摘要 |
According to the present invention, novel foam panels and blocks are provided which are produced by welding and/or adhering foam tubes to one another. The foam panels are used particularly as insulating and/or drainage panels, and the foam blocks are used for the production of super lightweight panels the cavities of which are optionally filled with gypsum, cement, or other material. Composite structures made therefrom exhibit excellent sound-absorbent properties. Moreover, the invention provides a process and an apparatus for welding foamed synthetic resin tubes to one another and/or to other foam materials. The synthetic resin surfaces to be welded together are guided by way of a spacer means at a distance past an electrically heated heat source to form a heating channel where the surfaces are melted and pressed together thereafter. The process and the apparatus are suited especially well for welding foams of non-crosslinked low-density polyethylenes. |