| 摘要 |
1,187,136. Seaming non-metallic sheet material. FARBWERKE HOECHST A.G. 13 Nov., 1967 [12 Nov., 1966], No. 51526/67. Heading B5K. [Also in Division F2] Thermoplastic articles, e.g. polyethylene, polypropylene or polyvinyl chloride pipes, are welded by applying extruded thermoplastic filler material 8 on to the seam to be welded, the material 8 having passed through a heated flexible conduit 1 having a heated mouthpiece 4. As shown, the conduit 1 is attached to an electrically heated screw extruder 10 which has a feeding funnel 11 for granular thermoplastic material and is driven by an electric motor 13 through a gear 12. The conduit 1 comprises a polytetrafluoroethylene pipe 2 surrounded by a stainless steel fabric 3 connected through a regulator to a high current generator. The mouthpiece 4 is positioned in a guiding device 5. The region to be seamed is preheated by an electrically heated gas generator 6 or a heated iron and pressure is applied to the material 8 by a roller 7. Control lamps 15, 16, are provided for the various heating circuits. |
