PROCEDIMIENTO Y SU CORRESPONDIENTE MAQUINA PARA CALENTAR CON MIRAS A CONTRAERLA UNA ENVUELTA DE MATERIA PLASTICA TERMORRETRACTIL QUE CUBRE UNA CARGA.

摘要

A heat-shrinking plastic envelope round a package is heated by directing hot air on to a ring of the envelope and gradually moving the heated zone over the whole envelope, pref. from the bottom. The hot air is produced immediately adjacent to the heating zone, it flows along the still non-shrunk zones to form preheating areas on the envelope.