Abstract: Paste flow patterns and microscopic particle structures were studied in a pressurized environment generated by a pulse pump. Complex loop-pipe experiments and fluid–solid coupling-based simulations were conducted. The scanning electron microscopy technique was also applied. Results revealed that flow resistance is closely related to pipeline curvature and angle in a complex pipe network. The vertical downward–straight pipe–inclined downward combination was adopted to effectively reduce the loss in resistance along with reducing the number of bends or increasing the radius of bend curvature. The maximum velocity ratio and velocity offset values could quantitatively characterize the influences of different pipeline layouts on the resistance. The correlation reached 96%. Particle distribution and interparticle forces affected flow resistance. Uniform particle states and weak interparticle forces were conducive to steady transport. Pulse pump pressure led to high flow resistance. It could improve pipe flow stability by increasing flow uniformity and particle motion stability. These results can contribute to safe and efficient paste filling.