Horizontal Well Completions - George E King Petroleum ...

Drilling Fluid Operating “Window”• Mud density must be higher than the porepressure to keep fluids from entering the well.• Mud density must control tendency of shale tospall particles into wellbore• Mud density must be less than the formationfracture (extension) gradient – corrected forfriction pressures while circulating. The pressureexerted by the fluid at any depth is a function ofits density plus the friction pressure in thecirculating path back to the surface.3/14/2009 31George E. King EngineeringGEKEngineering.com