Session: 11-02-01 Well Drilling Fluids & Hydraulics

Paper Number: 122473

122473 - Oil-Based Fluids Behavior on Experimental Cuttings-Bed Erosion in Horizontal Wells 

Efficient removal of deposited cuttings-bed is a necessity during drilling operations. Nevertheless, is a big challenge specially at horizontal wellbores as larger beds are formed and gravity tends to consolidate the formed beds. Poor cuttings cleaning might cause several problems such as, drill-pipe sticking, increased torque and drag, lower Rate of Penetration (ROP), excessive Equivalent Circulating Density (ECD), among others. Removal of the drilled-cuttings is done by the drilling fluid flow thru the annulus and out to the surface.

This paper presents laboratory tests results from a deposited cuttings-bed using quartz sand wetted by different oil based fluids in a lab bench scale setup and the flow of a low viscosity oil with Newtonian behavior as cleaning fluid to erode the formed bed. As well as wet-granular rheology of the wetted beds to analyze the cohesive forces imparted by the oil-based fluids into the sand grains to form a consolidated cuttings-bed.

The results have shown that cuttings-bed wetted with oil based fluids present lower cohesive force than cuttings-beds wetted with water based fluids, but even with that lower energy required to move the particles, turbulence should be achieved by the cleaning fluid in order to effectively erode a deposited bed.

Presenting Author: Camilo Pedrosa NTNU

Presenting Author Biography: PhD candidate in chemical engineering from NTNU with more than 8 years of industry experience both in drilling fluids and oil-well cementing.

Authors:

Camilo Pedrosa NTNU
Bjørnar Lund SINTEF
Arild Saasen University of Stavanger