Method of sequentially forming anti-corrosive coatings

A method of treating metallic surfaces of an oil or gas pipeline, comprising the steps of:

• providing an anti-corrosion system including separate quantities of a first component including an epoxy resin active ingredient in a first compatible dispersant, and a second component including a curing agent active ingredient for the epoxy resin in a second compatible dispersant;
• initially contacting said metallic surfaces with one of said first and second components and causing the corresponding active ingredient to at least partially coat said metallic surfaces;
• passing a fluid separate from said first and second components over said at least partially coated metallic surfaces;
• and
• after said initial contacting and fluid-passing steps, subsequently contacting said at least partially coated metallic surfaces with the other of said first and second components, and causing the active ingredients of said components to react with each other and generate an anti-corrosion layer,
• said method further comprising the steps of
• placing a first shiftable pig within said pipeline;
• performing said initial contacting step;
• placing a second shiftable pig within said pipeline, with said first component located between the first and second pigs;
• allowing oil or gas within said pipeline to pass behind said second pig;
• placing a third shiftable pig in said pipeline, with said oil or gas between said second and third pigs;
• performing said subsequent contacting step;
• and
• placing a fourth shiftable pig in said pipeline, with said second component between the third and fourth pigs.

A method of treating metallic surfaces of oil or gas recovery or conveying equipment during use of the equipment or recovery or conveying oil or gas, comprising the steps of:

• providing an anti-corrosion system including separate quantities of a first component including an epoxy resin active ingredient in a first compatible dispersant, and a second component including a curing agent active ingredient for the epoxy resin in a second compatible dispersant;
• initially contacting said metallic surfaces with one of said first and second components and causing the corresponding active ingredient to at least partially coat said metallic surfaces;
• passing a fluid separate from said first and second components over said at least partially coated metallic surfaces;
• and
• after said initial contacting and fluid-passing steps, subsequently contacting said at least partially coated metallic surfaces with the other of said first and second components, and causing the active ingredients of said components to react with each other and generate an anti-corrosion layer,
• said initial contacting, fluid-passing and subsequent contacting steps being carried out during use of said equipment when oil or gas is being recovered or conveyed.