as a restriction in the magnetic circuit.
Even if you get all of that right, the random huge currents and fields associated with a lightning strike can make it all go to hell.
I wouldn't consider a magnet mount anything on a water tank.
Magmount CB antennas barely work on a clean steel automobile roof.
Mike Halloran
Pembroke Pines, FL, USA
RE: Structural Magnets
As others mention I'd be as if not more concerned by the friction as by the magnets - unless there are some kinds of rips or similar physical features to pick up on.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Structural Magnets
Little did I know...
"We shape our buildings, thereafter they shape us." -WSC
RE: Structural Magnets
RE: Structural Magnets
RE: Structural Magnets
RE: Structural Magnets
Corrosion of exposed metal surfaces, accumulation of ferrous dust/crap around the magnets, and staining would be some concerns.
If it was placed where somebody COULD grab it, assume somebody will.
RE: Structural Magnets
-handleman, CSWP (The new, easy test)
RE: Structural Magnets
http://www.vestas.com/Files/Filer/EN/Brochures/Ves...
see page 10.
RE: Structural Magnets
Went with starring the post anyway. :D
RE: Structural Magnets
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Structural Magnets
In addition to the other problems noted above, the newer high-strength magnets are made from powder metallurgy (pressed and sintered powders). This means the materials are porous, which means there is a high probability that water and air will enter the part, regardless of anything you can do to seal/encapsulate the magnet. If the surface gets wet and the temperature can vary, you can guarantee that some moisture will penetrate. The magnet as a result slowly oxidizes internally, and loses strength over time.
RE: Structural Magnets
Mike Halloran
Pembroke Pines, FL, USA