Paul Ryan, in the debate with Biden:
Let’s look at this from the view of the ayatollahs. What do they see? They see this administration trying to water down sanctions in Congress for over two years. They’re moving faster toward a nuclear weapon; they’re spinning the centrifuges faster.
I suppose we have to give Ryan a pass on this as a metaphor, but taken literally it makes little sense. Ex hypothesi Iran has competent nuclear engineers, otherwise there’s no major risk from its ambitions. For this reason, Gaddafi’s abortive nuclear weapon programme, abandoned in 2003, was taken seriously to be sure but never rose to an existential threat to anybody. So the Iranian engineers are surely running their centrifuges to their design limits.
According to the competent-seeming folks at GlobalSecurity.org:
The primary limitation on rotor wall speed is the strength-to-weight ratio of the rotor material. […] At present, maraging steel is the most popular rotor material for proliferants. With maraging steel, the maximum rotor wall speed is approximately 500 m/s. Fiber-reinforced composite rotors may achieve even higher speeds [advanced design carbon fiber rotors can exceed 600 m/sec]. However, the needed composite technology is not within the grasp of many potential proliferants. Another limitation on rotor speed is the lifetime of the bearings at either end of the rotor.[…]
Speeding up enrichment centrifuges isn’t like overclocking your PC processor – oops, reboot. You risk explosive failure, disruption of your cascade, and leaks of small but nasty quantities of corrosive and radioactive uranium hexafluoride gas:
The casing is needed both to maintain a vacuum and to contain the rapidly spinning components in the event of a failure. If the shrapnel from a single centrifuge failure is not contained, a “domino effect” may result and destroy adjacent centrifuges.
However, it’s a hopeful and pleasing image for the Romney-Ryan campaign. As their advanced mystification-enrichment machine spins faster and faster, it may explode, spreading fragments of radioactive BS all over the GOP ticket.