Ways to use electromagnets to pick up metal shavings at a distance
If you are trying to pick up shavings 12" from the magnet, that's probably not going to work, even with absurdly strong magnets. If it did work, what would you do with them THEN?

I'm having a hard time visualizing exactly what your setup looks like, but something that moved a magnet around the area so it was closer to the chips (and then moved it over a hopper, bin, or belt and turned off the magnet) might be more effective. Then again, ignoring the "magnet" aspect completely and mechanically sweeping, or vacuuming (as in a large air-transport chip collector, not a shop vac) might work (will depend somewhat on the nature of the chips - long, stringy, curly, sharp ones are much harder to handle than short chips.) 

If you have issues with build-up IN the machines, you may need to arrange air-blast or something to get them to the floor or collection system. Depending on what exactly the constraints are, something like a wide belt under each machine section that either dumps the chips where they can be safely collected as operations continue, or onto another belt that takes them away might work.