DRILLING FLUID ADDITIVE FOR LOSS CIRCULATION AND WELLBORE STRENGTHENING

摘要

A method for controlling the loss of drilling fluid from an oil well borehole into formations penetrated by a drill bit is disclosed by which resilient graphitic carbon particles having a resiliency greater than about 130% rebound after compression to 10,000 psi; a degree of graphitization greater than 85%, as measured by d002 using XRD; an average pore size larger than 0.035 micron; and an aspect ratio smaller than 0.63 are added to the drilling fluid.