THE CORROSION in distillate wells is often localized. This is not a condition peculiar to distillate wells alone; but is common in many corrosive services, including oil wells. There are a number of reasons for localized corrosion occurring, and all cases can not be explained on the same basis. One factor frequently neglected is variations within the metal itself.
Metals are often thought of as being uniform materials. Such is not the case. It should be recognized that they are neither homogeneous nor ideal. The strength differs from section to section, the composition is not uniform, inclusions are present, and the crystalline structure varies. These differences affect the performance of a metal, including the manner in which it corrodes.
Corrosion is often associated with the ends of tubing. The ends of the tubes used in distillate wells are upset so as to provide a thicker section for threading. To upset...
