| abstract |
Method and apparatus for extruding a structure (10) of a radiant heat exchange panel traversed by a multitude of parallel parallel passages (14, 22, 18 or 34) defined by a multitude of thin wall sections external and internal interconnected and extending longitudinally (16, 18, 20, 24, 30, 26). where the temperature of the plastic material moving longitudinally away from the extrusion outlet (66, 68, 70, 72, 74, 76) is reduced by a fluid (92, 96, 100, 104, 114) flowing in said passages and on their external dimensions, by contact of the external dimensions with pairs of cooled rollers (148, 184), by rolling a liquid medium (153) on the active external side, and by flow of a liquid atomized (240) to obtain a radiation absorbing coating on the outside of the panel structure opposite its active side. Some of the flow fluids are reactive fluids which chemically react with or condense on the hot plastic material to form molecular coatings which enhance the properties of the plastic material as a panel structure. |