A method for welding profiled elements in plastic material includes: preparing two profiled elements, arranged with respective weld zones facing one another; making a groove corresponding to at least one weld zone of the profiled elements, the grooving performed by a removal operation on a peripheral edge of at least one profiled element; heating the weld zones; coupling the zones to be welded to one another, pressing the profiled elements together to keep the zones to be welded in reciprocal contact. The coupling step includes: a sub-step of melting the zones to be welded into one another in order to define a welding bead; a sub-step of making a containing compartment defined by the groove, the welding bead being made internally of the containing compartment; and the step of arranging a containing presser in correspondence to the containing compartment for preventing exit of the welding bead from the compartment itself.

A method and a device (10) for welding at least two profiled sections (1) for window or door frames or leaves uses a heating unit (4) introduced between the profiled sections (2, 3) to be joined. At least two heating elements (5, 6) of the heating unit melt the profiled section ends (2, 3) at the end surfaces to be joined. In order to chamfer, in particular remove, a profiled section edge layer (20) of the profiled section ends (2, 3) along the layer surfaces (12, 13) thereof, at least one tool, in particular at least one cutting blade (7, 8), is arranged on the heating elements (5, 6) and is moved such that the material (9) to be melted is displaced into the profiled section interior (11) or into the interior (12) of the profiled section chambers (13). A compression device compresses the profiled section ends (2, 3).

A gasket welding apparatus (10) comprising: a pair of opposed clamping members (16A, 16B) for supporting corresponding first and second lengths of gasket material. The clamping members (16A, 16B) being moveable towards and away from one another by an actuator (58). The gasket welding apparatus (10) comprises a heating element (30), the heating element (30) is moveable between a first position in which it is removed from the clamping members and a second position in which it is disposed between the clamping members.

The machine (1) comprises one welding device (3) for one first profiled element (4) and one second profiled element (5) each provided with at least one area to be welded (6), comprising: first retaining means (8) and second retaining means (9) adapted to retain the profiled elements (4, 5) with the areas to be welded (6) facing each other; one heating plate (17) adapted to heat the areas to be welded (6); one movement assembly (14) for the first retaining means (8) along at least one direction of work (W) parallel to the second profiled element (5); one movement unit (18) adapted to move the heating plate (17) along the direction of work (W);
wherein at least one of either the movement assembly (14) or the movement unit (18) comprises one motorized actuator (21) and wherein the welding device (3) comprises one synchronization mechanism (22) adapted to move the first retaining means (8) at the same time as the heating plate (17) along the direction of work (W).

The machine (1) comprises at least one main welding device (3) of a first profiled element (4) and a second profiled element (5) which extend along their respective longitudinal directions and are each provided with at least one extremal area to be welded (6), the main welding device (3) comprising: main retaining means (18, 19) of the profiled elements (4, 5); main heating means (20) adapted to heat the extremal areas to be welded (6); main displacement means (21) of the main retaining means (18, 19) adapted to displace the profiled elements (4, 5) between a mutual spacing away position and a mutual approaching position;
wherein the main heating means (20) comprise two heating plates (27), each of which can be placed in contact with a respective extremal area to be welded (6) and arranged substantially parallel to each other at a predefined distance to define a free volume (V) positioned between them.