A procedure for the continuous production of a simple sheet of thermoplastic material provided with one or several tubular sheets comprised between the edges. (Machine-translation by Google Translate, not legally binding)

摘要

A process for the continuous production of a sheet of thermoplastic material provided with one or more tubular sheaths comprised between the edges, intended especially as covering and protective material in general, characterized in that it comprises the phases of extruding a tubular sheet ; confer to said tubular sheet a crush that generates overlapping layers by bending the margins; limiting a zone or several contiguous zones of said tubular sheet comprised along respective pairs of generatrices; operating the welding of said zones on other parts of said sheet in the direction of extrusion, the separation of said areas of the tubular sheet in the form of strips by means of cuts along respective pairs of generatrices, which may take place before or after said welding, the first of said cuts also operating the transformation of the tubular sheet into a single sheet, the separated part of said tubular sheet being integrally used in the formation of said sheaths; and, finally, winding said simple sheet into a reel, preserving the stratified structure by folding the margins caused by said crushing. (Machine-translation by Google Translate, not legally binding)