Five Years of Drilling with Casing in Argentina and Bolivia. Lessons Learned from the Field

摘要

Drilling with Casing (DWC) has been used in over 500 strings in the last 5 years in Argentina and Bolivia. The objective of this paper is to summarize the experiences and share the lessons learnt in those years from the perspective of casing connections manufacturer. Within this paper several cases where drilling with casing technology has been used in Argentina and Bolivia. For each case there will be an explanation of the drivers behind the use of the technology, the challenges that arose during the field implementation and the lessons learned. Special attention will be given to the casing connections, the tools and services required and the limitations. In Argentina and Bolivia drilling with casing has been used in extensively, in mature fields and shale applications. In all cases the objective was to reduce cost and improve efficiency during drilling. However the drivers where not always identical, in some cases the technology aimed to overcome drilling difficulties as wellbore stability and circulation loss; in others reduce NPT and increase efficiency. The analysis of the experiences with drilling with casing technology indicates that there are two critical stages for the project: engineering and field operation. In the first, the analysis of fatigue, torque and buckling shall be done properly to reduce risks and hazards, being fatigue the less known and more difficult to assess. Regarding the second, the experience shows that improper handling and use of connections could lead to sudden and unexpected failures compromising the project sustainability. The results are summarized in a list of recommendations. The experiences from the field have led to the development of specific tools and services aimed to extend the benefits of the technology to other areas. Furthermore, the data collected will shape the design of next generation of casing connections. A guideline to select and operate casing connections in drilling with casing applications based on extensive field experience.