Apparatus for the formation of an extended nip

摘要

In a papermaking process a paper web (3) passes between a rotating flexible drum (1) and a press shoe (8) nip gap (9) with hydrodynamic lubrication delivered within the gap. The press shoe is mounted on a fixed support and has a number of internal lubricant oil passages (19) terminating in the gap and supplied through a transverse hole (22). The lubricant outlet passages operate incorporate throttle inserts of 0.5 - 2.5 mm diameter which reduced the pressure by pref. 8-12 bar. The lubricant outlet passages are less than 4 mm diameter. The outlets (19) are located at transverse intervals of 15-25 mm and are on the web feed side of the shoe.