Transition pipeline with round top and square bottom

The utility model discloses a transition pipeline with a round top and a square bottom, which comprises a pipeline main body (1) and four plane steel plates with the same specification, the four plane steel plates with the same specification are connected to the side surface of the pipeline main body (1) at equal intervals, and each plane steel plate comprises a first parabola-shaped side edge (2), a second parabola-shaped side edge (3) and a bottom edge (4), one end of the first parabola-shaped side edge (2) is connected with one end of the second parabola-shaped side edge (3), the other end of the first parabola-shaped side edge (2) is connected with one end of the bottom edge (4), and the other end of the second parabola-shaped side edge (3) is connected with the other end of the bottom edge (4); the four bottom edges of the four plane steel plates identical in specification are flush with the bottom end of the pipeline body (1), the section of the bottom end of the pipeline body (1) is square, and the sec