Bertha (tunnel boring machine) - Wikipedia

Cylinders are bored on a SERV-EQUIP boring machine to ensure bore is straight and round, ... These big bars are getting scarce and ha ...

Alaskan Way Viaduct - Follow Bertha

On Saturday,the world's largest tunnel boring machine was dedicated in the ... unexpectedly or if the cutterhead comes up against a boulder too big for it to ...

Large diameter boring on horizontal boring machine - YouTube

This modular boring system lets you bore holes up to eight inches in diameter on machining centers with 40-taper spindles.