Abstract: Provided is a recycling method of waste polystyrene. In the recycling method, the waste polystyrene is subjected to first swelling and dissolving in water at 140° C. to 300° C. The waste polystyrene may swell and depolymerize in water at 140° C. to 300° C.; meanwhile, the waste polystyrene could self stretch and depolymerize chain segments thereof at 140° C. to 300° C. Under the dual depolymerization mechanism, the polystyrene is remodeled.

Abstract: An assembly of dies for producing W-shaped flanges of a heat-insulating protective component and a method of producing the same by using the assembly of dies. The assembly of dies comprises a terrace-forming die and a bending die. The method comprises only two procedures, namely, stamping a composite base plate into a terraced composite base plate by using a terrace-forming die, and bending and compressing the two terraced sides of the terraced composite base plate by using a bending die so that each of the two terraced sides forms a W-shaped flange.

Abstract: A method of making an S-shaped bent edge component comprising: placing in order an upper layer of metal base plate and a lower layer of metal base plate as well as a middle layer of heat-isolating materials in between; fixing the metal base plates with the heat-isolating materials; forming J-shaped edges on the base plates by stamping, and the J-shaped edges of the base plates are perpendicular to a horizontal portion of the metal base plates; each of the J-shaped edges of the base plates has an outwardly bent curve with a crown and a curve end; by means of a stamping step performed by an upper mold M1 with a concave surface and a flat surface and a lower mold M2 with a flat surface, the concave surface of the mold M1 exerts lateral force onto the curve ends so that the J-shaped edges of the base plates inwardly bend towards the upper metal base plate.

Abstract: The present invention discloses a method for forming hemmed edges at a punch hole of a metal protective component. The manufacturing process is performed by a punch assembly which comprises a pyramidal punch head and a planar surface, a planar die and a die support with disposed with a spring thereunder, wherein the pyramidal punch head of the punch assembly applies downward vertical force towards a center position of the hole, and together with a vertical upward supportive force exerted by the die support, bent edges resembling shape of flower petals are formed at the punch hole; thereafter, as the punch assembly continues to move downwards, the bent edges are bent along a planar gap above the die, and finally the bent edges are pressed to form hemmed edges which are parallel to a base of the component.