Built-in type structure for blocking slurry in process of ejecting pipe out of hole

The utility model provides a built-in type structure for blocking slurry in the process of ejecting a pipe out of a hole. The built-in type structure is characterized in that a connecting steel ring with the U-shaped radial cross section is arranged between the tail portion of a machine head of a pipe ejecting machine and the front end portion of a steel pipe behind the pipe ejecting machine, a left end piece, a bottom piece and a right end piece are sequentially connected and integrally formed to form the connecting steel ring, the tail end of the left end piece and the tail end of the right end piece are welded to the tail portion of an adjacent machine head and the front end portion of the steel pipe respectively, a plurality of bolt holes are formed in the bottom piece in the annular direction of the bottom piece, an annular expansion rubber bar is arranged in a cavity defined by the left end piece, the bottom piece and the right end piece, an annular steel piece is arranged between the expansion rubber b