Herrenknecht Tunnel Boring Machine

The Herrenknecht EPB Shield S-300 mega tunnel boring machine was built to excavate a road tunnel in Madrid in 2005. Yep, that’s a 21′ diameter central cutting wheel surrounded by an additional outer cutting wheel which yields a maximum excavation diameter of around 45’ at a time. It’s not just big, it’s the biggest ever built.

It reminds me of the sand worms in the Frank Herbert novel Dune. This thing is incredible; not only does it churn up the stone and bedrock it’s blowing through, it also pulverizes everything to pebbles and ships it to the rear via a huge conveyer for removal and other use. The best part: this mega tool only puts a few operators into harms way instead of the hundreds of people required for blasting. Bravo, Herrenknecht.