Drilling Efficiency WithCasing While DrillingTechnique in South Rumaila (Iraqi Oil Field)

Current drilling operations are located in troublesome zones that may have severe lost circulation and wellbore instability which contribute to Non-Productive Time (NPT) while drilling. These challenges contribute to develop Casing while Drilling (CwD) technique. This paper presents case studies of the implementation of CwD technique in south Rumaila oil field in Iraq.CwDhad proven to be an effective technique to overcome Dammam formation problem by reducing cost and time of curing this problem. Also, the total time saving in both NPT and time spent in Dammam were ranging from 79% to 94% and from 54% to 70% respectively.