C-shaped wrap twin wire forming machine suitable for use in the methods and the TAD machine to modify a conventional tissue machine to TAD machines

摘要

In a known method of rebuilding a conventional tissue machine having a conventional C-wrap type twin wire forming section to a TAD machine, a TAD section, which includes a looped TAD fabric (24) and at least one TAD cylinder (22) located inside of the TAD fabric loop for thermally predrying the formed paper web (13) by passing hot air through the web, is incorporated in the machine. The rebuilding costs can be reduced, and reduced production costs for the web (13) as well as an increased quality of the produced web can be obtained by substituting a new outer forming fabric (35 or 43) for the existing one (3), said new outer fabric being longer than the existing one and having a comparatively plane web facing surface, so that on separating the two forming fabrics from each other the formed paper web (13) will adhere to and be carried by the web facing surface of the new outer forming fabric (35 or 43), and by providing means (36, 37) for guiding the new outer forming fabric (35 or 43) with its web facing surface into contacting relationship with the TAD fabric (24) upstream of or on the TAD cylinder (22). A new C-wrap type twin wire former, which gives a drier web and is suitable for use in a TAD machine for the manufacture of high basis weight sanitary paper, is disclosed.