Method of treatment of pipelines and other steel surfaces for improved coating adhesion

A method for applying a protective coating to the interior of a steel pipeline, in situ, comprising the step of:

• cleaning the interior of a steel pipeline to remove at least one of solid and fluid contaminants from an inside wall surface of said pipeline and providing said wall surface with a roughness of at least 0.05 mils;
• providing a quality of a coupling agent for adhering a polymeric coating to said wall surface, said coupling agent comprising an organosilane having at least two functionalities, one of said functionalities providing a bond between said surface and silicone in said organosilane, the other functionality comprising a non-hydrolyzable organic radical providing a bond with a polymeric coating;
• displacing a slug of said coupling agent through said pipeline to deposit a film of said coupling agent in said wall surface;
• and
• applying a polymeric coating to said film, said polymeric coating selected from a group consisting of epoxies, polymines, polymides and vinyl esters to minimize corrosion of said pipeline.

A method for preparing the surface of a carbon steel article for application of a protective coating, comprising the steps of:

• cleaning a surface of a carbon steel article to remove at least one of corrosion products and contaminants from said surface and providing said surface with a roughness of at least b 0.50 mils;
• providing a quantity of a coupling agent for adhering a polymer coating to said surface, said coupling agent comprising an organosilane having at least two functionalities, one of said functionalities comprising a hydrolyzable group providing a bond between said surface and silicon in said organosilane, the other functionality comprising a non-hydrolyzable organic radical capable of providing a bond with a polymer coating selected from a group consisting of epoxies, polyamines, polyamides, and vinyl esters;
• applying said coupling agent to said surface in a solution of one of water, alcohol and a hydrocarbon fluid;
• drying said coupling agent on said surface;
• and
• applying a polymer coating to said coupling agent, said polymer coating selected from a group consisting of epoxies, polyamines, polyamides and vinyl esters.