BLOWN FILM EXTRUSION SYSTEM AND PROCESS FOR MANUFACTURING A PLASTIC PRODUCT

摘要

A blown film extrusion system, comprising a circular die (10) for creating a tube of molten plastic which is blown into a bubble (30). A Cooling stack (1) is provided in the center of the circular die (10), within the bubble (30) in use, the Cooling stack (1) including an integrated IBC exhaust stack (24). Air from within the bubble (30) is drawn into an air inlet manifold (180) and spun to a high velocity into a substantially conical air distributor (150). This causes the air to be forced against the surfaces of the copper tubes (92) causing transfer of heat from the air to the tubes. The air is then expelled at the bottom of the Cooling stack (1) back into the bubble (30), where it rises back up to cool the inner surface of the bubble (30), before being drawn back into the air inlet manifold (180) for re-cooling.

主权项

1. A blown film extrusion system, comprising:
a cooling stack comprised of an integrated IBC Exhaust, an air inlet manifold, a fan assembly and a substantially cylindrical air distributor for receiving a flow of air from said air inlet, said air distributor having spiral vanes and defining an air flow conduit and direction of said air flow, the cooling stack further comprising a substantially cylindrical heat exchanger for receiving said air flow from said air distributor; and means for additional cooling on the inside of the bubble as the tube of molten plastic transitions into a bubble around said cooling stack; the cooling stack being configured to draw air from within said bubble into said heat exchanger via said air distributor, and means for expelling air from said heat exchanger back into the space defined between said bubble and said cooling stack.