Abstract: An attachment for a plastic pipe bending machine for automatically and precisely enlarging the end portions of formed plastic pipe for interconnection with other like plastic pipe of same outside diameter.

Abstract: A hydraulic operated machine for expanding lengths of rigid thermo-plastic tubing providing a shiftable table on a base retaining liquid cooling and heating containers movable from a heating to a cooling and a discharge position including means for holding a length of rigid tubing vertically in the heating container. An expansion assembly positioned above the containers adapted to descend into the softened tube in the heating container and forming same by enlargement of the expansion assembly and raising the expanded tube for descent into the cooling container and rigidizing and discharging same following contraction of the expansion assembly.

Abstract: A tube expander apparatus having an axially displaceable central shaft, a plurality of convex expander shoes in succession circumferentially around the shaft, and pivoted linkage arms between the shaft and the expander shoes and including:A. first linkage arms pivoted to the expander shoes and to a fixed support collar which slidably passes the shaft;B. and second and third linkage arms which are pivoted to the expander shoes above and below the latters' axial midpoint and to collars fixed to the shaft.