Abstract

This paper will discuss the progress that has been made in the development of multi-lateral completions with a broader scope of application than those originally used in competent rock formations. Although numerous multi-lateral wells have been drilled in Austin Chalk, a more sophisticated completion method is required to maintain borehole stability, flow control, and well maintenance capabilities in other lithologies. With this purpose, a project was undertaken to develop a multi-lateral system that would 1) mechanically connect the lateral liner to the parent casing, 2) allow through tubing re-entry access to selected laterals, and 3) seal the junction between the lateral and parent bore so that flow control capability could be maintained. In addition to incorporating the criteria listed above, in the system subsequently developed, the hole size of the lateral has been maximized in comparison to the parent wellbore casing, and full bore access to the lateral liner drift ID without restriction has been provided. Bench tests of the components of the system have been performed, and a full scale system test has been conducted. The system has been fully installed in two wells. These completion experiences are discussed in the case history section of this paper. Other field installations are also in progress.

An integrated development approach with a multi-disciplinary design team and direct producing company involvement was used in development of this technology and was critical to achieving its success.