A process as claimed for the invention for internal high-pressure reshaping of a hollow section (12) in a reshaping tool, a fluid being introduced under high pressure P₁ into a hollow section and this section having a transitional area with different wall thicknesses in the area of an edge (18 to 21) to be blocked, is characterized in that the shape selected for the hollow section (12) in the initial state is such that a thickened area (22 to 25) extends a certain distance from the edge (18 to 21) into the wall section (14, 16) with smaller wall thickness. As a result, constrictions can be avoided during reshaping and favorable edge geometries can be achieved (FIG. 2).