US Patent 9765577 Method for making pipe centralizer having low-friction coating

A method of fabricating a centralizer for a tubular body in a wellbore is provided herein. The method includes providing a centralizer, wherein the centralizer include an elongated body having an inner surface and an outer surface, and wherein the inner surface defines a bore there through. The bore is dimensioned to slidingly receive a tubular body. The method also includes applying a first low-coefficient of friction treatment to the inner surface and the outer surface using a ferritic nitro-carburizing process. The method further includes depositing a second low-coefficient of friction treatment onto at least the inner surface. The coatings are designed to provide a reduced coefficient of friction on the surfaces.