Coatings for Steel Water Pipe

finity of corrosive agents for iron, it is desirable that a permanent coating be applied to the interior and the exterior of the water pipe to act as a barrier against all corrosion attacks. A protective coating of proper type for existing conditions will prevent deterioration of the metal. Pipe laid underground is subject to soil stress, erosion, electrolysis, and chemical, physical, galvanic, and bacteriological action. It is essential, therefore, to determine the magnitude of these various factors so that a completely protective coating can be selected economically and scientifically to offset their detrimental effects. The purpose of this paper is to assemble and summarize present knowledge on the subject of available coating materials, their effectiveness, and their approximate cost of application. This discussion will be confined to steel w r pipe 4 in. or more in diameter, as manufactured under specifications AWWA C201 (i) and C202 (2). The references listed at the end of this