Underground flow self-adaptive adjusting device for well cementation

The utility model provides an underground flow self-adaptive adjusting device for well cementation, which comprises a central pipe, and a first through hole is arranged on the central pipe; a second through hole is formed in the cylinder sleeve; and the adjusting mechanism is arranged in the first annular space between the central pipe and the cylinder sleeve. Wherein the central pipe is configured to be capable of receiving external fluid; the second annular space between the inner cavity of the central pipe and the adjusting device and the shaft is constructed to be capable of forming axial pressure on the adjusting mechanism under the action of external fluid so as to drive the adjusting mechanism to move in the axial direction, and therefore the opening degree of the first through hole and the opening degree of the second through hole are adjusted so that the flow of the fluid flowing into the second annular space can be adjusted. The utility model has the capability of inhibiting the over-high reflux vel