Device for enlarging pipe ends

Tool for enlarging pipe ends comprising toolholder body means containing axially movable mandrel means having a tapering end and capable of being displaced by an externally applied force, toolhead means exchangeably attachable to the toolholder body means coaxially with the mandrel means and containing a plurality of expanding members in the form of cylinder segment means radially displaceable by the axial displacement of the mandrel means and mounted so that they project axially from the toolhead means, the edge of the segment means facing the mandrel means forming a recess corresponding to the mandrel means taper, adapter means interposed between the toolholder body means and the toolhead means, and having a body containing an axially displaceable supplementary mandrel means having an elongated tapering end for cooperation with the exchangeable toolhead means, the other end of the supplementary mandrel means containing a recess shaped to receive the tapering end of the mandrel means mounted in the toolholder body means said adapter means transferring the motion of the mandrel means of the toolholder body to the expanding members of the exchangeable toolhead means.