Plan Optimization and Drilling Construction of High Pressure and High Gas Well Tangdong9X2

Abstract

Tangdong9X2 is a preliminary prospecting well in the coastal fault nose structural belt in Tangdong Area of Dagang Oilfield. The well has a plan measured depth (MD) of 5135 m and characteristics of deep reservoir buried depth, complex geological conditions, multiple sets of pressure systems and high gas content. Based on the detailed analysis of the regional drilling data of the existed wells, drilling technical difficulties of the well are summarized. By geology-engineering integration and software simulation, precise trajectory optimization is made. With the formation pressure prediction technology, further casing program optimization is made. According to the regional characteristics, the precise managed pressure drilling (MPD) technology is selected, and the supporting technical measures for rate of penetration (ROP) and drilling effect improvement and cementing technical plan are made. Through plan optimization, the successful construction of Well Tangdong9X2 is ensured, and “zero complexity and zero accident” safe drilling is realized during the whole drilling process, with remarkable ROP improvement. The average ROP is increased by 40.29% compared with the adjacent wells, and the high-yield industrial oil and gas flow with daily oil production of 230.49 m3 and daily gas production of 28860 m3 is obtained. The success of the well not only provides a reliable basis for the follow-up well construction in Tangdong Area, but also provides a reference for the safe drilling of similar oilfields.