Blade top steam seal structure

The invention relates to the technical field of through-flow sealing, in particular to a blade top steam seal structure which comprises a stationary blade shroud arranged at the top of a stationary blade, a movable blade shroud arranged at the top of a movable blade and a plurality of steam seal tooth pieces. The stepped structures are arranged at the ends of the movable blade shroud ring and the fixed blade shroud ring, so that the movable blade shroud ring and the fixed blade shroud ring form zigzag geometric channels with the steam seal tooth pieces respectively, when steam enters the geometric channels, airflow is effectively guided to steer and rotate, the airflow collides with follow-up entering airflow under the influence of rotational flow, the kinetic energy of the steam is effectively reduced, and the efficiency of the steam seal is improved. And steam flow sealing steam flow is formed, and the sealing effect is achieved. Meanwhile, steps with different heights are arranged through the step-shaped s