6 1/2" PDC rock bits tungsten carbide drilling machine for oil drilling
6 1/2" PDC rock bits tungsten carbide drilling machine for...
20" IADC537 new big size hole opener bit/reamer/Assemble reamer bits for rock drilling horizontal directional
20" IADC537 new big size hole opener bit/reamer/Assemble...
6 3/4" IADC217 big size hole opener bits with tricone rock drill bits
6 3/4" IADC217 big size hole opener bits with tricone rock...