Dilation device for narrow urethra part

The invention provides a urethral stricture part expansion device, which belongs to the technical field of medical machinery, and comprises an outer tube, a water inlet tube, an expandable part and a flow control structure, the water inlet pipe is fixedly connected to the outer wall of the outer pipe; the expandable part is arranged at one end of the outer tube; the expandable part is communicated with the water inlet pipe and is configured to enable fluid to enter the expandable part through the water inlet pipe so as to increase the volume of the expandable part; the flow control structure comprises a limiting structure and an extrusion structure, one end of the limiting structure is fixedly connected with the outer pipe, and the other end of the limiting structure is in contact with the expandable part; the limiting structure is combined with the outer pipe and the expandable part to form a flow control cavity; the extrusion structure is arranged in the flow control cavity; along with the increase of the v