IEC Fusion Reactor Mark 3 Vacuum Hub



The Mark 3 reactor vacuum hub was constructed out of the Mark 2 reactor concept prototype vacuum hub.


Cross (2005):

2.75" CF cross, 2 rotatable flanges. Cross will serve as the reactor vacuum hub, providing vacuum connection, an electrical feed through, and one instrumentation well.


Throttling Valve (2005):

Throttling butterfly valve is added to vary pumping rate. A NW-25 to 2.75 conflat adaptor attaches to the top of the throttling valve to adapt the vacuum hub to the vacuum system.


Vacuum hub (2005-2006):

Assembled vacuum hub.

  • NW-40 adaptor on bottom was subsequently replaced with thin wall bellows to attach to core
  • Electrical feed through on top was subsequently replaced with a blank off.
  • Blank off on right was subsequently replaced with a 2.75" CF to male 1/4" VCR adaptor to connect to convectron and gas handling system





Bellows (01/20/2008)

Thin wall bellows will connect core to vacuum hub. Bellows will seal to conflat flanges with viton o-rings.


Bellows clamp flange (01/20/2008)

Bellows mount is machined out of G10-FR4 fiberglass and is electrically insulating, allowing the core to be electrically insulated from the vacuum system and frame. Mounting lip is 0.1" deep.




Bellows clamp flange (01/20/2008)

Clamp flange on bellows and spare pair showing mounting groove.


Bellows o-ring (01/20/2008)

O-ring seals bellows to core and insulates vacuum hub from core allowing current monitoring and biasing on each hemisphere.


Bellows clamp (01/20/2008)

Groove in clamp compresses the bellows' lip against the o-ring.


Bellows clamp (01/20/2008)

Both clamps tighten down clamping bellows to core conflat. The o-ring on the vacuum hub is compressed by the springiness of the bellows until it is under vacuum, where the atmospheric pressure creates a hard seal.


Bellows spacer (2/06/2008)

Spacers are inserted between the flanges to prevent the bellows from collapsing under vacuum.


O-ring retaining ring (2/19/2008)

Retaining ring is inserted into top o-ring to prevent it from slipping while under vacuum.

Retaining ring GCODE


O-ring retaining ring (2/19/2008)

Retaining ring is inserted into top o-ring to prevent it from slipping while under vacuum.




Useful links: Open Source Fusion Research Consortium.





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