NH₄-HPAN combines four core functions: reducing filtration loss, preventing collapse, increasing viscosity, and resisting contamination. It eliminates the need for multiple single-function treatment agents, achieving comprehensive optimization of the drilling fluid system. It boasts outstanding filtration loss reduction, rapidly adsorbing onto clay particle surfaces to form a dense and tough filter cake, effectively blocking water leakage, stabilizing the wellbore, and significantly reducing the risk of collapse and narrowing. Its anti-collapse performance is excellent: ammonium ions inhibit the hydration and expansion of clay minerals, enhancing formation stability, especially suitable for easily collapsing shale and mudstone formations. Viscosity control is flexible: it can moderately increase drilling fluid viscosity and shear stress, improving proppant carrying capacity and preventing cuttings buildup and stuck pipe, without significantly increasing flow resistance. Its strong anti-contamination ability: it exhibits good tolerance to salts, calcium and magnesium ions, and formation contaminants in the drilling fluid, maintaining system stability and reducing treatment agent losses due to contamination. This “one agent, multiple effects” characteristic greatly simplifies drilling fluid formulation, reduces the types and amounts of treatment agents used, and lowers the overall cost of raw material procurement and on-site preparation, offering a cost-effectiveness far exceeding that of single-function products.
