When U.S. forces attacked Iran’s nuclear facilities on June 21, 2025, the main target was metal tubes in laboratories deep underground. The tubes are centrifuges that produce highly enriched uranium needed to build nuclear weapons.

Inside of a centrifuge, a rotor spins in the range of 50,000 to 100,000 revolutions per minute, 10 times faster than a Corvette engine’s crankshaft. High speeds are needed to separate lighter uranium-235 from heavier uranium-238 for further collection and processing. Producing this level of force means the rotor itself must be well balanced and strong and rely on high-speed magnetic bearings to reduce friction.

Over the years, Iran has produced thousands of centrifuges. They work together to enrich uranium to dangerous levels – close to weapons-grade uranium. Most of them are deployed in three enrichment sites: Natanz, the country’s main enrichment facility, Fordow and Isfahan. Inside of these facilities, the centrifuges are arranged into cascades – series of machines connected to each other. This way, each machine yields slightly more enriched uranium, feeding the gas produced into its neighbor to maximize production efficiency.

As a nuclear engineer who works on nuclear nonproliferation, I track centrifuge technology, including the Iranian enrichment facilities targeted by the U.S. and Israel. A typical cascade deployed in Iran is composed of 164 centrifuges, working in series to produce enriched uranium. The Natanz facility was designed to

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