The principle function of oil-well cementing is to bond and support the casing, and to provide downhole zonal isolation. However, the residual non-aqueous drilling fluids (oil-based mud) on the surface of steel pipe can weaken the bond to the hardened…
The principle function of oil-well cementing is to bond and support the casing, and to provide downhole zonal isolation. However, the residual non-aqueous drilling fluids (oil-based mud) on the surface of steel pipe can weaken the bond to the hardened cement. The most practical way to analyze the bonding between cement slurry and steel pipe is to directly measure adhesion between these two materials. In the present study, the cement cylinder and the steel coin are separately fixed in two sides of a Brazilian disk, and then the force is applied along the diameter of the disk, at an angle to the interface between the cement and steel. The preliminary results from Brazilian disk tests show that shear bond strength is quite different for the two commercial spacers. Another important factor is the surface condition. Polished, sandblasted and rusted coins are used to examine the effect of surface conditions. Better adhesion is obtained on rusted steel surfaces.