| 摘要 |
894,465. Agglutinated fibrous sheet materials. COMPAGNIE DE SAINT-GOBAIN. July 25, 1960 [Aug. 4, 1959], No. 25775/60. Addition to 849,833. Class 140. A process for making mats of glass or other thermoplastic mineral fibres comprising an autogenously-agglomerated mixture of at least two different categories of fibres having the same chemical composition but different thermoplastic properties, the softening temperatures of the categories differing markedly from one another, is characterized in that the mat is pre-heated before agglomeration. As shown, a mat 1 of fibres to be agglomerated is drawn between conveyer belts 2, 3 which are permeable or of open-work structure. Hot air, supplied through hood 4, passes through the mat, is collected in hood 5, thence transferred to hood 6 whence it passes through the mat a second time and is taken up by exhaust hood 7. Further hot air, supplied through hood 8, passes through the mat, is collected in hood 9, thence transferred to hood 10 whence it passes through the mat a second time and is taken up by exhaust hood 11. The mat thus preheated passes into an agglomerating tunnel furnace 12 having electric resistance heating elements 13, 14. The mat is supported on rollers 15. The thickness of the mat diminishes rapidly from its entry into the furnace. On leaving the furnace the mat passes between calender rollers 16, 17, then between containers 18, 19 which cool it and finally between driven rollers 20, 21 which give the mat its movement during its journey through the furnace. |
