Apparatus for screening paper fiber stock

摘要

In screening apparatus for paper making fiber incorporating a cylindrical screen member provided with screening perforations which are either cylindrical or slotted in section, the perforations are characterized by greater flow area on the inlet side of the cylinder than on the accepts side of the cylinder. More specifically, each of the screening perforations includes a generally funnel-shaped portion on the inlet side of the cylinder which leads to a short parallel sided portion on the accepts side of the cylinder.