System for hot extruding, drawing, and similarly processing plastomers or elastomers, incorporating a means of recovering and utilizing heated air from the cooling of heated parts

In a system for extruding, molding, drawing and similarly hot processing plastomers or elastomers, utilizing for cylinder heating ventilated electric thermal units mounted on said cylinder, the improvement therein said system is a closed loop type of system comprising a plurality of pipes adapted to deliver hot air from said electric thermal units to areas of said system requiring heat application and to return at least a part of said air to said electric thermal units and wherein said electric thermal units are adapted and constructed to admit hot air into a channel communicating with an insulated hot air storage chamber therefrom a plurality of thermally insulated duct lines extend coupled to specially provided grooves arranged peripherally to the various parts of the blow-working head, or molds, or dies, or flat heads, said hot air being then exhausted through additional duct lines and a three way valve into a drier or dehumidifier acting as a granule feeder, a part of said air being returned to said thermal units to decrease the thermal work of the latter, thereby improving thermal efficiency, said cylinder temperature and pressure working conditions and the life of said thermal units.