A Cementing Technology for Horizontal Shale Oil Wells in Shahejie Formation of Shengli Oilfield

The cementing of horizontal shale oil wells in Shahejie Formation of Shengli Oilfield faces some technical challenges, such as the difficulties in the casing centering and safe casing running, high performance requirements for cement slurry, and hard displacement of oil-base drilling fluids. In light of these, the amphiphilic flushing spacer system was developed , the fiber expanding and anti-channeling plastic latex cement slurry system were optimized. On this basis, a cementing technology was formed preliminarily for horizontal shale oil wells in Shahejie Formation of Shengli Oilfield by combining cementing equipments and measures including an integral elastic casing centralizer, an eccentric guide shoe, floating displacement, and annulus pressurization, etc. The cementing technology was tested on site in a preliminary prospecting well YYP1, with a normal cementing operation completed. The results of acoustic amplitude logging showed that the cementing quality of the first interface was quite high, and that of the second interface was qualified. As indicated by the research and tests, the proposed cementing technology can tackle technological problems in cementing for long horizontal sections of horizontal shale oil wells in Shahejie Formation of Shengli Oilfield and enhance cementing quality. It meets the requirements of large-scale volumetric fracturing for the cementing quality of cement sheaths and can be promoted and applied in the development of shale oil.