Mechanical Study and Key Parameter Optimization of Temporary Plugging Fracturing in Tight Reservoirs

Abstract

Staging fracturing with balls for temporary plugging is a crucial technique used to stimulate deep reservoirs. However, the transport of matter confined in a trap is very complicated. To investigate the influence of various factors on the force exerted by the ball sealer during the construction of the temporary plug, we analyse the ball sealer migration in three stages: before, after, and after the pump is stopped. We examine the effect of density, viscosity, displacement, number of holes, and fracturing fluid viscosity on the confined force state of the spherical sealer. Based on a model of entrainment dynamics with three stress states, we analyse the motion and force properties of the sphere. With this analysis, we have identified the main factors that affect the force exerted by the ball sealer. Our findings suggest that reducing the number of holes, especially when using high displacement and high viscosity fracturing fluids, can optimize the force state of the plug sphere and increase the plug efficiency. This conclusion provides a theoretical foundation for the formulation and optimization of a staged FRAC construction scheme with plug balls.