The time when the cement slurry's column pressure reduces to the water column pressure before or after initial set is directly related to whether or not formation fluids flow out during wait-on-time.
3
其内部由于中心负压而形成空气柱,当流场稳定后,该空气柱从底流口到溢流口贯穿始终。
Air core comes into being because of central minus pressure and goes through the hydrocyclone from the overflow gate to the bottom outlet after the flow field become steady.