| 摘要 |
904,589. Seaming non-metallic sheet material. CARL - ZEISS - STIFTUNG., [trading as JENAER GLASWERK, SCHOTT & GEN.]. Jan. 30, 1961 [Feb. 3, 1960], No. 3496/61. Class 42 (1). [Also in Groups XX and XXIII] In a method for welding synthetic plastic material, the predetermined welding temperature for the appropriate synthetic plastic material to be welded is estimated from the tempering colour of steel members which are in heat contact with the synthetic plastic material during the welding operation. A device for use in carrying out the method consists of a pair of tongs 1 having heat-retaining steel jaws 2. A screw 5 ensures that a predetermined gap remains between the jaws, and the latter can be removable. In the welding process the material is clamped between the jaws 2 and the latter are held over a gas flame until the appropriate tempering colour of steel has spread throughout the jaws. |
