دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a bit that does not have a uniformly round cross section;instead, the bit has a protuberance that projects from one side. An eccentric bit drills a hole slightly overgauge to compensate for certain formations, such as shale or salt, that deform and enlarge after being drilled. Eccentric bits can also ream undergauge holes.

n: the pterate bit with big and small flushing port and arranged eccentricly