EXPANDER HEAD FOR EXPANSION TOOLS AND EXPANDER TOOL EQUIPPED WITH THIS HEAD Russian patent published in 2016 - IPC B29C57/04 B21D41/02 

FIELD: tools.

SUBSTANCE: present invention concerns expander head (1) for expansion tools for hollow billets, in particular for plastic pipe ends and multilayer composite pipes. Head includes a screwed cap (2) equipped with directed radially inside guide flange, and set in the form of sectors of spacer blocks (4). Each block by sector inner flange is arranged with possibility of radial movement in screwed cap (2). Set of sector-shaped spacer blocks (4) moves between closed state and expanding state. In closed state, the envelope of the outer walls of the set of spacer blocks (4) formes approximately cylindrical side surface. Each spacer block (4) has at least one groove (8), propagating in the direction of the longitudinal axis of the spacer blocks (4), so that area of outer walls of the set of spacer blocks (4) in closed state of expander head (1) corresponds to 25 % to 75 % of the area of envelope of the outer walls of the set of spacer blocks. Besides, the present invention relates to expansion tool for hollow billets, which includes the proposed expander head (1).

EFFECT: technical result is reduction of force at expansion of hollow billets.

13 cl, 9 dwg