| 摘要 |
The invention relates to inflatable tubes such as buoyancy tubes for inflatable liferafts and is aimed to provide tubes with bends in them that can be formed with a considerable reduction in the number of cutting and joining operations conventionally required and with a corresponding reduction in numbers of seams and hence sources of leakage. The invention provides a method of making such tube by overlapping and joining the longitudinal edges (231) of a suitable sheet material (230) to make a flattened tube (230A), marking on said tube a fold line (234) corresponding to the desired bend position, marking corresponding areas (237A, 237B) one on each side of the fold line, folding about the fold line to bring and join together these areas and then sealing the ends (232A, 232B) of the tube. By making a number of bends the ends of the tube can be sealed to each other, thereby making an endless tube of polygonal plan form. |
