Application of high-performance water-based drilling fluid system in Mahu oilfield

Abstract

The Baikouquan Formation in Block 18 of Mahu Oilfield, Xinjiang, is easily hydrated with mud shale; it exhibits poor cementation speed, low mechanical drilling speed, and high accident and complexity rates during drilling. The existing water-based drilling fluids show poor inhibitory properties, insufficient lubrication and anti-seize, and insufficient plugging ability for pores and micro-fractures, so it cannot easily satisfy construction requirements. In the present study, a strong inhibitor YZFS-1 and a wall-fixing agent GBFS-1 are introduced based on the existing water-based drilling fluid system to build a set of high-performance water-based drilling fluid system that has successful applications in a well. As revealed from the results of its field application: XZ high-efficiency water-based drilling fluid system exhibits stable rheology, low filtration loss, robust suppression ability and regular well diameter, and without the presence of downhole complex accidents. As compared with adjacent wells, the system of this study exhibits high drilling speed, a short cycle, low cost and significant effects, providing a solid technical guarantee for safe and efficient development in the area.