On August 2, 2021, the successful completion of 5,436 meters of the Su Dong 014-113H Well marked the successful completion of this difficult well with drilling fluid technical services provided by ZOOE. While ZPEC drilling fluid breaks the record in this block again, the first-class products and technical services have established a good reputation as well.

Su Dong 014-113 Well is located in Hu JiaHao village, Hong Qinghe Town, Yi JinHolo Banner, Ordos City, Inner Mongolia Autonomous Region. It is a development horizontal well deployed by CNPC Chang Qing Oilfield. The design well depth is 5,437 meters. The main target strata are Shi Hezi Formation and Shanxi Formation. With a large displacement of 2,924 meters and a horizontal section of 2,511 meters, the well is the longest horizontal well constructed by ZPEC in its history.

The large section of sandstone encountered in the third horizontal section of Su Dong 014-113 contains mudstone. The sand layer has high friction resistance, is easy to seep and collapse, the mudstone is easy to absorb water and swell, and it is difficult to trip. The completd wellls in  same block have difficulties in BHA balling, necking, tripping, leakage in various degrees. Some  wells even caused huge economic losses due to inadequate casing running. Faced with the complex bottom hole conditions and the design of the ultra-long horizontal well section of off-site wells, the ZPEC Group Company, Project Department, and Drilling Team paid high attention to the design of drilling fluid schemes, discussed and formulated effective schemes through multiple video conferences, and finally selected the company’s high-performance water-based mud system ZM-HP, which was applied to this well.

During the drilling process of the horizontal section, the technical experts of ZPEC personally stayed on-site to guide, strictly implemented the construction plan, and adjusted the drilling fluid performance in time according to the on-well conditions. During the construction process, the system showed good lubricity and inhibition, especially with ZPEC's self-developed plugging agent, ZM-MAGICSEAL, which effectively guaranteed the stability of the long horizontal section of the wellbore and provided a guarantee for the safe and efficient completion of the drilling target.

The successful completion of Su Dong 014-113 demonstrates that the high-efficiency water-based mud system can fully meet the construction requirements under complex conditions, which greatly saves drilling cycle and drilling costs. It also fully shows the technical strength of ZPEC drilling fluid in complex and difficult wells.

(Mr. Ren Hong)