Field test of 311 mm vertical drilling system

Packed hole and well straightening issues are common classical crux which could not be solved completely. The Karamy Drilling Technology Research Institute of the Western Drilling Engineering Company finally develops the 311 mm active vertical drilling system with independent intellectual property rights after many years of research. The drilling system was separately tested at T82066 and T82065 well in September and November 2009, great success was obtained. From the characteristics of the structure of the system, combining with field practice, this paper analyzes and discusses the field test program, test difficulties and solutions as well as procedures. Test course and effect are illustrated and analyzed. Test proves that the 311 mm vertical drilling system has remarkable packed hole and well straightening effect and fast drilling capacity during drilling in precipitous tectonic structure formations, formations with high inclination angle, faults, and formations with abnormal in-situ stress. Its application could be promoted further.