Apparatus for improving heat transfer in drying cylinders of a paper machine and method for assembling the same

In drying cylinder apparatus for use in a drying section of a paper machine, said apparatus including a drying cylinder having a cylindrical mantle defining a hollow interior space bounded by an inner mantle surface and means for increasing the turbulence of a condensate layer formed on said inner mantle surface during operation of the drying cylinder to improve the heat transfer characteristics of the drying cylinder, said means including a plurality of turbulence ribs attached to said inner mantle surface, the improvement comprising:

• a plurality of turbulence ribs attached to said inner mantle surface and extending in a substantially axial direction through said hollow interior space of said mantle;
• means for attaching said plurality of turbulence ribs to said inner mantle surface, said attaching means including a plurality of attachment bands situated in said hollow interior space of said mantle in mutually axially spaced relationship, each band extending substantially circumferentially around said hollow interior space of said mantle adjacent to said inner surface thereof, each attachment band being constituted by an assembly of at least three arcuate-shaped band parts, each band part having a pair of free ends with each free end of one band part being situated adjacent to a respective free end of another band part to form pairs of adjacent free ends, spring means associated with at least one of said pairs of adjacent free ends of said band parts in each attachment band for urging said adjacent free ends away from each other, said spring means exerting a force substantially in the same direction that the free ends move away from each other, means for tensioning said spring means, and means for attaching said turbulence ribs to said attachment bands.