New advances on damage evaluation technology for drilling and completion fluids in horizontal wells.
WANG Yong-heng, KANG Yi-li, CHEN Yi-jian, YOU Li-jun State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum Institute, Chengdu, Sichuan
The researchers home and abroad always looked for damage evaluation technologies for horizontal reservoirs due to no sufficient considerations on the singularity of formation when evaluated by conventional experimental apparatus. The researchers abroad developed special core holders for the horizontal well to determined formation damage such as the experimental apparatus for simulating radial flow of the horizontal well and the triaxial multiple cores holder for determining damage suffered from the top, lateral and bottom of the horizontal well. Except for the dynamic damage evaluation system exposed to HTHP as well as the long core evaluation system, the experts home also developed a multifunctional damage evaluation system which gave a full consideration on the effects of nonisotropy, time and drilling rigs eccentricity on the damage caused by drilling in the horizontal well so that the damage process and mechanism of the horizontal reservoir were understood better.