دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

v: to carry on drilling operations with a mud whose density is such that it exerts less pressure on bottom than the pressure in the fonnation while maintaining a seal (usually with a rotating head) to prevent the well fluids from blowing out under the rig. Drilling under pressure is ad- vantageous in that the rate of penetration is relatively fast;however, the technique requires extreme caution.