| 摘要 |
Equipment for welding thermoplastic films has a frame and a heater a lower welding shoe is located immediately beneath an upper one this lower shoe is fixed to the frame or to the upper shoe to form a welding unit which is only supported by the films during welding, thus producing a good weld even with a poor backing material. Suitable for jointing e.g. thick film sheets for covering buildings at site, can be used on any background material such as sand or rough concrete. |
