Study and application of smart pack completion technology

The drilling part of the full term underbalanced drilling and completion technology is easy to achieve underbalanced operations, but the completion part is difficult. To solve the difficulties of high cost when using casing valves and limited application scope when using open-hole completion, smart pack completion technique was proposed. It uses some gel system to separate the upper killing fluid from the formation, so as to protect the formation. By a large number of experiments, optimal choice of smart pack recipe was selected, and the smart pack recipe was studied in view of pressure tolerance performance, strength, sealing performance, stability, gelation time, gel breaking time, operation technique, and flow-back technique. Field tests on ten wells, including Well Niudong89-912 and Well Ya940, showed the technology not only solves the passive situation of relatively simple underbalanced completion method, but also achieved the objectives of high effeciency and low cost.