Device for expanding hollow bodies

A method of using a device for expanding a hollow body comprising:

• providing a plurality of sector-shaped expandable jaws disposed in a holder and distributed about a central axis, the expandable jaws extending along the axis to a free end and being radially movable with respect to the axis, each of the expandable jaws including:
• a cylindrical surface having a radius corresponding to a radius of the hollow body in an expanded state of the hollow body and a cutout from the cylindrical surface so as to form an inward radial taper at an area of the free end;
• a plurality of projections and recesses disposed in a joint region between respective ones of the expandable jaws, the projections and recesses being arranged in an alternating manner with each other along the axis and at least partially extending into the area of the free end, the cylindrical surfaces being rounded off so as to transition to respective outer surfaces of the projections and the outer surfaces of the projections extending, at least at ends of the projections, radially inward with respect the cylindrical surfaces, and
• expanding, by the expandable jaws, a pipe end of a plastic pipe having a shape memory.