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Using EMP To Punch Holes In Steel 165

angrytuna writes "The Economist is running a story about a group of researchers at the Fraunhofer Institute for Machine Tools and Forming Technology in Chemnitz, Germany, who've found a way to use an EMP device to shape and punch holes through steel. The process enjoys advantages over both lasers, which take more time to bore the hole (0.2 vs. 1.4 seconds), and by metal presses, which can leave burrs that must be removed by hand."
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Using EMP To Punch Holes In Steel

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  • by drDugan ( 219551 ) * on Saturday January 16, 2010 @12:31AM (#30787718) Homepage

    The article focuses on how this is a more "peaceful use" for the EMP. I disagree: when the robot apocalypse finally arrives, and a rogue T800 drives after you in into a steel mill, it will be damn useful to have an EMP device used for shaping steel rings handy to stop the cybernetic killing machine. As an added benefit, an EMP would destroy the cpu, meaning no Cyberdyne Systems, and I get my 5 hours back wasted on T3 and Terminator Salvation!

    The mechanical press was, like, so 1984.

  • Longevity? (Score:3, Interesting)

    by afidel ( 530433 ) on Saturday January 16, 2010 @12:32AM (#30787722)
    The site the wear on machine dies as a factor, but what's the expected number of discharges that these super-capacitors can be expected to survive, the coils?
  • by peacefinder ( 469349 ) <> on Saturday January 16, 2010 @12:52AM (#30787820) Journal

    I won't say never, because people who say "That'll never be practical!" are inevitably made to look like idiots at some point. That said, it's hard to imagine this working well for punching applications.

    This process seems to have some inherent disadvantages for punching holes. Compared to an ordinary turret punch, the tooling will be very expensive and will take a tremendous amount more power to operate. It is also not clear if EMP tools will be able to punch arbitrary shapes, or how the press would operate in an industrial setting without damaging its own working area or doing Something Unfortunate with the waste metal, or if it can operate at anything like the speed of a flywheel-driven punch. The may of course be certain applications where it will become valuable or even indispensable, but for general-purpose punching, I don't see it.

    For forming applications it's a very interesting idea, though.

    • by Hadlock ( 143607 )

      They don't mention how this compares to high pressure water jets, which I would assume is both faster and cheaper than laser, and doesn't leave any burrs. I'm not an expert in sheet metal forming, so someone feel free to correct me, but while I'm sure EMP will have very specific uses in the future, hydro-cutting will remain a better option in 99% of situations for the forseeable future.

  • Metal presses (Score:3, Informative)

    by zygotic mitosis ( 833691 ) on Saturday January 16, 2010 @12:53AM (#30787836)
    Not all burrs left by a punch press need to be removed by hand. Small pieces may be burnished, rotoblasted, or vibratory finished. Still takes time, I guess.
  • Article Has No Meat. (Score:5, Informative)

    by bmo ( 77928 ) on Saturday January 16, 2010 @12:55AM (#30787846)

    Hi. I'm a metalworking professional, with a heavy background in tool and die work.

    >metal presses, which can leave burrs which must be removed

    The burr side, if you've got sharp tooling, doesn't have much of a burr. Also, when you assemble the product, the burr side goes away from the user. Speaker grille material, for example, is always mounted on the finished speaker burr side in. If you've got a large burr punching holes in steel, then you have dull tooling and/or wrong punch-to-die clearance.

    >.2 seconds per hole

    Too slow. Much, much too slow. Call me when it can equal 600 strokes a minute on a conventional press.

    >by hand

    Someone's never heard of tumbling, flame deburring, electrochemical mass finishing, etc.

    >This article is written as if there's no tooling involved and there's no die or stripper plate to back up the steel as it's distorted by the EMP. It goes on to say that it can do away with molds. LOL QUE?

    Total misunderstanding by the journalist.


    • by bmo ( 77928 )

      To follow up, a conversion error by the journalist:

      Pressure of 3500 atmospheres.

      That's not 3 small cars. That's 17.5 Volkswagen Golfs (2010).

      • Re: (Score:3, Informative)

        According to my source [] a typical Volkswagen Golf 2010 Rabbit weighs 3100–3250 pounds or 1410-1480 kg (rounded) and since 1 atmosphere is very nearly 10N/cm^2 and a 1 kg mass exerts ~10N force we can conclude that 3500 atmospheres is like balancing ~2 and 1/2 Volkswagen Golf 2010 rabbits on a 1cm^2 area. So the journalist wasn't that far off from the truth this time.

    • >by hand

      Someone's never heard of tumbling, flame deburring, electrochemical mass finishing, etc.

      That's great if your part doesn't have a very high tolerance. If you're machining pieces for the aerospace industry, those methods will totally ruin the part.

    • Re: (Score:3, Insightful)

      by grimJester ( 890090 )

      >.2 seconds per hole Too slow. Much, much too slow. Call me when it can equal 600 strokes a minute on a conventional press.

      600 a minute is .1 seconds per hole, not so far from .2. Did you misread it as 2? Presumably a process without physical moving parts can be speeded up more easily as well.

  • Water jet? (Score:3, Interesting)

    by sunderland56 ( 621843 ) on Saturday January 16, 2010 @01:00AM (#30787878)
    Everyone I know in the metal manufacturing field is currently using water jet technology to cut holes. Easier, cheaper, and neater than lasers; and cuts any arbitrary shape, unlike a die punch. And - very importantly - safe for the operator.

