Abstract: An assembly for forming a ferrule on a tube, pipe, conduit or the like has a housing, a transverse bore extending through the housing with a medially disposed annular die surface formed therein, the section of the bore facing the annular die surface is threaded to receive a ferrule forming element which can be threaded towards and away from the annular die surface and will form a cavity with the annular die surface for holding lubricant therein when the tube is positioned in the transverse bore so that it extends into the threaded section of the bore, the section of the bore on the side remote from the annular die surface has a plurality of annular channels which form a labyrinth seal with the tube in assembled position in the transverse bore and act to hold the tube and to control the leakage of lubricant therefrom.