The two massive tunnel boring machines that will do the first drilling for the Gateway Rail Tunnel between New York and New Jersey are now in North Bergen, laid out in components across a construction ...

Boring Company Prurfock 3 and the new Prufrock 4 tunneling machines can only tunnel about 11 hours per day. There are limitations are maintenance and how they have to stop tunneling to put in the ...

Here's how the tunnel boring machine, or TBM, works: As the 200-ton TBM moves forward, a round cutter head studded with titanium teeth grinds into the tunnel face and splits large chunks off the rock.

Tunnel boring machines (TBMs) are very picky about the rocks they chew through. This is why geologists must monitor the rock at the head of every tunnel. On good days, TBMs can bore through rock at a ...