MANUFACTURE OF STRUCTURAL, THERMALLY INSULATING MOLDED PRODUCT AND MOLDED PRODOCT MAXIUFACTURED BY THIS METHOD

摘要

PURPOSE: To obtain heat-insulating structural elements by using foamed thermoplastic material by inserting a pre-molded core inside a high-temperature tubular element made from an extruded thermoplastic, placing the tubular element into a blow-moulding mold, and molding the tubular element onto the pre-molded core. CONSTITUTION: The top such as for laundry washing machine/dishwashing machine 1 comprises an inner core (A) made from a heat-insulating material, for example, foamed impact-resistant polystyrene, and an outer shell (B), made from a compact impact-resistant polystyrene, adhering to the inner core. A tubular element made from the thermoplastic polymer is extruded through an annular slot 7, surrounds the pre-molded core (A), and is kept in its desired position by means of a support 9. An outer shell is formed by blowing air through a duct 8 into the interior of the tubular element, with two half-molds simultaneously closed around the core (A). Since the tubular element is at a higher temperature than the softening temperature of the used polymer, when the mold is closed the outer shell perfectly adheres to the pre-molded core (A), getting sealed around it and forming one single integral structural body.