| 摘要 |
1349888 Moulding tubes G N BOGRETS G D NIKIFOROV M I OPARIN N M PAVLUSHKIN P D SARKISOV V F DUDKIN and G A ELLERN 21 July 1971 [27 July 1970] 34150/71 Heading B5A [Also in Division C1] Tubes are made from flat thermoplastic strip by passing the strip (4) through the narrowing gap between a mandrel (1) and a circular guide (3), turning out the edges of the strip and joining them by fusing with radiant heat. On the surface of the mandrel may be a wedge shaped projection (2) to bend out the edges of the strip. |
