This is a video taken in 6000 feet of water. An undersea robot is sawing a 3mm wide slit (1/10th of an inch ... REMEMBER THAT WIDTH) in a pipeline. The pressure inside the pipeline is 0 psig, while the pressure outside is 2700 psi, or 1.3 tons per square inch. Then a crab comes along....
http://burningsmell.dyndns.org/crab