Abstract: An apparatus for the continuous and nondestructive production of plastic panels which are provided with undercut anchoring studs, web profiles or other forms of attachment (28) on one or both surfaces comprises a temperature-controlled chill roll (11), which has peripheral cooling bores (15) in the roll body (17). The roll body (17) is formed at the circumference as a polygon with flat supporting surfaces (25), against which the molding/demolding strips (13) are placed or from which they are lifted. The molding/demolding strips (13) are moved by means of piston/cylinder arrangements (16) and piston rods (18). The piston rods (18) move through transverse bores through the roll body (17). The melt is filled into molds (27) of the molding/demolding strips (13) by the counterpressure between the shaping roll (11) and a counterroll (10) and is cooled down. During the filling of the molds (27), the molding/demolding strips (13) are pressed against the flat faces of the roll body (17).

Abstract: An apparatus for the continuous and nondestructive production of plastic panels which are provided with undercut anchoring studs, web profiles or other forms of attachments (28) on one or both surfaces comprises a temperature-controlled chill roll (11), which has peripheral cooling bores (15) in the roll body (17). The roll body (17) is formed at the circumference as a polygon with flat supporting surfaces (25), against which the molding/demolding strips (13) are placed or from which they are lifted. The molding/demolding strips (13) are moved by means of piston/cylinder arrangements (16) and piston rods (18). The piston rods (18) move through transverse bores through the roll body (17). The melt is filled into molds (27) of the molding/demolding strips (13) by the counterpressure between the shaping roll (11) and a counterroll (10) and is cooled down. During the filling of the molds (27), the molding/demolding strips (13) are pressed against the flat faces of the roll body (17).

Abstract: An apparatus for the continuous and nondestructive production of plastic panels which are provided with undercut anchoring studs, web profiles or other forms of attachments (28) on one or both surfaces comprises a temperature-controlled chill roll (11), which has peripheral cooling bores (15) in the roll body (17). The roll body (17) is formed at the circumference as a polygon with flat supporting surfaces (25), against which the molding/demolding strips (13) are placed or from which they are lifted. The molding/demolding strips (13) are moved by means of piston/cylinder arrangements (16) and piston rods (18). The piston rods (18) move through transverse bores through the roll body (17).

Abstract: A concrete-protecting panel with integrated undercut protuberances which has an enhanced resistance to groundwater pressure. The protuberances or wing-element pairs (3) of the plastic panel (1) have spread wing elements (3) which may spread open even further in their top region 3.1. The wing elements 3 are connected to one another by a supporting web 4, of which the height is at least 70% of one wing-element pair. The wing-element pairs 2 are fastened on the base plate 5 of the protuberance-containing panel 1 via a foot widened in an arcuate manner.

Abstract: Device for joining of tubular parts (10, 11) made from plastic, especially polyvinylidene fluoride, polypropylene or polyethylene, in which aligned parts (10, 11) exhibiting about the same diameter are pushed together and are welded on abutting surfaces (12, 13) by effect of heat. Abutting surfaces (12, 13) of tubular parts (10, 11) in the direction of the inside pipe space are undercut or recessed so that the edge formed by inside surface (15) of tubular part (10, 11) and the abutting surface springs back opposite the edge formed by outside surface (18) of tubular part (10, 11) and abutting surface (12, 13), and so that parts (10, 11) in the area of abutting surfaces (12, 13) in the axial direction essentially are softened equally deeply, then pushed together and, as a result, are welded together. Especially wherein the heating element (20) consists of a fixed disk (23') and a heating ring (23") of metal with a PTFE-ring (21') which may be additionally fixed.

Abstract: An extrusion and calendering method is provided to produce a plastic panel, in particular for the lining of concrete containers, having strongly undercut anchoring elements. These protrusions preferably include flat-shaped wings which are arranged approximately V-shaped, forming an angle with and being offset in their width from each other. The leading wing upon the manufacturing process has a smaller angle to the normal through the panel base. The wings may also, differing from the rectangular cross sectional shape described, have a round, oval, elliptical or square cross section.