Casing While Drilling technology is one of the greatest developments in drilling operations. The Casing While Drilling involved drilling and casing a well simultaneously and hence, overall cost of drilling may be reduced significantly by lessening drilling time and drillstring problems encountered during conventional drilling process. This technology is highly applicable in depleted reservoir as an alternative to the underbalanced drilling, which requires special equipment.

This paper presents the applicability of the concept of Casing While Drilling in context of the Arabian (Middle East) drilling operations. Attempts are made in order to overcome some unscheduled hole problems, such as lost circulation, differential sticking and casing stuck due to tight hole during running casing after drillstring pulled out.

This paper also presents simplified method that has been developed to predict the torsional and drag forces subjected to the casing string. Method of evaluating fatigue life of casing string has also been developed using simplified analytical techniques based on prevailing drilling conditions in Arabian fields. Both the static and dynamic cyclic loads as encountered in vertical and deviated wells are considered for the evaluation of fatigue life of casing string used for Casing While Drilling. Valuable guidelines are provided based on field representative case studies in order to minimize the various problems of conventional drilling operation through using the Casing While Drilling approach for Arabian field condition.

You can access this article if you purchase or spend a download.