    So how come no comparison in TFA with water jet? EMP doesn't sound like it can do intricate shapes, and they're only going through very thin steel. Why replace a proven inexpensive technology with a new inferior one?
    • Re:Water jet? (Score:4, Informative)

      by Anonymous Coward on Saturday January 16, 2010 @02:09AM (#30788218)

      I run a water-jet at a university, but I prefer a laser cutter or plasma cutter for CNC work. The water-jet is a pain to keep running. High pressure air and water, tubes, orifices to replace, mixing tubes that wear out, water filters, etc. Maintenance nightmare. I prefer to just have to clean the optics once in a while on a laser cutter and I can tell you that the laser cutter we have cuts much sharper than our water-jet.

      The advantage of the water-jet? Will cut 4" of ANYTHING for one thing, and it will cut the brittles like glass and ceramics and stone that the others will not. Also rubber - I cut a lot of rubber with it.


      • Re: (Score:3, Insightful)

        by atamido ( 1020905 )

        Also rubber - I cut a lot of rubber with it.

        I feel like there's a great joke in here that I can't quite put my finger on.

  • Someone help me out here as I'm not a physicist, but if this machine produces enough physical force to punch a hole through steel, does it offer any possibility of being used as a propulsive force?

    • What you are thinking of is called a railgun which works along the same principle only this time the metal projectile isn't tethered to anything.

      • Not necessarily a rail gun, but specifically the fact that this can produce enough physical force to actually punch through the metal. what happens if you unhinged this 'punch' so that it wasn't anchored and ramped up the force at a slower pace?

        I realize this specific implementation would need metal to interact with, but I have to wonder if they can and will eventually learn to interact with gravitational fields from objects like the earth itself.

        • The field strength falls off considerably as you move away from the metal target which means that the force applied on the metal also dropps off rapidly. As for interacting with gravitational fields (I assume you mean manipulating them) with our current physics knowledge, manipulation of gravitational fields isn't possible to ny degree that is really useful. You can however, if you create a strong enough magnetic field, repel agaisnt the Earth's magnetic field (100+ teslas) however this is a very strong f

        • its called a monorail
          • its called a monorail

            And there's nothing on earth like a genuine, bona fide, electrified, six-car monorail!

      • by hitmark ( 640295 )

        the comparison to a railgun is probably more correct then first thought of.

        when i think about it, this EM-punch is basically just a railgun without the ammo. Or rather, the ammo is outside the "gun".

        basically, one is building up a EM pulse so fast and so focused that one push parts of the metal out of the way faster then the surrounding metal can adapt, and it tears.

        if the setup is designed correctly, the same system can potentially bend and punch just by adjusting focus and strength. A quick brainstorm sug

    • Re: (Score:3, Informative)

      by camperdave ( 969942 )
      I doubt it would be very effective. Here's what's happening. A large power source builds up a charge in a bank of supercapacitors. This charge is fed into a coil, generating a magnetic field. The coil induces an equal but opposite field in the steel. The two fields repel each other, and since the coil is fixed in place, the steel under the core of the coil gets flung out of the way.

      Now, if you had the large power source, the supercapacitors, the massive coils, and the supply of steel out in space, th
  • to power the damn thing. Go Iter!
  • by tjstork ( 137384 ) <todd DOT bandrowsky AT gmail DOT com> on Saturday January 16, 2010 @01:49AM (#30788146) Homepage Journal

    I have to ask the question, if, the EMP can punch so much faster than the laser, couldn't the guy that makes the laser just make one that is more powerful, and therefor, cuts faster? It seems to me that this comparison in the article is more of a selling pitch than a legitimate comparison of EMP vs the laser for metal working.

    • Re: (Score:3, Informative)

      No. The problem with laser cutting is that when the laser vaporizes material off of the target, the vaporized material obstructs the beam to a degree which fundamentally limits the rate at which the laser can cut. Another concern is that lasers aren't the most efficient things at converting power into the coherent laser light necessary to cut through metal. It may be more efficnet from an energy standpoint to use the EMP punch rather than the laser.

  • Magnetic forming (Score:3, Informative)

    by Animats ( 122034 ) on Saturday January 16, 2010 @03:49AM (#30788554) Homepage

    This, as the article points out, is basically a beefed up version of magnetic forming. Magnetic forming has been around for decades. It's useful mostly for compressing cylindrical objects, so it's used on couplings, tube joints, and similar round objects I've seen it used in making hydraulic spool valves. It's a way to apply a completely symmetric radial squeezing force, which is hard to do at high precision with stamping dies or presses. Here are some examples of parts formed by magnetic forming. []

    But for punching holes, there's no obvious advantage to magnetic forming.

  • "Your passport doesn't work, sir"
    "Oh sorry, I work in a metal factory. I guess the passport ought to have had shielding"

    Oh yes - probably deniability..

  • Quite apart from potentially being fun to look at, it would have really helped to see a short clip of this in action. It could have informed things like: how thick the metal, how wide the hole, ...

Thus spake the master programmer: "When a program is being tested, it is too late to make design changes." -- Geoffrey James, "The Tao of Programming"