DISPOSITIVO DE AQUECIMENTO ELECTRICO PARA SISTEMAS DE CANAIS QUENTES E PROCESSO PARA A PRODUCAO DE UM TAL DISPOSITIVO DE AQUECIMENTO

摘要

An electric surface heating element is installed by direct application to the periphery of a cylindrical material pipe (13) of a hot runner nozzle (12). Said surface heating element consists of a ceramic dielectric layer (20) which is directly applied to the metal pipe (13) or to the wall (16) thereof, at least one layer (22) consisting of heating conductor strips (23) and an electrically insulating ceramic covering layer (24) which is applied on top of the latter. Film, or thick-coat screen printing technology are suitable as coating processes. However, thick-coat technology using round printing is preferably used for the layer construction as a whole. Alternatively, the ceramic dielectric layer (20) can be fixed to the periphery of the hot runner pipe (13) in the form of a prefabricated green film and subsequently baked.