De-watering drum for manufacture of paper, carton or tissue web has regular array of de-watering holes some or all extended in star pattern at the surface into adjacent metal surface

摘要

A paper making de-watering drum has a mantle (13) incorporating a regular array of de-watering holes (11). Some or all of the de-watering holes are extended (21) at the surface into the metal surface. The extensions (21) are grooves which extend radially from the respective hole (11) in radial groups of four to eight or more pref. six grooves. The individual groups are pref. star-shaped. Also claimed is a drum manufacturing process in which the grooves are formed by a stamp or die, followed by de-burring, sand blasting and coating with an anti-wear compound.