| 摘要 |
<p>A flat metal plate or sheet is rolled into a drum; welded; provided with a flange on each end; and with peripheral ribs i.e. the ribs are formed circumferentially. The metal sheet has a wide tolerance, e.g. of 5-10mm. on its width which forms the length or height of the drum after forming. At the start of the process, the actual sheet width is measured and used to adjust the forming machines so the specified height is obtd. despite the variation in width. Dimension is pref. measured after welding; after forming the end flanges; and possibly after forming the corrugations, but before forming ribs. The size of ribs can then be adjusted so the required height is obtd. The measurements are made without loss of prodn. time in an automatic plant for mfg. the drums.</p> |
