Corrosion Investigation in Polyethylene Coatings Used in Cooling Water

The corrosion of pipelines' coatings is one of the main problems in oil and gas industries for which a large amount of money is spent each year. Coating is the first defense line in front of a corrosive environment in which pipes have been buried. Good function of coating depends on its adhesiveness rate to the metal surface. Initial adhesiveness and its durability in the contact conditions are among those factors that enhance coating efficiency in long term. The rate of Initial adhesiveness has a high relationship with coating movement and surface wetness by this movement in the course of applying the coating and also with cleanliness and preparedness of pipe surface. Corrosion in oil and gas wells has the electrochemical mechanism, When the system reaches a temperature below the dew point, moisture is converted to liquid and many droplets occurs on the pipe's wall. In the electrochemical reaction, water plays role of the electrolyte. In this book we propose and teach some way to decrease corrosion in oil and gas industries.