Abstract: Procedure for the enlargement of the passage of a pipe (2) in the ground (1), according to which procedure this pipe (2) in the ground (1) is pushed open, characterized in that in the pipe (2) at least one high pressure hose (3) is installed, which, in condition filled by fluid under high pressure, is thicker than the inside of the pipe (2), but in another state without this high pressure, can be brought into the pipe, the high pressure hose (3) is put under pressure with fluid under high pressure until the pipe (2) expands after which the pressure of the fluid (4) in the high pressure hose (3) is lowered.