Drilling Fluid Drilling: A Critical Step in Oil and Gas Exploration

Drilling Fluid Drilling: A Critical Step in Oil and Gas Exploration

Drilling fluid drilling is a crucial step in oil and natural gas extraction. To ensure efficient and safe drilling while preventing well loss and blowouts, drilling fluids must be used throughout the drilling process. Today, drilling fluid has become the lifeline of oil wells.

Drilling fluid is a viscous, mud-like mixture of water and soil, which is pumped into the borehole by drilling workers. Although it is still commonly referred to as "mud," engineers no longer rely solely on water and soil as the base materials for drilling fluid. Instead, they carefully formulate its composition to meet the specific requirements of various drilling conditions.

In oil and gas drilling operations, drilling fluids typically possess shear-thinning properties and excellent thixotropy. Under high shear rates, such as at the drill bit nozzles, the viscosity of the fluid decreases, which facilitates high-pressure jet drilling. Conversely, at low shear rates (in the annulus), viscosity increases and shear force becomes stronger, which helps carry sand and cuttings to the surface.

Drilling fluids must exhibit good thixotropy so that when circulation stops, the shear force can quickly increase to an appropriate level. This aids in the suspension of cuttings without causing excessive pump pressure when restarting circulation. As deep-well drilling technology advances, drilling depths continue to increase, and the temperature and pressure endured by fluids inside the well rise significantly. As a result, research into the rheological properties of drilling fluids under high-temperature and high-pressure conditions is becoming increasingly important.