Editing Enriched uranium (section)

====Zippe centrifuge====
{{main|Zippe-type centrifuge}}
[[File:Zippe-type gas centrifuge.svg|thumb|upright|Diagram of the principles of a Zippe-type gas centrifuge with U-238 represented in dark blue and U-235 represented in light blue]]

The Zippe-type centrifuge is an improvement on the standard gas centrifuge, the primary difference being the use of heat. The bottom of the rotating cylinder is heated, producing convection currents that move the <sup>235</sup>U up the cylinder, where it can be collected by scoops. This improved centrifuge design is used commercially by [[Urenco Group|Urenco]] to produce nuclear fuel and was used by Pakistan in its nuclear weapons program.