DEEP DRILLING PUSHES TECHNOLOGY TO THE LIMIT.

This article discusses the present limitations of deep drilling technology. When bottomhole temperatures exceed 400 F and bottomhole pressures rise above 15,000 psi, corrosion problems are magnified. These high temperatures and pressures complicate decisions about the drilling fluid system and drill string program. Further, the pressure integrity of the deep liner and casing strings and the associated cementing jobs become more critical. Case histories and examples of problems and solutions are presented.