METHOD AND WELDING SET FOR HOT-AIR WELDING OF GASKET PROFILE SECTIONS Russian patent published in 2001 - IPC

FIELD: method and welding set for hot-air welding of gasket profile, in particular, for refrigerators, having at least one corrugated air chamber capable of expansion and compression. SUBSTANCE: method consists in arrangement of two profile sections with the ends facing each other, cut above the corner inside the respective device having catches. Then, the ends of both sections are heated up to the softened state, and the catches are joined for mutual connection of the heated end of the pair of sections. After that each of the profile sections gets deadened near the ends, so that the air chambers are completely cut along the deadening sections. Air is injected inside the air chamber by pricking it in the section between the deadening section and the end of each of the profile sections. As a result, pressure is imparted on the walls of the profile sections in this section, pressing them to the walls of the catches. The ends of the pair of profile sections get joined to each other by hot-air welding under pressure. Then, the closed sections are opened and the free end of the pair of welded sections are welded in a similar way to the third section of the profile, then - to the fourth one so as to form a gasket in the form of a frame welded at the corners. The welding set is also described. EFFECT: enhanced strength of welded joints in the zones of welding. 6 cl, 7 dwg