| 摘要 |
Method for restoring full web width, in the event of web breaks in a paper-making machine, by threading the paper through the machine, in which method, when a web break 13 has occurred at some location in a paper-making machine, a signal is delivered to a trim shower 6 which can move across the web width and to a fixed shower 7, which showers are thus activated and each deliver a jet of water forming shower tracks in the web, there being formed between these two tracks a "fire-break" 11 of the desired width, intended to prevent continuation of the web break to the leader which is formed by the web strip 16 between one edge of the web and the track from the shower 7, and, immediately after activation of the showers 6 and 7, blow tubes 14 are also activated which give off jets of air which blow that part of the paper web not picked up down underneath the machine in the form of out-throws which are gathered up in the usual way and returned to production, and at the same time a signal is also delivered to a drive unit 5 which, by means of a piston, pushes a guard plate 4 inwards over the wire and the web until it is in level with the shower 7 so that the plate delimits and covers the web strip 16. At the same time, a signal is also delivered to a conventional trim shower 3 which is moved inwards across the wire and web, past the plate 4 and towards a contact device 9 which delivers a signal to the drive unit 5 ordering it to draw the guard plate 4 back to a point outside the wire edge. Thereafter the trim shower 3 is returned and placed in line with the shower 7, whose jet is then shut off. The paper web is then restored to its full width with the aid of the shower 3 which is moved in the direction towards the device 9 at the opposite edge of the web, where the shower may optionally be kept until the next web break occurs. <IMAGE> |
