First Experience in the Application of Radial Perforation Technology in Deep Wells

摘要

This paper describes the first application of radial perforation technology with hydraulic jet and coiled tubing in deep wells with complex geometry. Radial perforation technique utilizing hydraulic energy is being used in different places around the world with good results. Its main application is intended for marginal fields, with low productivity and shallow wells with depths between 1000m and 2000m, normally having simple geometry. Basically, several perforations can be made with this technology, in an existing well (mother well), perpendicular to the well axis and at several productive levels, thus improving the production profile around the main well or mother well. Repsol YPF Bolivia has adopted this technology to perform a pilot test in fields with good to moderate recovery and in deep wells with complex geometry (directional wells with depths between 3500m and 3900m). This operation was performed in three wells (Surubi A1, Paloma C7 and Surubi Bloque Bajo 109) in the Mamore Block in Bolivia. The main challenge for this operation was to adapt equipment and tools used up to that time, to much more severe operational conditions due to greater depths, tortuosity, type of formations to be drilled and mechanical conditions of the wells. The main subjects covered by this paper are: 1. Introduction 2. Characteristics of the reservoir and objectives for the application of this technology. 3. Geometrical and mechanical characteristics of the wells. Operative results. 4. Description of the equipment and main adaptations to new operative conditions. 5. Main problems encountered. Solutions. Operative limitations. 6. Conclusions. The results indicate that this technology may continue being an attractive substitute for other stimulation techniques, such as fractures, acids, side tracking, etc, even with higher costs implied by its application to complex wells and with the improvements that will definitively be applied to current tools and equipment