PROCESS FOR MANUFACTURING A SELF-EXTINGUISHING CABLE

摘要

The invention relates to a process for manufacturing a self-extinguishing cable comprising at least one transmissive element and at least one flame-retardant coating in a position radially external to said at least one transmissive element, wherein said at least one coating includes an expanded flame-retardant polymeric material comprising:(a) at least one expandable polymer; (b) at least one expanding agent; (c) at least one flame-retardant inorganic filler, in an amount of from 100 parts by weight to 250 parts by weight with respect to 100 parts by weight of said at least one expandable polymer; the process comprising the following steps: (i) feeding the flame-retardant polymeric material to an extruding apparatus, therein melting and mixing it; (ii) passing the flame-retardant polymeric material obtained in step (i) through at least one static mixer; (iii) depositing by extrusion the flame-retardant polymeric material obtained in step (ii) onto said at least one transmissive element conveyed to said extruding apparatus. The process of the invention allows to optimise the homogeneity and to maximize the expansion of said flame­retardant polymeric material. The cable so obtained is provided with both good mechanical and flame-retardant properties.