Casing Drilling Technology as the Alternative of Drilling Efficiency

Abstract The drilling technology was developed to increase the drilling efficiency based on 3 basic reasons, i.e.: safety, minimum cost, and usable hole. Casing drilling is one of drilling technology which it has been applied in many oil fields in Indonesia. The casing drilling is classified into 3 methods, i.e.: Retractable Bit, Liner Drilling, and Drilling with Casing, where each method can be applied in certain condition. Recently, the drilling technology has reached efficiency significantly, both in engineering and economical aspects, especially in the formation which is difficult to drill with conventional drilling method, for examples: ❑Abnormal/subnormal zone❑Thief/loss zone❑Unstable formation Generally, the drilling efficiency can be formulated based on statistic trend from the field data. Thus, casing drilling can be developed to reach the drilling efficiency according to the field experiences.