Failed drill pipe
Below is portion of a drill pipe that failed in service. Laboratory examination revealed it had become so hot by friction that the microstructure was altered. The red numbers superimposed on the cross section indicate the hardness in Brinell, where the steel had been reaustenitised and hardened after it had screwed itself apart.
Failed rig anchor rope
A failed rig anchor rope is shown in a. below. Individual wires were failing in the manner shown in b., with unusual feature being the fibrous fracture shown in c. Metallographic examination revealed the wires had internal manufacturing faults, as arrowed in d.