Cathode – prize

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  • August 3, 2011 at 1:43 am #1200
    break
    Participant

    I have a question about the profitability of your “Focus Fusion”. If I understand correctly the cathode used in the FF-Reactor is worn, right?

    How long can you use a cathode? How long can you use a cathode under constant use? How much do a cathode cost and how complicated it is exchange?

    Is this a serious problem for the profitability and are there more components with a serious wear problem?

    ________________________
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    August 3, 2011 at 8:36 pm #10404
    vansig
    Participant

    cathodes are metal rods, that could be made longer than they need to be, and pushed into the chamber as they wear.
    adjustments could be done in micrometers; and may include turning, if needed. so servicing them is a matter of whether
    the fine adjustments may be made without taking the reactor offline.

    August 4, 2011 at 9:00 pm #10414
    zapkitty
    Participant

    More important is the rate of wear and the minimum time of a maintenance cycle.

    Per current LPP estimates an electrode assembly might last a month.

    Also per LPP estimates it will take about 9 hours for an FF unit to “cool down” to less than background radiation levels. So that’s ~9 hours cooldown, plus a couple of hours for unbolting and replacing prefabricated solid metal components. (And any other maintenance that might be needed by that unit.) Close it up and start it up.

    So, given currently available information, unless actual electrode life turns out to be measured in hours and not weeks then erosion isn’t going to be a show-stopper for FF plants.

    August 4, 2011 at 9:54 pm #10416
    AaronB
    Participant

    I suspect that before long, a robot located at the power station would be able to change out an anode in just a few minutes, regardless of radiation levels, so down-time may be limited to 30 minutes for a typical electrode swap. If one robot on a circular track was surrounded by 24 generators, it should be able to perform these replacements easily. We just have to design the generators to have easy robotic access and plug-and-play parts. In that case, even if the electrode life was 1 week, it wouldn’t be too bad.

    August 5, 2011 at 8:05 am #10418
    JimmyT
    Participant

    Mount such a robot on a truck to service solitary generators with little down time? Might be able to service several in a days time.

    Have to be very carefull about leaving a invisable trail of radioactive carbon dust traveling from site to site. Even if radioactive for only a few hours.

    August 11, 2011 at 5:27 pm #10450
    break
    Participant

    zapkitty wrote: More important is the rate of wear and the minimum time of a maintenance cycle.

    Per current LPP estimates an electrode assembly might last a month.

    Also per LPP estimates it will take about 9 hours for an FF unit to “cool down” to less than background radiation levels. So that’s ~9 hours cooldown, plus a couple of hours for unbolting and replacing prefabricated solid metal components. (And any other maintenance that might be needed by that unit.) Close it up and start it up.

    So, given currently available information, unless actual electrode life turns out to be measured in hours and not weeks then erosion isn’t going to be a show-stopper for FF plants.

    These are good news.

    But what about the cost of the cathodes? If all the energy of the earth is secured by “Focus Fusion”, then what about the supply with cathodes. Could there be problems with the resources? Can you recycle the used cathodes somehow?

    August 11, 2011 at 6:56 pm #10451
    vansig
    Participant

    cathodes are likely a few dollars each (as opposed to a few thousand), so i’m not worried

    August 11, 2011 at 9:50 pm #10455
    Tulse
    Participant

    And the cathodes should be able to be rehabilitated, or at least recyclable. The problems as I understand it are with changes to the surface shape of the cathodes, and not any effects on the actual composition of the material. It’s the equivalent to a knife getting nicks on its cutting edge (again, if I understand correctly).

    August 18, 2011 at 8:51 pm #10511
    vansig
    Participant

    abrasion of the surface, especially at the ends, could be a problem, but may possibly be mitigated by small, regular rotation; once you go around full-circle, it may be necessary to switch them out for polishing.

    i can just see it now,
    “sorry, honey; I cant leave work yet, i have to polish my cathodes”

    August 22, 2011 at 12:54 pm #10555
    annodomini2
    Participant

    vansig wrote: cathodes are metal rods, that could be made longer than they need to be, and pushed into the chamber as they wear.
    adjustments could be done in micrometers; and may include turning, if needed. so servicing them is a matter of whether
    the fine adjustments may be made without taking the reactor offline.

    One expansion of this, could be having a machining laser in the chamber to re-profile the rods and as you state an actuator to push the rods in a bit more once this process is complete.

    There would probably need to be some form of 3D scanning technology to tell the laser where to cut and how much material to take off.

    However the reactions would probably have to stop to perform this action.

    August 22, 2011 at 2:34 pm #10556
    zapkitty
    Participant

    annodomini2 wrote:
    One expansion of this, could be having a machining laser in the chamber to re-profile the rods and as you state an actuator to push the rods in a bit more once this process is complete.

    There would probably need to be some form of 3D scanning technology to tell the laser where to cut and how much material to take off.

    However the reactions would probably have to stop to perform this action.

    Much too expensive… you’re running away from the primary strength of the DPF: its cheapness 🙂

    Such a laser machining setup would literally cost more than the reactor itself. It would be simpler, faster and cheaper to replace and recycle the electrodes.

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